Mixed-Humid Climate

Mixed-Humid Climate
September 2005 • NREL/TP-550-38448
Building America Best Practices Series: Volume 4
Builders and Buyers Handbook for Improving New Home Efficiency,
Comfort, and Durability in the Mixed-Humid Climate
NT OF
ME
EN
RT
ER
ED
M
U N IT
ICA
GY
ER
DEP
A
MIXED-HUMID
CLIMATE
ST
A
AT E S OF
U.S. Department of Energy
Energy Efficiency and Renewable Energy
Bringing you a prosperous future where energy is clean, abundant, reliable, and affordable
Building Technologies Program
INTRODUCTION
Taking action in
your community
Building America Best Practices Series: Volume 4
Builders and Buyers Handbook for Improving New Home Efficiency,
Comfort, and Durability in the Mixed-Humid Climate
Prepared by
Pacific Northwest National Laboratory
Michael C. Baechler
Z. Todd Taylor, Rosemarie Bartlett, Theresa Gilbride, Marye Hefty, Heidi Steward
and
Oak Ridge National Laboratory
Pat M. Love
Jennifer A. Palmer
HOMEOWNERS
Shopping for value,
comfort, and quality
MANAGERS
Putting building
science to work for
your bottom line
MARKETERS
Energy efficiency
delivers the value that
customers demand
SITE PLANNERS
& DEVELOPERS
Properly situated houses
pay big dividends
DESIGNERS
Well-crafted designs
capture benefits for builders,
buyers, and business
SITE SUPERVISORS
Tools to help with
project management
TRADES
Professional tips for fast
and easy installation
CASE STUDIES
DISCLAIMER
Bringing it all together
This report was prepared as an account of work sponsored by an agency of the United States Government. Neither the United
States Government nor any agency thereof, nor Battelle Memorial Institute, nor any of their employees, makes any warranty,
express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information,
apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference herein to
any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not necessarily
constitute or imply its endorsement, recommendation, or favoring by the United States Government or any agency thereof, or
Battelle Memorial Institute. The views and opinions of authors expressed herein do not necessarily state or reflect those of the
United States Government or any agency thereof.
Building America Best Practices Series: Volume 4 – Builders and Buyers Handbook for
Improving New Home Efficiency, Comfort, and Durability in the Mixed-Humid Climate
Version 1, 9/2005 • TTL-1
Contents
INTRODUCTION
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . INT-1
Taking action in
your community
Homeowners . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HOM-1
HOMEOWNERS
Quick Tips: Homeowners . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HOM-1
Shopping for value,
comfort, and quality
You’re in Good Company . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HOM-1
How Quality Houses Perform. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HOM-2
MANAGERS
An Energy-Efficient Home Will Cost You Less . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HOM-3
Putting building
science to work for
your bottom line
Energy-Efficient Mortgages Can Help You Get More for Your Money . . . . . . . . . HOM-3
What’s the Score? (HERS). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HOM-4
Guaranteed Energy Costs and Comfort. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HOM-5
MARKETERS
And There’s More - More Green for You and More Green for the Planet . . . . . . . HOM-5
Energy efficiency
delivers the value that
customers demand
What to Look For . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HOM-6
Sources and Additional Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HOM-6
Homebuyer’s Checklist . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HOM-7
Managers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . MNG-1
An Invitation to Building Company Managers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . MNG-1
Building America . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . MNG-1
Quick Tips: Managers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . MNG-1
The Business Case for Building Science and Energy Efficiency . . . . . . . . . . . . . . . . MNG-2
Properly Choosing Materials and Equipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . MNG-2
Reduced Risks, Increased Productivity, and Fewer Callbacks . . . . . . . . . . . . . . . . . . MNG-3
From an Economic Standpoint, Everyone Wins . . . . . . . . . . . . . . . . . . . . . . . . . . . . MNG-3
Customer Satisfaction and Referrals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . MNG-3
Consumers Expect More . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . MNG-4
Competitive Advantage in the Marketplace . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . MNG-4
SITE PLANNERS
& DEVELOPERS
Properly situated houses
pay big dividends
DESIGNERS
Well-crafted designs
capture benefits for builders,
buyers, and business
SITE SUPERVISORS
Tools to help with
project management
TRADES
Professional tips for fast
and easy installation
Take the Next Step . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . MNG-5
Case Studies. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . MNG-5
CASE STUDIES
Sources and Additional Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . MNG-5
Bringing it all together
Marketers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . MKT-1
ENERGY STAR Qualified Homes: Telling Your Story . . . . . . . . . . . . . . . . . . . . . . . MKT-1
Quick Tips: Marketers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . MKT-1
Increase Customer Satisfaction and Let Your Customers Sell Your Product. . . . . . . MKT-2
Sell the Value that Home Buyers Expect . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . MKT-2
How Industry Leaders Sell Energy-Efficient Homes . . . . . . . . . . . . . . . . . . . . . . . . . . MKT-2
Sources and Additional Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . MKT-4
Building America Best Practices Series: Volume 4 – Builders and Buyers Handbook for
Improving New Home Efficiency, Comfort, and Durability in the Mixed-Humid Climate
Version 1, 9/2005 • TOC-1
Contents
Site Planners . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . PLN-1
Lot Orientation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . PLN-1
Quick Tips: Site Planners . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . PLN-1
Shade Trees . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . PLN-3
Other Steps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . PLN-4
Sources and Additional Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . PLN-6
Designers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . DES-1
Quick Tips: Designers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . DES-1
Building Science and the Systems Approach . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . DES-1
The Cost of Doing Business . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . DES-3
Mixed-Humid . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . DES-5
Design Best Practices for Mixed-Humid Climate. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . DES-5
Site - Drainage, Pest Control, and Landscaping . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . DES-5
Foundation Measures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . DES-7
Structural Moisture Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . DES-10
Structural Air Sealing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . DES-14
Structural Thermal Performance. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . DES-16
Heating, Ventilating, and Air Conditioning (HVAC). . . . . . . . . . . . . . . . . . . . . . . . DES-25
Mechanicals Management and Appliances . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . DES-33
Sources and Additional Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . DES-35
Site Supervisors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . SUP-1
Managing Expectations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . SUP-1
Develop a Work Plan . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . SUP-2
Plans - Get Them Right . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . SUP-2
Plans - Keep Them Right. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . SUP-2
Contracts - Write Them Down . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . SUP-3
Pre-Construction Meeting - Have One . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . SUP-4
Permits - Grease the Skids . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . SUP-4
Managing Execution. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . SUP-5
Training . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . SUP-5
Scheduling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . SUP-6
Quality Assurance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . SUP-7
Spot-Check Inspection Checklist . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . SUP-8
Pre-Drywall Inspection Checklist . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . SUP-9
Pre-Occupancy Inspection Checklist . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . SUP-10
Sources and Additional Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . SUP-11
Building America Best Practices Series: Volume 4 – Builders and Buyers Handbook for
Improving New Home Efficiency, Comfort, and Durability in the Mixed-Humid Climate
Version 1, 9/2005 • TOC-2
Contents
Trades . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . TRD-1
Slab Insulation - Cold Climates . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . TRD-2
Basement & Conditioned (Unvented) Crawlspace Insulation . . . . . . . . . . . . . . . . . . TRD-4
Housewrap. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . TRD-6
Window Flashing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . TRD-7
Air Sealing - Plumbing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . TRD-9
Electrical Air Sealing. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . TRD-10
Air Sealing Drywall. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . TRD-11
Air Sealing Glossary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . TRD-12
Fiberglass Insulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . TRD-13
Masonry Construction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . TRD-14
Radiant Barriers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . TRD-15
Duct Sealing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . TRD-16
Case Study: Ideal Homes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . CASE A-1
Case Study: Melrose Commons II . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . CASE B-1
Case Study: John Wieland Homes & Neighborhoods, Inc. . . . . . . . . CASE C-1
Appendix I: Homebuyer’s Checklist . . . . . . . . . . . . . . . . . . . . . . . . . . . . APPENDIX I-1
Appendix II: Energy & Housing Glossary. . . . . . . . . . . . . . . . . . . . . . APPENDIX II-1
Appendix III: Code Notes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . APPENDIX III-1
Appendix IV: Counties in the Mixed-Humid Climate . . . . . . . . . APPENDIX IV-1
Appendix V: Web Site References . . . . . . . . . . . . . . . . . . . . . . . . . . . . APPENDIX V-1
Building America Best Practices Series: Volume 4 – Builders and Buyers Handbook for
Improving New Home Efficiency, Comfort, and Durability in the Mixed-Humid Climate
Version 1, 9/2005 • TOC-3
Acknowledgments
The U.S. Department of Energy’s (DOE) Building America program is comprised of public/
private partnerships that conduct systems research to improve overall housing performance,
increase housing durability and comfort, reduce energy use, and increase energy security
for America’s homeowners. Program activities focus on finding solutions for both new
and existing homes, as well as integrating clean onsite energy systems that will allow the
homebuilding industry to provide homes that produce more energy than they use. In addition
to the DOE management and staff, the Building America Program includes seven consortia,
four national laboratories, and hundreds of builders, manufacturers, and service providers.
Building America works closely with the Department of Housing and Urban Development’s
(HUD) Partnership for Advancing Technology in Housing (PATH) Program, co-manages the
ENERGY STAR Program along with the Environmental Protection Agency, and works with
other federal agencies to coordinate research findings and disseminate information. These
partners make the program a successful source of knowledge and innovation for industry
practitioners and government policy makers. Together, these cooperating agencies have
provided reviews and shared insightful comments, as well as making the authors aware of
their technical libraries.
The U.S. DOE Building America Program funded the development of this series of
handbooks. DOE also funded the Building America consortia and national laboratories to
form the basis for these best practices. The seven consortia are listed on the back cover of
this document. The consortia have taken on the hard work of applied research, field testing,
training builders, and transforming the results into building practices. Numerous drawings,
descriptions, photos, and case studies originated with the consortia.
INTRODUCTION
Taking action in
your community
HOMEOWNERS
Shopping for value,
comfort, and quality
MANAGERS
Putting building
science to work for
your bottom line
MARKETERS
Energy efficiency
delivers the value that
customers demand
SITE PLANNERS
& DEVELOPERS
Properly situated houses
pay big dividends
Many builders have chosen to use the Building America process in collaboration with the
consortia and are quoted in this series of best practices with over a dozen featured in case
studies. These builders deserve thankful recognition for contributing to the success of the
Building America Program and the Best Practices Series.
DESIGNERS
Building America partners worked diligently on this project to further the cause of efficiency,
resource conservation, or improved building performance. These groups have voluntarily
supplied technical materials, review comments, or help in distribution. These contributors
include Southface Energy Institute; Energy and Environmental Building Association,
Wisconsin ENERGY STAR Homes Program; Consortium for Energy Efficiency, Air
Conditioning Contractors of America, National Fenestration Rating Council, and National
Association of Home Builders. National Association of State Universities and Land Grant
Colleges Extension Service Professors from universities throughout the nation provided
valuable and in depth contributions. In particular, professors from the following universities
devoted their time and shared their insights: University of Kentucky, Cornell University,
University of Florida, University of Louisiana; and the University of Minnesota.
SITE SUPERVISORS
Well-crafted designs
capture benefits for builders,
buyers, and business
Tools to help with
project management
TRADES
Professional tips for fast
and easy installation
CASE STUDIES
Bringing it all together
This project required coordination among the national laboratories. Pacific Northwest
National Laboratory and Oak Ridge National Laboratory have taken the lead at producing
this document. The National Renewable Energy Laboratory made its library of Building
America documents available to the authors, reviewed the document, and has responsibility
for posting the document to the Web. Scientists at Lawrence Berkeley National Laboratory
reviewed the document contents.
Christina Van Vleck lent this project her skill as a graphic artist. She prepared all of the
original drawings and designed and laid out the overall series of books.
The authors and DOE offer their gratitude to the many contributors that made this
project a success.
Building America Best Practices Series: Volume 4 – Builders and Buyers Handbook for
Improving New Home Efficiency, Comfort, and Durability in the Mixed-Humid Climate
Version 1, 9/2005 • ACK-1
Welcome
Taking action in your community
INTRODUCTION
This best practices guide is part of a series produced by Building America. The guide
book is a resource to help builders large and small build high-quality, energy-efficient
homes that achieve 30% energy savings in space conditioning and water heating in
the mixed-humid climate. The savings are in comparison with the 1993 Model Energy
Code. The guide contains chapters for every member of the builder’s team—from
the manager to the site planner to the designers, site supervisors, the trades, and
marketers. There is also a chapter for homeowners on how to use the book to provide
help in selecting a new home or builder.
•
•
•
•
Homeowners will find how energy-efficient homes package value, comfort, economy,
durability, and performance. This chapter is a great introduction to energy-efficient
home technologies and provides helpful checklists of what to look for when
home shopping.
Managers will learn why building energy-efficient homes makes business sense. They will
find out how much consumers value energy efficiency and the quality that comes with it,
and how their company can gain market advantage by building energy-efficient homes.
Marketers will learn about great resources for selling energy-efficient homes, including
getting plugged into the ENERGY STAR® nationally recognized branding program.
Site Planners will discover the huge impact building orientation, landscaping, and shading
can have on energy costs, plus learn tips on moisture management and pest control.
• Designers will learn about the systems approach to home design backed up by
building science. They will get guidance on key building components for designing
energy-efficient homes.
• Site Supervisors will get guidance on contract specifications, tips on scheduling and
training, and handy checklists for quality assurance and commissioning inspections.
• Trades will find step-by-step, easy-to-follow illustrated instructions for adding key
energy efficiency technologies.
The last chapter has case studies showing real-life examples of builders who are designing
and constructing energy-efficient houses in the mixed-humid climate zone.
We designed this guidebook to be taken apart, passed around, and updated. Give
the sections of the book to the right people in your organization. Pass on pieces to
subcontractors to help them understand your objectives. Copy it as needed.
Taking action in
your community
HOMEOWNERS
Shopping for value,
comfort, and quality
MANAGERS
Putting building
science to work for
your bottom line
MARKETERS
Energy efficiency
delivers the value that
customers demand
SITE PLANNERS
& DEVELOPERS
Properly situated houses
pay big dividends
DESIGNERS
Well-crafted designs
capture benefits for builders,
buyers, and business
SITE SUPERVISORS
Tools to help with
project management
TRADES
Professional tips for fast
and easy installation
CASE STUDIES
Bringing it all together
This first series of guides helps builders understand and implement the Building
America process to reach 30% energy savings in space heating and cooling and water
heating. Future guides will aim at even higher levels of efficiency based on the latest
Building America research, giving builders the knowledge they need to build even
more efficient and durable houses.
The practices in this book are intended for the mixed-humid climate zone. Visit
www.buildingamerica.gov for information on handbooks covering other climate regions.
Building America Best Practices Series: Volume 4 – Builders and Buyers Handbook for
Improving New Home Efficiency, Comfort, and Durability in the Mixed-Humid Climate
Version 1, 9/2005 • INT-1
Introduction
Mixed-Humid Climate
The mixed humid climate stretches from the Mid Atlantic states west to Oklahoma and Kansas. Housing is
diverse across this wide swath of the Nation’s mid section. Slabs, crawlspace, and basement foundation systems are
all popular. Houses in this climate face a heating season of up to 4500 heating degree days and average outdoor
temperatures dropping below 45°Farienheit in winter. The summer cooling season is often blistering hot and
humid. And many areas have moderate to high rainfall.
Designers and builders face the challenge of controlling the infiltration of moisture-laden air into the building
envelope and keeping moisture away from cold surfaces where condensation may degrade structural materials
and contribute to mold growth. Wall and roof assemblies must accommodate moisture transfer in two directions.
Controlling solar gain is a major challenge.
BUILDING AMERICA CLIMATE REGIONS
The top map shows the Building America designated climates
for most of the country. The bottom map highlights just the
mixed-humid climate.
MIXED-HUMID
MIXED-HUMID CLIMATE
CLIMATE
Building America Process
Many builders choose to try out Building America ideas in a
prototype house. After building one or a few prototypes they
decide what features they will carry forward into their regular
construction. This chart shows a process for working with a
Home Energy Rating System (HERS) rating professional, an
engineer, or an architect to build this first house and on an
ongoing basis. The person offering guidance could also be a
company designer who has become familiar with this document
or has taken other Building America training. An educated staff
will be the best means of selecting building science support.
Building America Best Practices Series: Volume 4 – Builders and Buyers Handbook for
Improving New Home Efficiency, Comfort, and Durability in the Mixed-Humid Climate
Version 1, 9/2005 • INT-2
Introduction
BUILDING SCIENTIST
BUILDER
ENGINEER / ARCHITECT / HERS RATER
PHASE #1
Management decides to go
forward with best practices
and company submits plan
to building scientist
Management tracks
financial benefits
Designer evaluates changes
in style and materials
Decision
PHASE #2
Pre-Construction
Analysis
Offers design solutions based
on whole building analysis,
including materials compatibility
and durability, and system
tradeoff modeling
Determines impact of design
solutions, including energy savings
Site Supervisors evaluate skills,
subcontractors and code issues
Management ensures proper
materials are purchased
and available
Educates builders about building
science and systems approach
PHASE #3
Construction
Communicates design approach
to supervisors and crew
Observes construction practices
and recommends improvements
and offers training
Site Supervisors train crews
and set clear expectations
Trades professionals implement best practices
in their installation and construction processes
Company evaluates success
and decides on next steps
Company creates marketing
program to emphasize
improvements
Site Planners integrate lessons
learned in selection and siting
of future communities
PHASE #4
Post-Construction
Evaluation
PHASE #5
Marketing
PHASE #6
Lessons Learned
Conducts field tests and
inspections including blower
door, duct pressure, and HVAC
system tests
Provides test results and
data for marketing
Offers help with upgrading
production plans and with solar
and green community design
Designer adds new features to
production plans
*Icons correspond with chapters and company capabilities
Building America welcomes reader feedback on this second volume of the Best Practices Series. Please submit your
comments via e-mail to: Michael Baechler ([email protected]) or Pat Love ([email protected]). You can
learn more about Building America and download additional copies of this document at www.buildingamerica.gov.
Building America Best Practices Series: Volume 4 – Builders and Buyers Handbook for
Improving New Home Efficiency, Comfort, and Durability in the Mixed-Humid Climate
Version 1, 9/2005 • INT-3
Homeowners
Shopping for value, comfort, and quality
INTRODUCTION
Comfort. Economy. Durability. Performance. Some homes force you to choose.
Energy-efficient homes deliver it all. And as a homebuyer, you deserve, and should
demand, the whole package.
One way to know you have found an energy-efficient home is to look for the
ENERGY STAR® label. ENERGY STAR has taken much of the guesswork out of
buying new homes and other products. ENERGY STAR-qualified new homes are
built to strict energy-efficiency guidelines using proven technologies and construction
practices. Your builder also may have incorporated other building features that go
beyond ENERGY STAR criteria for even more energy savings, and for greater
health and comfort.
ENERGY STAR features should be included in all houses from lower cost starters
to high-end customs. This chapter gives you an introduction to the technology that
makes these houses work, how much they cost, how to pay for them, and a checklist
of what to look for in new homes. The features described here are specifically designed
for the mixed-humid climate found in the United States.
The companies that build ENERGY STAR homes are among the best and largest in
the nation. Over 2,000 builders work with ENERGY STAR in the United States.
And about 50% of the largest 100 builders in the nation have at least one division
building ENERGY STAR
qualified homes. Thousands
of small companies also build
QUICK TIPS | HOMEOWNERS
ENERGY STAR homes. And
many of these companies are
• Look for the ENERGY STAR label
working with Building America.
for government-endorsed proof that
a home is energy efficient.
In addition to discussing the
• Use the enclosed checklist to shop
for energy-efficient homes.
• Use the nationally recognized HERS
rating to know just how efficient the
homes you are considering really are.
• Own a home you can be proud of
—energy-efficient homes are good
for the environment.
HOMEOWNERS
Shopping for value,
comfort, and quality
MANAGERS
Putting building
science to work for
your bottom line
MARKETERS
Energy efficiency
delivers the value that
customers demand
SITE PLANNERS
& DEVELOPERS
Properly situated houses
pay big dividends
You’re in Good Company
• Learn why an energy-efficient home
is usually a higher quality home all
the way around.
Taking action in
your community
minimum requirements for
attaining ENERGY STAR,
this packet suggests other
techniques developed within the
U.S. Department of Energy’s
Building America program. These
techniques can help you avoid
common construction problems
that occur in the mixed-humid
climate. The recommendations
in this chapter are based on
Building America’s building
science research on over 25,000
homes in 34 states encompassing
every climate region in the nation.
Building America works with
Building America Best Practices Series: Volume 4 – Builders and Buyers Handbook for
Improving New Home Efficiency, Comfort, and Durability in the Mixed-Humid Climate
DESIGNERS
Well-crafted designs
capture benefits for builders,
buyers, and business
SITE SUPERVISORS
Tools to help with
project management
TRADES
Professional tips for fast
and easy installation
CASE STUDIES
Bringing it all together
Version 1, 9/2005 • HOM-1
Homeowners
the nation’s premier building scientists to conduct research and share knowledge with
builders to help build better homes.
If you are looking for energy-saving features in your new home you’re in good
company. Recent homebuyer surveys have found that energy efficiency is the top
upgrade that homebuyers choose in new homes (Johnston 2000). And homebuyers in
Phoenix rated energy efficiency as the number one reason related to the house itself in
determining their satisfaction with the production builder recognized by Professional
Builder magazine as having the top customer satisfaction in the nation (2003). This
same builder won the J.D. Powers and Associates top ranking for customer satisfaction
in 12 of 21 markets in the United States. The winner, Pulte Homes, is a Building
America Partner that brands its homes using ENERGY STAR.
Mixed-Humid Design Features
A. Efficient Windows: help to control
and reduce ultraviolet light that can fade
carpets and furniture, helping to keep
your belongings looking like new and
keeping window areas cooler and more
comfortable to sit near. Window flashing
protects against water leaks.
B. Compact and Tightly Sealed Duct
Runs: shorter runs mean less to go
wrong and fewer air leaks to put air
where it is intended to go, with fewer
contaminants like humidity and dust from
attics or crawlspaces. Leaky ducts are
a major contributor to mold problems.
Return air paths ensure balanced
air pressure for less drafts and more
balanced temperatures throughout the
house. Put ducts in conditioned space,
if possible.
How Quality Houses Perform
You don’t want to spend the first several months in your new home fixing construction
problems. Not long after unlocking a new home’s door for the first time comes the
reality of keeping the house and its inhabitants happy and comfortable. You’ll save
time, money, and personal energy when you buy a house that works from the start.
The building materials and quality that go into an energy-efficient home help to keep
temperatures even, the air clean, and the house dry, quiet, and draft-free. In a welldesigned home, systems are designed to work together for optimal performance. The
checklist near the end of this chapter provides details of what to look for in quality
home construction. Figure 1 provides an overview of features Building America
recommends to help you avoid problems, while saving time, money, and energy.
C.
than bigger equipment, saves energy,
and is designed to comfortably handle
heating and cooling loads.
D. Ventilation: exhaust fans remove
moisture and pollutants. A controlled,
filtered air intake ensures plenty of
fresh air. A fresh air intake is not an
ENERGY STAR* requirement but it is
recommended.
E.
Dehumidifier: sometimes needed to
control indoor humidity, may be needed
for basements.
FIGURE 1: Mixed-Humid Design Features
All of these features save energy. Read the descriptions at right to see what else they do.
Right-Sized and High-Efficiency
HVAC Equipment: costs less to install
F.
Sealed Combustion Appliances:
reduce moisture buildup and ensure
the removal of combustion gases.
We recommend against non-vented
combustion appliances such as nonvented fireplaces or heaters.
G. Overhangs: provide shade and direct
water away from the house. Overhangs
are not required by ENERGY STAR but
are a sign of thoughtful design.
H. Insulation: holds comfortable
temperatures in conditioned spaces and
helps control noise. For insulation level
recommendations visit www.ornl.gov/sci/
roofs+walls/insulation/ins_16.html
I.
Air Sealing: stops drafts, helps keep humid
ity and garage contaminants out of the house,
and creates a barrier to rodents and insects.
J.
Well-Designed Moisture Barriers
and Drainage: avoid expensive
structural damage and help stop
humidity, mold, and mildew.
K.
* ENERGY STAR requirements are changing and an Indoor
Air Quality option is available that includes ventilation.
Building America Best Practices Series: Volume 4 – Builders and Buyers Handbook for
Improving New Home Efficiency, Comfort, and Durability in the Mixed-Humid Climate
Building System: Perhaps the best
thing about buying a system-designed
house is that all of the parts are designed
to work together. This can save you
money on the purchase price, and it also
means a durable and comfortable system,
one that will help avoid maintenance and
repair costs down the road.
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Homeowners
An Energy-Efficient Home Will Cost You Less
As with any upgrade, precisely how much is paid for an energy-efficiency upgrade will
depend on many factors. Some builders make energy-efficiency features part of their
base price, meaning the cost is built into the overall cost of the house. Others will sell
you a specific upgrade package at a predetermined cost. Depending on how the builder
structures his costs, the home’s size and design, and the prevailing cost of building
materials, the additional cost of a system-designed energy-efficient home may range
from zero to $1,500 or more.
But even if you pay more up front, the good news is you are likely to pay less for an
energy-effiicient house on a monthly basis, if you consider the cost of energy. Here’s
an example showing why:
“You don’t know the quality
of life you can experience
until you’re in one of these
homes. Our quality of life has
improved tremendously and
we’ll realize energy cost savings
for years to come.”
John Russo, purchased an ENERGY
STAR home in 2002, as quoted in the
Boston Herald, December 6, 2002.
FIGURE 2: Monthly Cost Comparison
TOTAL MONTHLY = $1,334
TOTAL MONTHLY = $1,303
$175
< ENERGY BILLS >
$135
$31
MONTH
SAVINGS
$372
YEAR
$1,159
STANDARD HOME
< MORTGAGE BILLS >
$1,168
ENERGY STAR® HOME
According to the U.S.
Environmental Protection
Agency, which manages the
ENERGY STAR program with
the U.S. Department of Energy,
100,000 new homes have now
earned the ENERGY STAR
designation, saving these
homeowners a total of $26 million
in energy costs every year.
Our example assumes a base price on the house of $200,000, an upgrade cost of
$1,500, and a 30-year mortgage at 6% interest. We also estimate that monthly energy
bills will be about $135 after energy savings of about $40 per month in the energyefficient home.
Your builder, realtor, or lender should be able to help you work through the savings for
your house based on actual features, costs, and interest rates.
Energy-Efficient Mortgages Can Help You Get More for your Money
Lenders recognize that owning an energy-efficient home makes financial sense and
they have developed energy-efficient mortgages to encourage consumers to purchase
these types of homes. The loans work by allowing consumers to borrow more than they
would typically qualify for.
“If you can save $1,000 a year
on heating bills – to someone
who is making a $1million a
year, this doesn’t mean much.
But to someone who is making
$30,000 to $40,000, this is a
big piece of change.”
Les Bluestone, owner of Blue Sea
Development Company in New York
The following features for energy-efficient loans are taken from Fannie Mae, the
nation’s largest source of funding for mortgages. You can learn more about Fannie Mae
at www.fanniemae.com.
Building America Best Practices Series: Volume 4 – Builders and Buyers Handbook for
Improving New Home Efficiency, Comfort, and Durability in the Mixed-Humid Climate
Version 1, 9/2005 • HOM-3
Homeowners
• Energy-efficient mortgages (EEM) are available for both purchase and
refinance in conjunction with most Fannie Mae first mortgage products,
including conventional fixed-rate and adjustable-rate mortgages.
• Monthly savings resulting from energy efficiency can be used to qualify
borrowers for a larger mortgage. This means consumers can buy more home
in the form of energy efficiency or other upgrades.
• The EEM can be used with many Fannie Mae mortgage products. The
guidelines of the selected Fannie Mae mortgage apply, with the EEM allowing
for the projected energy savings to provide an adjustment to the loan-to-value
and qualifying ratios that favor the borrower.
• To qualify, you must obtain a Home Energy Rating System (HERS) report,
which provides a rating of the energy efficiency of the home and estimates the
resulting cost savings using average utility rates and usage data. See What’s the
Score? below for more information on HERS. Building America recommends
that every home receive this type of rating and many ENERGY STAR homes
were rated in order to qualify.
FIGURE 3: HERS Score
*
“We wanted to prove that you
could do it [energy efficiency]
with a house of this magnitude.
It was a thrill to see just how
much energy efficiency was
possible.”
Michelle Horstemeyer, the lead
builder from John Wieland Homes
who teamed with Building America
to achieve 50% energy savings
and a HERS score of 91.1 on the
sprawling, 6,431-sq. ft., $1.3 million
New American Home in Atlanta,
Georgia.
Based on 2004 International Energy Conservation Code
(*ENERGY STAR standards are under revision and are scheduled to change in 2006)
What’s the Score?
The Home Energy Rating System (HERS) is a nationally recognized method of
evaluating a home’s energy performance. Rating professionals are people trained
in preparing HERS scores and accredited by the Residential Energy Services
Network, found on the Web at www.natresnet.org.
HERS scores can be used to compare across houses even if the houses differ in
design, size, or type of HVAC equipment. Even if homes are not participating in
labeling programs like ENERGY STAR, the HERS score can be used to gauge
energy efficiency. See the Designers
section for more information on HERS.
Building America Best Practices Series: Volume 4 – Builders and Buyers Handbook for
Improving New Home Efficiency, Comfort, and Durability in the Mixed-Humid Climate
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Homeowners
Consumers using Federal Housing Administration (FHA) loan insurance should
consider FHA’s Energy Mortgage Program. This program helps borrowers to
include energy-efficiency features in their home by stretching the size of the
loan they may qualify for without increasing their down payment. An energyefficient mortgage is one of many FHA programs that insure mortgage loans. FHA
encourages lenders to make mortgage credit available to borrowers who would not
otherwise qualify for conventional loans on affordable terms (such as first-time
homebuyers) and to residents of disadvantaged neighborhoods (where mortgages
may be hard to get). To learn more about FHA programs visit the Web site at
www.hud.gov/offices/hsg/sfh/eem/energy-r.cfm.
Some builders are working with lenders to offer special mortgage terms, such as a lower
interest rate, to help buyers of energy-efficient homes. Ask your builder if they have any
special programs.
Guaranteed Energy Costs and Comfort
Some builders go even further than doing a great job of constructing an energyefficient home. Some guarantee it. Builders who guarantee their homes are willing to
tell buyers how much energy the home should use, and they guarantee these levels will
not be exceeded. These guarantees are backed up with payments if limits are exceeded.
Builders can work with insulation companies or other partners to offer guarantees or
caps on their home’s energy costs, or they may develop their own programs. Some
cover room comfort by guaranteeing that the temperature at the thermostat will not
vary by more than 3 degrees at the center of any room served by that thermostat. A
Building America team helped to develop these programs. Information on three of
these programs can be found at:
• Environments for Living – www.eflhome.com/index.jsp
Building America helped
Veridian Homes of Wisconsin
to design a prototype home
packed with innovative features
and designed as a system.
“We actually incorporated all
those ideas into every house
that we build. That is now our
standard,” said Jeff Simon,
Veridian’s executive vice
president of operations.
• Engineered for Life – www.us-gf.com/engineered.asp
• The Energy Use and Comfort Guarantee –
www.artistichomessw.com/guarantee.htm
And There’s More – More Green for You and More Green for the Planet
Where else can you find an investment that delivers monthly dividends, makes
you more comfortable and your house more durable, comes with its own financing
incentives, and may even have guaranteed energy performance? ENERGY STAR
homes give you all this, plus they are good for the environment. Just one ENERGY
STAR qualified new home can keep 4,500 pounds of greenhouse gases out of our
air each year.
Just one ENERGY STAR
qualified new home can keep
4,500 pounds of greenhouse
gases out of our air each year.
Last year, thanks to programs like ENERGY STAR and other energy efficiency
measures, Americans cut their energy bills by more than $7 billion, along with saving
enough energy to power 15 million homes. The greenhouse gas emissions saved by
these steps was the equivalent of taking 14 million cars off our country’s roads. Visit the
ENERGY STAR Web site at www.energystar.gov to learn more about how ENERGY
STAR is helping the environment.
Building America Best Practices Series: Volume 4 – Builders and Buyers Handbook for
Improving New Home Efficiency, Comfort, and Durability in the Mixed-Humid Climate
Version 1, 9/2005 • HOM-5
Homeowners
What to Look For
Take the Homebuyer’s Checklist at the end of this chapter with you when you’re
shopping for a new home. Ask your builder or salesperson to help you consider each
item. For a more detailed checklist, go to Appendix I. You may want to ask to see
houses under construction to see how some measures are installed. The builder or
realtor may have models and displays to help you see other features and ask to see the
home’s owners manual. Not all of the measures will apply to every home (for example,
homes don’t typically have more than one kind of heating system). Check the features
that are most important to you. We’ve left some blank spaces at the end of the checklist
in Appendix I so you can fill in features that you want to remember to check that may
or may not be energy related.
You can learn more
about Building America
and download additional
copies of this document at
www.buildingamerica.gov
If You’re Building a Custom Home
A great advantage to building a custom home, or ordering your home before it is built,
is that you can work with your builder or designer to get the features you want. Give
your builder or designer this Best Practices Guide. It contains everything they need to
design and build a durable and comfortable energy-efficient home.
Sources & Additional Information
• J.D. Power and Associates. J.D. Power and Associates 2004 New Home
Customer Satisfaction Study. West Lake Village, California. 2004.
• Johnston, David. 2000. “Buyer Green.” Professional Builder, September 2000.
www.housingzone.com
• Professional Builder. “Customer Service Standard Setters.” September 2003.
www.housingzone.com
Web Sites Not Included with Published Documents Above
• www.artistichomessw.com/guarantee.htm
• www.buildingamerica.gov
• www.buildiq.com
• www.energystar.gov
• www.housingzone.com/topics/pb/green/survey/buyer.asp#
• www.hud.gov/offices/hsg/sfh/eem/energy-r.cfm
• www.eere.energy.gov/consumerinfo/energy_savers/?appliances.html
• www.eflhome.com/index.jsp
• www.fanniemae.com
• www.natresnet.org
• www.ornl.gov/sci/roofs+walls/insulation/ins_16.html
• www.us-gf.com/engineered.asp
Building America Best Practices Series: Volume 4 – Builders and Buyers Handbook for
Improving New Home Efficiency, Comfort, and Durability in the Mixed-Humid Climate
Version 1, 9/2005 • HOM-6
Homeowners
Homebuyer’s Checklist for Mixed-Humid Climate
Use the following checklist to compare house features in different homes you visit.
A more detailed checklist is available in Appendix I.
MEASURE
Building
America
Builder Builder Builder
#1
#2
#3
BUILDER SERVICES AND RATINGS
ENERGY STAR Rated
Yes
HERS Score of 86 or greater
Yes
Energy Performance Guarantee
Good Idea
Energy Efficient Mortgage
Good Idea
Provides Owners Manual
Yes
If you can answer yes to the above questions you will have a good energy performing home.
Note that in some states, due to more aggressive energy codes, ENERGY STAR may require
HERS scores greater than 86.
VENTILATION
Controlled fresh air provided in the house
Yes
Quiet Exhaust vents in bathrooms
Yes
Quiet Exhaust (not recirculating)
vents in the kitchen
Yes
Supply and return air vents or paths
in bedrooms
Yes
WINDOWS
Windows flashed to help repel water
Yes
Windows rated 0.35 U-factor
and 0.35 SHGC*
Yes
*Solar Heat Gain Coefficient
COMBUSTION APPLIANCES
Combustion appliance exhausts vented
to the outside (except ovens)
Yes
Hardwired carbon monoxide monitors
included for every 1000 square feet of
living space if combustion appliances
or an attached garage are present
Yes
DEHUMIDIFIER
ENERGY STAR Dehumidifier may be
needed in conditioned basements or
other spaces
As Needed
MORE TO LOOK FOR TO ENHANCE ENERGY EFFICIENCY
ENERGY STAR qualified light fixtures
Good Idea
ENERGY STAR qualified refrigerator
Good Idea
ENERGY STAR qualified dishwasher
Good Idea
ENERGY STAR qualified clothes washer
Good Idea
Building America Best Practices Series: Volume 4 – Builders and Buyers Handbook for
Improving New Home Efficiency, Comfort, and Durability in the Mixed-Humid Climate
Version 1, 9/2005 • HOM-7
Managers
Putting building science to work for your bottom line
INTRODUCTION
Taking action in
your community
This document tells company leaders how to use proven technologies and a successful
marketing program to gain competitive market advantage and improve your
company’s economic and product performance. A more efficient home can mean
a faster return on your investment
HOMEOWNERS
Shopping for value,
comfort, and quality
MANAGERS
An Invitation to Building
Company Managers
We invite you to use the information
in this packet to lead your company to
increased profits and greater customer
satisfaction. Building America is a
U.S. Department of Energy (DOE)
program that has sponsored building
science research on 25,000 homes
nationwide. These technologies and the
Building America systems approach can
set your company apart, giving you a
considerable competitive advantage in
how you design, build, and sell homes.
Putting building
science to work for
your bottom line
“The level of training and knowledge that
Building America has exposed us to is
invaluable. The houses we put out today
are just a lot better product…”
Vernon McKown of Ideal Homes in Oklahoma.
According to McKown, Ideal is able to meet
Building America standards and still earn
32% profit margins because they look at the
whole house as a system and choose which
improvements make the most sense.
Building America
Building America works with the nation’s premier building scientists to conduct
research and bring knowledge to builders to help them build better homes. This
knowledge has been gained from private/public partnerships involving builders all
over the country working with DOE. Many builders have adopted the program’s
principles and improved the performance of their houses and companies. Over 250
builders and venders have partnered with Building America, including five of the
largest 10 builders in the nation. This best practices guide contains results from this
research in a form that your company can immediately build into your homes to
increase efficiency, comfort, and durability. Learn more about Building America
at www.buildingamerica.gov.
MARKETERS
Energy efficiency
delivers the value that
customers demand
SITE PLANNERS
& DEVELOPERS
Properly situated houses
pay big dividends
DESIGNERS
Well-crafted designs
capture benefits for builders,
buyers, and business
SITE SUPERVISORS
Tools to help with
project management
TRADES
Professional tips for fast
and easy installation
CASE STUDIES
Bringing it all together
QUICK TIPS | MANAGERS
• Some of the most successful builders in the industry are working with
Building America.
• Applying the Building America process can: cut your production costs,
reduce risks, improve your bottom line, help make you a market leader, and
turn your customers into lead generators.
• This document gets you and your company started.
• ENERGY STAR® can help you market your new and improved product.
Building America Best Practices Series: Volume 4 – Builders and Buyers Handbook for
Improving New Home Efficiency, Comfort, and Durability in the Mixed-Humid Climate
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Managers
FIGURE 1: A small sampling of Building America’s 250 partners
Building America Partner
Ranking among Top 100 Builders
Pulte Homes
2
Centex Corp
4
Beazer Homes USA
6
The Ryland Group
7
K Hovnanian
9
Shea Homes
13
Weyerhaeuser Real Estate Company
16
Habitat for Humanity International
17
“My family and I set out to
re-engineer our company.
Now we have fun and we
love what we are doing. And
we’re producing quality homes
that are eco-friendly and
energy efficient.”
Jeff Simon, Executive Vice
President of Operations for
Veridian Homes
Source: Builder ONLINE, 2005
The Business Case for Building Science and Energy Efficiency
Why are all these builders working with Building America? The answer is simple –
Working with Building America can enhance your company’s bottom line. The Building
America process and systems approach embraces building science, component technology
and the system approach for house design and construction. The benefits include:
• Cost savings from making the best materials and equipment choices
• Reduced risks, increased productivity, and fewer callbacks
• Greater profit margins on energy efficiency and other upgrades
“I’m building my own home
now and I’m putting in many
of these improvements—did
the roof shielding, low-e
windows, on-demand water
heater, sealing all of the wall
penetrations.”
Michelle Horstemeyer, a lead
builder for John Wieland Homes
• Competitive advantage in the marketplace
• Customer satisfaction and referrals.
More information on each of these points is presented below. But boosting the bottom
line isn’t the only reason builders build quality, efficient homes. Builders tell us it boosts
their pride in their craft, increases the morale of their workforce, and gives them a good
feeling at the end of the day, knowing they’re doing their part to help the environment.
Properly Choosing Materials and Equipment
Building science offers many tools to help you pick out the right materials and size
them correctly, and to help make sure you are using them to build the right product.
Explanations and suggestions on building systems, designs, and trade-offs are in the
Designers
chapter of this document. The costs of some measures can be more than
what you are currently spending. The idea is to use the materials best suited to the job
and to size equipment accordingly. Higher prices in one area can be at least partially
offset with savings in other areas. Costs for all building materials can vary tremendously
in their own right, but your level of experience and design choices have a large bearing.
For comparison, some builders find they experience no overall increase in materials
costs to offer an energy-efficient package, but others suggest added costs of up to $1,500
per home. In the Designers
chapter, we show one example of costs and savings that
resulted in about $550 in savings for the design used by a Building America partner in the
mixed-humid climate. Read on to find out how this investment can add to your bottom line.
Building America Best Practices Series: Volume 4 – Builders and Buyers Handbook for
Improving New Home Efficiency, Comfort, and Durability in the Mixed-Humid Climate
“Construction companies
considering Building America
will realize that any additional
costs in construction are minor
and will be recouped through
higher sale prices and
quicker sales.”
Michael Bier, Housing Director of
the Detroit Shoreway Community
Development Organization, a
Cleveland development built with
Building America guidance.
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Managers
Reduced Risks, Increased Productivity, and Fewer Callbacks
These benefits follow closely from selecting and properly using the right materials and
equipment. Making a change in your process may take extra time the first few times
you try it, but once established, the payoffs can be significant.
One of the great values of using Building America approaches is that they were
designed to solve construction problems, such as moisture degradation and mold
growth, that plague builders. More than 10,000 mold cases are now pending
nationwide, with an increase in cases of more than 300% since 1999 (Insurance
Information Institute as reported in Wood and Clift, 2003).
Applying building science reduces the risk of big problems and helps to eliminate the
more mundane defects that cost money to fix. If you reduce the time your crews are
working on callbacks, you increase the time they can be working on new product.
From an Economic Standpoint, Everyone Wins
As a manager, watching your profit margins is a full-time job. The structure of your
business and emphasis you place on consistency determines how much profit you get
from options packages. Some builders choose to incorporate energy efficiency and
health and comfort options into their base price; others include them as options with
a profit margin similar to other premium add-ons. Whichever approach you use,
the experience of other builders suggest that customers place great value on energy
efficiency and will pay to get it.
Profit margins vary substantially from company to company. A National Association
of Homebuilders report (1999) and Professional Builder magazine (2003) suggest a net
profit margin of about 10% on overall house construction. This number is consistent
with publicly traded homebuilding companies. Six companies’ annual financial reports
to the Securities Exchange Commission over 2001 and 2002 reported net profit
margins ranging from 4.2% to 9.6%. Gross profit margins over this same time period
ranged from 7.4% to 19.2%. In comparison, builders report they have gained about a
30% profit margin on efficiency upgrade packages.
In the Homeowners
chapter, we offer an example showing how energy-efficient homes
end up costing less for consumers on a monthly basis when both the mortgage and energy
expenses are taken into account. Consumers can either pocket these lower costs or use
them to buy a more expensive home. Any upgrades translate into added profit.
In short, builders can increase their profits at the same time that consumers lower
their costs. From an economic standpoint, everybody wins.
Customer Satisfaction and Referrals
Customer satisfaction matters to your company’s future and energy efficiency matters
to your customers. Pulte is a Building America Partner that brands its homes using
ENERGY STAR. In 2004 J.D. Power and Associates, a market research firm, gave
Pulte’s various divisions top rankings in 14 of the 25 U.S. markets it surveys, including
Detroit, Minneapolis/St. Paul and Philadelphia, and placed it among the top 3
companies in 23 of 25 markets including Chicago.
Building America Best Practices Series: Volume 4 – Builders and Buyers Handbook for
Improving New Home Efficiency, Comfort, and Durability in the Mixed-Humid Climate
“We have seen a direct impact on
our quality through the Building
America Program. We are able
to build a better product because
of our consistent approach
[in implementing Building
America practices],”
Josh Robinson, Pulte Sun Lakes
project manager and a Pulte Vice
President (Vice President of
Operations for Pulte, North Inland
Empire Division of Southern California)
“This makes absolute sense and
it is a very easy thing to sell
to customers.”
Les Bluestone, owner of Blue Sea
Development Company in New York
“Building America’s technical
assistance on building science
helped us to reduce callbacks by
70% in our Chicago Division.
That’s a tremendous savings for
our company and means our
customers are happier with
their homes.”
Frank Beasley, V.P. of Building
Science, Town and Country Homes
“Since partnering with Building
America in 2001, Artistic
Homes reports that its liability
for defects and damage has
been reduced, as has the
number and cost of warranty
calls; ‘meanwhile, customer
satisfaction is at an all-time
high,’ according to Max Wade
of Artistic. The production
builder has produced more than
2000 ENERGY STAR homes in
Albuquerque, NM, since 2001.”
As reported in Builder Magazine 11/1/03
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Managers
Pulte Phoenix, which J.D. Powers ranked first in that local market, also won the
Diamond Award from Professional Builder Magazine and NRS Corp., a market research
company that works with the home building industry. Pulte had the top customer
satisfaction for production builders of nearly 300 builders in the nation.
Paul Cardis of NRS, a market research expert, notes that “customer satisfaction is
important for many reasons, not least is that satisfied customers refer future customers
and the conversion rate for referrals is twice that of non-referred shoppers.”
The September 2003 issue of
Professional Builder provides
six top reasons why customers
are willing to recommend a
builder. Energy efficiency
is first among the reasons
related to product.
Consumers Expect More
Buyers want energy efficiency and
they are willing to pay for it. A 2001
Professional Builder Magazine survey
found that energy efficiency is the
number one upgrade that homebuyers
seek in a new home. Nearly 90% of new
homebuyers in the survey were willing
to spend more for energy efficiency
features (Johnston 2001). Consistent
with this study, the National Association
of Homebuilders (NAHB) found that
consumers would be willing to spend
up to $5000 more on a new home if
it saved them $1000 on their annual
utility bills (NAHB 2002). And Pulte’s
customers in Phoenix rated energy
efficiency as the most important
product-related reason for referring
their contractor to new buyers.
“Nearly 93%
of buyers of Pulte Homes in
Phoenix had made at least one
positive recommendation.”
Atlantic Design, a Building America partner,
was recognized as a 2000 EPA Builder of the
Year for its quality energy-efficient construction.
Competitive Advantage in the Marketplace
One of your key goals as a manager is to gain competitive advantage in the marketplace.
The technologies described in this packet can give your company a technological edge.
One easy way to tell the public about your new product is to partner with ENERGY
STAR. ENERGY STAR is a nationally recognized branding program sponsored by
the U.S. Department of Energy and the U.S. Environmental Protection Agency.
Consumers trust the ENERGY STAR logo to tell them whether their product is
energy efficient. Participating in ENERGY STAR is easy and it gives you an effective
way to distinguish your product from your competition’s. Over 2,000 builders work
with ENERGY STAR in the United States. And half of the 100 largest builders in the
nation have at least one division building ENERGY STAR qualified homes.
ENERGY STAR qualified homes are independently verified to be at least 30% more
energy efficient in space conditioning and water heating than homes built to the
1993 national Model Energy Code or 15% more efficient than the state energy code,
whichever is more rigorous. These savings are consistent with the practices described in
this best practices manual. Heating, cooling, and hot water energy use make up about
half of a household’s total utility bills.
Building America Best Practices Series: Volume 4 – Builders and Buyers Handbook for
Improving New Home Efficiency, Comfort, and Durability in the Mixed-Humid Climate
Professional Builder Magazine,
September 2003, p. 67
“Our attention to energy
efficiency is what really makes
Pulte’s homes stand out.”
Les Woody, Pulte Phoenix
Director of Customer Service
“Building America helps us
with our reputation within
the building community. Our
reputation on the street is that
if you want a good quality
home you go to Pulte.”
Alan Kennedy, Vice President of
Construction for Pulte Tucson
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Managers
Take the Next Step
This information packet is designed to give your company all the information you need
to start using the Building America systems approach in the mixed-humid climate. The
techniques described will help you avoid many of the problems plaguing all builders in
the mixed-humid climate.
Make sure your team reviews the sections prepared for each of your company’s capability
areas: marketing, site planning, design, building site supervision, and the trades. This
information will help your company compete in an increasingly complex and risky
market. Following the design practices discussed in the Designers
chapter and
the inspection and testing procedures outlined in the Site Supervisors
chapter will give
you the technical information you need to build your business. Find more information
on ENERGY STAR in the Marketers
chapter and on the Web at www.energystar.gov.
“When Mrs. Perez doesn’t have
heat on New Years Eve, the
phone rings in my house. If I
don’t have to send people back
on callbacks, that is certainly
a savings to me, it’s worth the
peace of mind.”
Les Bluestone, owner of Blue Sea
Development Company in New York
Case Studies
Take a look at the case studies at the end of the book. All offer examples of how
builders achieve profitable energy efficiency in the mixed-humid climate.
Sources & Additional Information
•
Builder Magazine. Healthier Profits Special Advertising Section. November 2003
•
Builder ONLINE, 2005. Builder 100 Listing. www.builderonline.com
•
California Energy Commission has a series of brief online videos that describe
why energy efficient building makes business sense. You can find and play the
videos at www.energyvideos.com; click on “Beyond the Codes”.
•
J.D. Power and Associates. J.D. Power and Associates 2003 New Home
Customer Satisfaction Study. West Lake Village, California. 2003.
• Johnston, David. 2000. “Buyer Green.” Professional Builder, September 2000.
www.housingzone.com
•
National Association of Home Builders. The Truth About Regulatory Barriers.
Washington, D.C. 1999.
• National Association of Home Builders. 2002. What 21st Century Home Buyers
Want. NAHB, Washington, D.C.
•
Professional Builder. “Where are the Giants Headed? Industry Consolidation
is Changing the Way Even the Smallest Production Builders Do Business, but
How Far it Will Go is Still Open to Debate.” April 2003. www.housingzone.com
•
Professional Builder. “Customer Service Standard Setters.” September 2003.
www.housingzone.com
•
Wood, C., and L. Clift. “Seven Wonders of the Construction World.”
ProSales. October 2003, pp. 28-44.
Building America Best Practices Series: Volume 4 – Builders and Buyers Handbook for
Improving New Home Efficiency, Comfort, and Durability in the Mixed-Humid Climate
You can learn more
about Building America
and download additional
copies of this document at
www.buildingamerica.gov
Version 1, 9/2005 • MNG-5
Marketers
Energy Efficiency Delivers the Value that Customers Demand
INTRODUCTION
By selling homes you bind your company to its customers. Your work enables the
company to capitalize on the benefits of its investments, including those made
in energy efficiency. And you are the ones who help homeowners understand the
quality, value, and economy represented by your product.
HOMEOWNERS
Shopping for value,
comfort, and quality
MANAGERS
ENERGY STAR Qualified Homes: Telling Your Story
An easy way to sell energy-efficient homes is to become an ENERGY STAR partner.
Even if you build or sell great houses, if they aren’t ENERGY STAR qualified, it’s
hard for your customers to know how much efficiency they are getting. ENERGY
STAR helps you to tell your story. The ENERGY STAR logo makes it easy to tell
consumers you are selling a superior product. And the ENERGY STAR program
offers much in the way of advice and examples of how to use the logo. Differentiate
yourself by offering a home that is certified to be more efficient—and better for the
environment—than standard models.
®
To find out more about marketing with the
ENERGY STAR logo visit the program’s
Web site at www.energystar.gov. You’ll find
information about before-sales marketing,
point-of-sale techniques, and building
ongoing relationships with your customers.
Much of the information comes from
successful techniques used to sell ENERGY
STAR homes across the nation. Tools on
the Web site will help you instantly craft
your message and prepare sales materials.
Taking action in
your community
Putting building
science to work for
your bottom line
MARKETERS
Energy efficiency
delivers the value that
customers demand
SITE PLANNERS
& DEVELOPERS
Properly situated houses
pay big dividends
DESIGNERS
Well-crafted designs
capture benefits for builders,
buyers, and business
ENERGY STAR offers a marketing platform
that home builders can use to recognize that
you offer truly energy efficient homes.
SITE SUPERVISORS
Tools to help with
project management
TRADES
QUICK TIPS | MARKETERS
• Energy efficiency, and the quality that comes with it, gives you a
competitive advantage.
Professional tips for fast
and easy installation
CASE STUDIES
Bringing it all together
• ENERGY STAR can help you capitalize on your competitive advantage,
produce marketing materials, and connect with buyers.
• Your customers see energy efficiency as a sign of value.
• Some of the biggest builders in the country have learned that energy
efficiency can turn existing customers into new sales leads through
customer satisfaction.
• Learn how industry leaders sell new energy-efficient homes.
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Marketers
Increase Customer Satisfaction and Let Your Customers Sell Your Product
Wouldn’t it be great if, for every home you sold, you could add a new sales associate
to your staff to sell even more?
That’s what energy efficiency can do for you. Happy customers will sell your products
for you. And energy-efficient homes make happy customers. Compared to standard
homes, energy-efficient homes cost less to own, are more comfortable to live in, and
require less maintenance.
The builder with the top customer satisfaction rating in the nation in 2003, Pulte
Homes of Phoenix, is a Building America partner offering ENERGY STAR qualified
homes. Pulte’s Phoenix division has had one or more positive referrals from 93% of its
homebuyers. The conversion rate for shoppers referred in this way is twice that of
non-referred shoppers. Homeowners talk, and word of mouth is a powerful selling
tool. Some experts, in fact, say word-of-mouth is the most effective selling tool because
it carries with it the credibility of a
trusted third party, such as a friend
or relative. Add to that the fact that
many potential buyers are skeptical
of traditional advertising, and it’s
no surprise that 10% to 30%, and
sometimes more, of builders’ sales
come from referrals (Farnsworth
2003). The best way to sell homes is
to let your customers do it for you.
See the Managers
chapter for
Shoppers love to peer into the attic through this
information on the great customer
viewing window in a Building America model house
satisfaction ratings received by
by Cambridge Homes. Shoppers can see the special
builders selling ENERGY
insulation, and the thermometer tells them how cool
STAR homes.
the attic stays.
“If you don’t tell your story,
you give it away!”
Vern McKown, President,
Ideal Homes
“The demand for energyefficient housing is growing.
To meet today’s market
demand, DSCDO plans
to incorporate Building
America principles in all
of the homes it develops.”
Michael Bier, Housing Director of
the Detroit Shoreway Community
Development Organization,
referring to EcoVillage an urban
infill project they built in Cleveland
using Building America principles.
Sell the Value that Home Buyers Expect
Market research shows:
• Energy efficiency is the number one upgrade sought by homebuyers
of new homes (Professional Builder Magazine 2001)
• Nearly 90% of new homebuyers are willing to spend more for
energy efficiency (Johnston 2000 and NAHB 2002)
• Buyers rate energy efficiency as a home builder’s most important
product-related reason for referring new customers (Professional
Builder Magazine 2003)
How Industry Leaders Sell Energy-Efficient Homes
The NAHB Research Center sponsors an annual award competition called the
Energy Value Housing Award. The Center has compiled the winning builder’s
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Marketers
marketing techniques into a document that can be purchased on the Web at
www.nahbrc.org/tertiaryR.asp?CategoryID=1705&DocumentID=3404 (Sikora 2002).
Here are some of the best practices recommended by the NAHB Research Center and
other sources:
• Educate customers and sales professionals. Show buyers how living in
an energy-efficient home will benefit them with lower household costs.
The ENERGY STAR Web site has an example as does the Homeowners
chapter. Vital to customer education is an informed sales staff and team of
local sales professionals.
• Walk-throughs and model homes can be invaluable educational tools for
both buyers and sales staff. Model homes with display cutaways of energy
features such as insulated attics and wall sections help them understand the
energy-efficient construction process. Use labels, flags, and banners to create
a fun self-explanatory message to give buyers a focus while they drive or
walk the development. Recent research suggests just how important model
home, models of house features, and other educational tools are to shoppers
(Farnsworth 2003).
“Our Building America homes
are selling as soon as we can
build them. In fact, we have
purchase agreements for most
before we finish them.”
Lisa Rotvold, Director of the
not-for-profit Eastern Dakota
Housing Alliance
• Training sessions can be an effective tool for educating sales staff and
professionals. Use slides, sample products, and energy bills as aids.
• One way to educate consumers is to emphasize an energy-efficiency upgrade
when signing the final papers. One builder has a wall of testimonials, photos,
and utility billing history in his waiting room. All prospects are given an
opportunity to view this “wall of fame” before the final sale is made. Another
builder has the buyer meet with the building site supervisor after the sale is
made. This person gives them one more chance to sign up noting, from a
builders’ perspective, what a better house they will get (Rashkin 2002).
• Publications are an educational tool that customers and sales professionals can
take home. Develop your own brochures or books or give away reprints of
magazine articles, ENERGY STAR brochures, or Building America brochures.
Don’t overlook vendors and trade associations. They can provide excellent
materials, often at no charge. For example, excellent information on window
performance is available at the Efficient
Windows Collaborative Web site at
www.efficientwindows.org/index.cfm.
Also, give potential buyers a checklist
so they can compare the energy saving
measures in your homes with those of
other builders. A sample is included
in the Homeowners
chapter.
“This [building to Building
America principles] was a way
for us to not only give back
to our community but to give
back to our environment.
There were not a lot of builders
at the time who were building
their homes Green Built or
ENERGY STAR; when we
jumped on board, it was a
way for us to raise the bar
and take that next step.”
Jeff Simon, Veridian’s Executive
Vice President of Operations
• Advertising can be used to explain the energy-efficiency advantages and
distinguish builders from their competition. The ENERGY STAR Web site
has useful information for designing advertising.
• The Internet and compact disk formats are another forum for presenting all
of your education and advertising messages. Some marketers suggest that all
builders should have a Web site, even if it is simple and offers only limited
information. CDs with brochures or slide shows can be given to potential
buyers to take home and replay your message.
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Marketers
• Seek out free publicity. Nothing is more cost effective than sending a news
release to local media to announce business news and other company activities.
News releases can cover your company’s involvement in educational activities,
for example, teaching school children about energy efficiency or other
charitable actions.
• Offer energy-efficiency guarantees. Energy performance guarantees can
help convince buyers that energy savings are real. Partnerships with outside
companies can help to establish guarantees. For example, some insulation
manufacturers offer home inspections, tests, and cost guarantees.
• Make buyers aware of energy-efficient mortgages.
• Take advantage of the testing data available on your homes. If your company
follows the best practices in this guide, you will have blower door and duct
tightness test data and a HERS score to share with buyers. Use these data to
inform your customers and differentiate your houses. If you can not provide
testing, make it available as an option for homebuyer’s purchase.
Participate in ENERGY STAR and other partnerships. ENERGY STAR and Building
America can provide technical guidance through publications and their Web sites.
Partnering with ENERGY STAR cements your company’s commitment to energy
efficiency and gives you access to the ENERGY STAR brand.
Sources and Additional Information
• Farnsworth, Christina. 2003. “The Weakest Link.” Builder Magazine,
December 2003. www.builderonline.com/article-builder.asp?channelid=55&ar
ticleid=375&qu=consumer+survey
• Johnston, David. 2000. “Buyer Green.” Professional Builder, September 2000.
www.housingzone.com
• Professional Builder. “Customer Service Standard Setters.” September 2003.
www.housingzone.com
• National Association of Home Builders. 2002. What 21st Century Home Buyers
Want. NAHB, Washington, D.C.
• Rashkin, Sam. 2002. “Surprise! Energy Efficiency Sells without Rebates:
Results of Mainstream Builders Selling ENERGY STAR Labeled Homes”
Proceedings of the 2002 ACEEE Summer Study on Energy Efficiency in Buildings,
Washington D.C.
• Sikora, Jeannie. 2002. Energy Value Housing Award Guide: How to Build and
Profit with Energy Efficiency in New Home Construction. National Association
of Home Builders Research Center, Upper Marlboro, MD.
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Site Planners
Properly situated homes pay big dividends
INTRODUCTION
The National Association of Home Builders (NAHB) estimates that 1.6 million new
homes will be built each year over the next decade (NAHB 2002a). How these new
developments are designed will have a major impact on energy use, the environment,
and customer satisfaction.
Developers and site planners can set the stage for efficient communities and can
direct builders to protect a community’s value through quality building practices.
The sun is the main source of heat in all homes. By looking at how houses receive
sunlight, site planners can help optimize how much solar energy is available to heat
a house, and minimize the heat that must be removed with air conditioning.
In the mixed-humid climate, planners should do all they can to orient buildings to
use the sun for daylighting and solar gain. Site planners have two important tools to
help manage solar gain: lot orientation and shade trees.
Lot Orientation
As planners map out lots and roads, the relationship between buildings and the sun
should be key. Just as you lay out roads to allow houses to take advantage of great
views, or to work around hillsides and other landscape features, also consider how
road design, lot lines, and orientation will influence the way that houses face the sun.
Lot lines and roads should be situated to minimize home exposure to east and west.
Plan your subdivision so that the longer sides of the houses will face north or south.
Streets should be positioned in an east-west direction. Proper orientation can result in
substantial savings of heating and cooling costs, depending on specific site conditions
and house designs. With proper planning, there may be no added costs to the builder
for good orientation.
Lot orientation is especially important if solar heating or electric generation systems
are planned. Inexpensive tools can help assess how much solar energy will be blocked
by obstacles on a particular site. Low-cost tools for solar assessments are described in
the Designers
chapter in the section about windows.
Taking action in
your community
HOMEOWNERS
Shopping for value,
comfort, and quality
MANAGERS
Putting building
science to work for
your bottom line
MARKETERS
Energy efficiency
delivers the value that
customers demand
SITE PLANNERS
& DEVELOPERS
Properly situated houses
pay big dividends
DESIGNERS
Well-crafted designs
capture benefits for builders,
buyers, and business
SITE SUPERVISORS
Tools to help with
project management
TRADES
Professional tips for fast
and easy installation
CASE STUDIES
QUICK TIPS | SITE PLANNERS
Bringing it all together
• West-facing windows should be minimized.
• Deciduous trees are preferred for winter solar gains.
• Take advantage of prevailing breezes from lakes, the ocean, or other
geographical features.
• Properly grade your development to take water away from structures.
• Use sustainable site and landscaping practices.
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Site Planners
FIGURE 1: Plan subdivision lot lines and roads for predominantly north
and south orientation - place houses within lots to take advantage of solar access
N
N
Typical Subdivision
N
Subdivision with Predominantly
North- and South-Facing Sites
Adapted from Viera et al. 1992. p.3-5
Lot orientation provides access to the sun, but window selection and shading are the
controls that manage solar gain. A small Solar Heat Gain Coefficient (SHGC) limits
the entry of solar energy. Some Building America teams recommend a SHGC of 0.35.
(See the Designers
chapter in the section about windows).
In addition to helping manage the sun and providing a marketing advantage, proper
street design can reduce the environmental impacts of runoff, encourage walking and
bicycling, and discourage speeding by through-traffic.
Subdivision planning can also help to gain cooling benefits from breezes. Houses and
other buildings that are tightly packed may create a wake in the wind that is four to five
times the buildings’ eave height.
Curved streets and staggered lots can assist in preventing wind disturbance. Trees
can help to keep breezes cool as described in the next section. Taking advantage of
breezes will reduce cooling costs. Wind conditions at any individual site may differ
considerably from regional averages. Local geography such as ocean beaches, lakes,
fields, golf courses, parks, and malls can influence local breezes.
FIGURE 2: Wind wake of a typical house
8'
Source: Viera et al. 1992. p.3-7
Wind Wake of a Typical House
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Site Planners
Shade Trees
Tree preservation brings many benefits, one of which is increased salability. Native trees
are most beneficial to the environment. The NAHB reports in its survey of buyers, What
21st Century Homes Buyers Want, that over 68% of respondents in the Northeast, and over
80% in the South Atlantic, South Central, and West rated trees as essential or desirable
(2002b, page 61). American Forests and the NAHB (1995) found that mature trees may
add from $3,000 to $15,000 to the value of a residential lot.
Trees also bring value by providing shade. It is far better to prevent solar energy
from reaching a house in summer than to attempt to manage it once it enters. Shade
trees block summer sunlight before it strikes windows, walls, and roofs, dissipating
absorbed heat to the air where it can be carried away by the breeze. If photovoltaic or
water heating systems will be added, trees must be placed not to shade these systems.
Deciduous trees work best for letting the sun shine through in winter but providing
shade in summer.
Truly cool neighborhoods have trees. A study in Florida has shown that a subdivision
with mature trees had cooler outside air with less wind velocity than a nearby
development without trees (Sonne and Viera 2000). The development with a tree
canopy had peak afternoon temperatures during July that were 1.1°F to 3.1°F
(± 0.7°F) cooler than the site without trees. The total effect of shading, lower summer
air temperature, and reduced wind speed can reduce cooling costs by 5% to 10%
(McPherson et al. 1994).
Trees are most effective when located to cast shade on the roof, windows, walls, and
air conditioners, and when located on the side of the home receiving the most solar
exposure. Shade to the southwest and west is especially important for blocking peak
solar gain in the summer in late afternoon. Depending on the species, trees more than
35 feet from the structure are probably too far away for shade. Plants too close to air
conditioners or heat pumps can plug coils.
FIGURE 3: Configuration of shade trees
N
Windbreak Shrubs
Shrub Shading of
Lower Wall
Deciduous
Trees
Source: Viera et al. 1992. p.3-8
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Site Planners
Other Steps
In addition to orientation and the use of trees, many other steps can be taken during
site planning to make developments user and earth friendly.
Site Grading
Proper site grading directs surface water away from building foundations and walls.
The steeper the slope away from the building, the better the water will drain. Slabs and
crawlspaces should always be above the surrounding grade. Basement floors should be
higher than the surrounding drainage system. Driveways, garage slabs, patios, stoops,
and walkways should all drain away from the structure. See EEBA’s Water Management
Guide (Lstiburek 2003) for more information. Additional information on moisture
management is also available in the Designers
chapter.
FIGURE 4: Drain all water away from the structure
Drain Building
Drain Roof
Drain Wall
Drain Materials
Drain Components
Drain Openings
Drain Site
Drain Ground
Drain Site
Drain Ground
Source: Lstiburek, J.W. 2003. p.4
Sustainable Development
Builders who choose to advertise their “green” designs have found that buyers are
willing to pay for environmental features.
Features that help to conserve the natural environment can include:
• Orienting lots to best manage energy and light from the sun.
• Land planning that preserves the natural environment and
minimizes land disturbance.
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Site Planners
• Site design that minimizes erosion, paved surfaces, and runoff.
• Preserving and protecting trees and natural vegetation.
• Conserving water indoors and out.
• Designing energy efficiency into houses.
• Selecting materials that are durable and recyclable, or created from recycled
products, and considering the energy that goes into making products.
• Recycling construction materials and reducing on-site waste.
Good places to start on sustainable development are found in Southface Energy
Institute’s Sustainable Design, Construction, and Land Development Guidelines for the
Southeast (Brown 2000), Rocky Mountain Institute’s Green Development: Integrating
Ecology and Real Estate (Wilson, et. al. 1998), the NAHB’s Building Greener: Building
Better: The Quiet Revolution (NAHB 2002c), the Sustainable Building Council’s Green
Building Guidelines (SBIC 2003), www.lid-stormwater.net, a U.S. EPA-sponsored
Web site with tools for watershed management, DOE’s Smart Communities Network
at www.sustainable.doe.gov, and A Guide to Environmentally Friendly Landscaping:
Florida Yards and Neighborhoods Handbook (U of F 2003). Be sure to search local and
updated sources for relevant information.
“What we tell buyers is that
we sell value…it’s about high
standards in every aspect of
home building…The whole
idea is to get builders all over
the country more concerned
about building this way—it’s
about energy efficiency, indoor
air quality, waste recycling,
water recycling, better
planning—it all leads to
better development.”
GW Robinson,
President of GW Robinson
Sources and Additional Information
• American Forests and the National Association of Homebuilders. 1995.
Building Greener Neighborhoods: Trees as Part of the Plan. NAHB,
Washington, D.C.
• Brown, w. 2000. Sustainable Design, Construction, and Land Development
Guidelines for the Southeast. Southface Energy Institute and Oak Ridge
National Laboratory, Oak Ridge, Tennessee. www.southface.org/home/
sfpubs/large-pubs/Sustainable_community_development.pdf
• Lstiburek, J.W. 2003. Water Management Guide. Energy and Environmental
Building Association, Minneapolis, Minnesota. www.eeba.org
• McPherson, G.E., D.J. Nowak, and R.A. Rowntree (eds). 1994. Chicago’s
Urban Forest Ecosystem: Results of the Chicago Urban Forest Climate Project.
U.S. Department of Agriculture, Forest Service, Northeastern Research
Station, www.f.fed.us/ne/newtown_square/publications/
technical_reports/pdfs/scanned/gtr186a.pdf
G.W. Robinson pipes recycled
irrigation water to cut water
use and costs to homeowners at
the Cobblefield development in
Gainesville, Florida.
• National Association of Homebuilders. 2002.a Builder’s Guide to the APA’s
Growing Smart Legislative Guidebook. NAHB, Washington, D.C.
• National Association of Home Builders. 2002b. What 21st Century Home
Buyers Want: A Survey of Customer Preferences. NAHB, Washington, D.C.
www.BuilderBooks.com
• National Association of Homebuilders. 2002c. Building Greener: Building
Better: The Quiet Revolution. NAHB, Washington, D.C.
Building America Best Practices Series: Volume 4 – Builders and Buyers Handbook for
Improving New Home Efficiency, Comfort, and Durability in the Mixed-Humid Climate
Version 1, 9/2005 • PLN-5
Site Planners
• Sustainable Buildings Industry Council (SBIC). 2003. Green Building
Guidelines: Meeting the Demand for Low-Energy, Resource-Efficient Homes. U.S.
DOE. Washington, D.C. document available at www.SBICouncil.org.
• Sonne, J.K. and R.K. Viera, 2000. “Cool Neighborhoods: The Measurement
of Small Scale Heat Islands.” Proceedings of the 2000 Summer Study on Energy
Efficiency in Buildings, American Council for an Energy-Efficient Economy,
Washington, DC. www.fsec.ucf.edu/bldg/pubs/pf363/index.htm
• University of Florida (U of F). 2003. A Guide to Environmentally Friendly
Landscaping: Florida Yards and Neighborhoods Handbook. Edited by Christine
Kelly Begazo and Rebecca McNair. Gainsville, FL. http://hort.ufl.edu
• Viera, R.K., K.G. Sheinkopf, and J.K. Sonne. 1992. Energy-Efficient Florida
Home Building, third printing. Florida Solar Energy Center, FSEC-GP-33-88,
Cocoa Beach, Florida.
• Wilson, Alex, Jenifer L. Seal, Lisa A. McManigal, L. Hunter Lovins, Maureen
Cureton, William D. Browning. 1998. Green Development: Integrating
Ecology and Real Estate. Rocky Mountain Institute, Old Snow Mass, CO.
www.rmi.org/sitepages/pid220.php
Web Sites Not Included with Published Documents Above
• www.xeriscape.org
• www.lid-stormwater.net
• www.sustainable.doe.gov
• www.sustainabledesignguide.umn.edu/MSDG/site.html
Building America Best Practices Series: Volume 4 – Builders and Buyers Handbook for
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Designers
Well-crafted designs capture benefits
for builders, buyers, and business
Even good builders can have bad results if they are working toward the wrong product.
Designers have the job of giving builders the opportunity to do the right thing well.
“If you do the wrong things with good materials and good workmanship, it is still
wrong. You must do the right thing with good materials and good workmanship.”
Joseph Lstiburek, Building Science Corporation
QUICK TIPS | DESIGNERS
• Building America brings you the results of research, real-world experience, and
dialogue with builders from over 25,000 homes nationwide (as of early 2004).
• System design and building science offer you tools and techniques to
improve housing performance without sacrificing style and appeal, avoid
problems plaguing new homes, find cost savings to help your company’s
bottom line, and give consumers satisfaction in their investment.
• Seek the help of a home energy rating professional or engineer to avoid reinventing
many of the solutions that have already been found and optimize your designs.
• Review the many technologies discussed in this chapter for help in selecting
the applications right for you.
Building Science and the Systems Approach
Perhaps the most important step in designing any form or function is recognizing
that the design is for the entire product. No one piece can be changed without
affecting all related pieces. This simple proposition applies to all systems and allows
for all kinds of trade-offs. In cars, without any loss in performance, lightweight
frames may be translated into smaller brakes, a smaller engine, and smaller tires.
Or, that same change may be used to produce more speed.
In houses, this systems approach recognizes the interaction of windows, attics,
foundations, mechanical equipment, and all other components and assemblies.
Changes in one or a few components can dramatically change how other components
perform. Recognizing and taking advantage of this fact, and applying appropriate
advances in technology to components, can result in cost and performance payoffs,
both for the builder and buyer of new homes.
INTRODUCTION
Taking action in
your community
HOMEOWNERS
Shopping for value,
comfort, and quality
MANAGERS
Putting building
science to work for
your bottom line
MARKETERS
Energy efficiency
delivers the value that
customers demand
SITE PLANNERS
& DEVELOPERS
Properly situated houses
pay big dividends
DESIGNERS
Well-crafted designs
capture benefits for builders,
buyers, and business
SITE SUPERVISORS
Tools to help with
project management
TRADES
Professional tips for fast
and easy installation
CASE STUDIES
Bringing it all together
Building America has embraced the systems approach and combined it with
the technology development and testing that make up building science. As
with other scientific disciplines, building science provides an intelligent approach to
understanding complex systems and diagnosing problems. Over time, knowledge,
tools, and tests are developed that make the science and the product more efficient
and more powerful. You can learn more about the U.S. Department of Energy’s
(DOE) Building America program at www.buildingamerica.gov. (Adapted from
Florida Solar Energy Center Web site www.fsec.ucf.edu/bldg/science/basics/index.htm)
Building America Best Practices Series: Volume 4 – Builders and Buyers Handbook for
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Designers
Four steps can help to manage risks and take advantage of system trade-offs.
1) Give builders the right target. Recognize you are designing a complete product—
a system—and ensure the product is right for the mixed-humid climate.
2) Take care of the basics. The basics are proven, cost-effective technologies that
include good windows, insulation, moisture management, and ventilation. Make sure
the house has adequate overhangs for shade and rain deflection. Guidelines for many
of the basics are included later in this chapter.
3) Take only what you need. Size heating and cooling equipment, ducts, and fans to
match the load. If equipment sizing is normally done by a subcontractor, ensure the sub
uses the procedures listed in this document to properly size equipment. Proper sizing of
heating and cooling equipment is a huge opportunity to save money and increase profit.
4) Put everything in its place. Be sure there is a place for everything the house requires
and show it on your plans. Do not leave it to chance where ducts will be placed or
even where plumbing will run. If there are places that should not be tampered with,
for example a duct chase, make it clear the space is off limits to plumbers, electricians,
and others who need to create routes through buildings.
Building Science and the Systems Approach: Prevents Problem
“Understand the theory of your
construction…then be sure
to question your engineer (or
subcontractor) as to whether
it’s all really necessary. If
you don’t get a straight,
understandable answer, find
an engineer who will give you
one. Remember, it doesn’t cost
the engineer a penny to overdesign. But ultimately someone
foots the bill.”
Tim Garrison, CEO of Construc
tionCalc, made an important point
about the cost of overdesigning
structural components. He is
quoted here because his point is
equally valid for HVAC and other
equipment (adapted from Nation’s
Building News Online, 27 April
2004, www.nbnnews.com).
Moisture, mold, and material degradation are examples of problems that building science can
help solve. High temperatures create a need for cooling. High humidity adds to discomfort and
is a source of moisture. Humid air and a cold surface result in condensation that can add up to
discomfort, material failure, and high repair costs.
Leaky ducts located in attics or crawlspaces create air pressure differences that can draw in humid
air through cracks and holes and deliver it into the house. Humid air inside a cool space encourages
the occupant to turn down the thermostat for more cooling. This cycle can result in moisture
forming as condensation on or in ducts, walls, and other assemblies. Accumulated moisture
supports mold growth and leads to rotting, warping, and staining.
The result is that a small problem in one assembly (leaky ducts) that is inexpensive to fix during
installation, can lead to big problems in framing, interior finish, and human health. Moisture
problems may have causes other than leaky ducts, but many unintended problems can be avoided
in a similar fashion.
Building Science and the Systems Approach: Reaps Rewards
There is more than avoiding problems to encourage you to use a systems approach. For example,
trade-offs from installing energy-saving measures can help save construction costs for heating
and cooling equipment. If good windows, adequate insulation, and efficient heating and cooling
equipment are installed, the heating and cooling equipment capacity can also be smaller than
typically used and shorter duct runs are possible. All of this can add up to reduced costs in heating
and cooling equipment that offset the cost of the other measures. Using trade-offs to improve
economics, durability, and comfort is essential to successful business and design.
The challenge to designers is to carefully select new technologies, consider their cost
and rewards for your overall system, and use the changes that make sense. Building
America has taken this systems approach to designing energy-efficient houses. This
document presents you with information that will give you a straight-forward approach
to designing houses that qualify for ENERGY STAR®. Design information is provided
for a variety of measures and components in the remainder of this section. Put in the
recommended measures and your houses should qualify. You may also qualify using
other trade-offs. Suggestions from Building America’s experience are also included that
will improve the health and comfort of your homes.
Building America Best Practices Series: Volume 4 – Builders and Buyers Handbook for
Improving New Home Efficiency, Comfort, and Durability in the Mixed-Humid Climate
You can learn more
about Building America
and download additional
copies of this document at
www.buildingamerica.gov
Version 1, 9/2005 • DES-2
Designers
The Cost of Doing Business
The cost of building homes is different for every builder. Technique, experience,
subcontractors, suppliers, and the size of purchases can all make a difference in how
much a home costs to build. Even a builder’s accounting methods can influence
how costs are reported. These variables all apply to energy-efficiency measures and
contribute to the difficulty of providing cost estimates that apply to more than a
limited example over a short period of time.
In addition to variability, other considerations apply to costs. First, the cost of higher
quality housing represents an added value and holds the potential of a higher profit.
Second, a tremendous benefit of the systems approach described above is that the costs
of energy-efficient measures can often be offset by savings in other areas. And finally,
buyers can recover any additional costs through reduced utility bills, increased resale
value, and for some, better mortgage terms.
FIGURE 1: Cost Comparisons of Energy Efficient Measures to Conventional Practice
in the Mixed-Humid Climate
COST COMPARISON TO CONVENTIONAL MEASURES
Less Cost
Conventional
More Cost
MIXED-HUMID CLIMATE
Advanced Framing
-$250 SAVINGS
• 2x6 walls with R-20 rather than 2x4 walls with R-11
Insulating Sheathing
+$300 ADDED COST
No Housewrap
-$300 SAVINGS
High-Performance Solar Control Windows
+$300 ADDED COST
Compact Duct System
-$300 SAVINGS
Right-Sized Air Conditioner
-$500 SAVINGS
Air Flow Retarder System
+$300 ADDED COST
No Poly Vapor Barrier
-$100 SAVINGS
Controlled Ventilation System
+$100 ADDED COST
Integrated Heating & Hot Water System
-$100 SAVINGS
-$550 SAVINGS
• In place of furnace
Some builders say that meeting
ENERGY STAR qualifications
does not increase their costs.
However, they must focus on
higher quality installations.
Other builders suggest add
itional costs up to $1,500 to
the consumer, but it’s unclear
if these values apply beyond
their experience. The chart
at left is based on a 1999
cost estimate for homes
built in mixed climates. The
example is intended to show
how costs and savings trade
off, rather than to provide
estimates of dollar savings.
COST DIFFERENCE
Source: Building America. 1999. Cost Saving System Trade-offs for Mixed Climates.
U.S. Department of Energy, Washington, D.C. www.buildingamerica.gov
Building America Best Practices Series: Volume 4 – Builders and Buyers Handbook for
Improving New Home Efficiency, Comfort, and Durability in the Mixed-Humid Climate
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Designers
HERS Ratings and Qualifying for ENERGY STAR
Best Practice: Building America recommends working with a Home Energy Rating
System (HERS) professional, architect, or engineer early in the design process to help
select and size materials and equipment. The building scientists can be especially
helpful in right sizing heating and cooling equipment. By forming a relationship with
a rater who later will inspect the construction site, designers can get valuable feedback
about what works and what house features require more detailed information for the
site supervisor and the trades. Find out more about HERS raters at www.natresnet.org.
The best use of a HERS rater involves working with your rater in creating your design.
When following this path, the rater analyses your construction plans, in addition to
at least one on-site inspection and test of the home. The plan review allows the home
energy rater to view technical information such as orientation (if known), shading area,
proposed equipment ratings, and insulation levels. The on-site test involves blower
door testing. Results of these tests, along with inputs derived from the plan review,
are entered into a computer simulation program to generate the HERS score and the
home’s estimated annual energy costs, based on heating, cooling, and hot water heating
requirements. Building America also recommends testing ducts for air leaks.
A HERS rating is an evaluation of the energy efficiency of a home, compared to a
computer-simulated reference house (of the identical size and shape as the rated home)
that meets minimum requirements of the International Energy Conservation Code
(IECC). More information on the code can be found at www.energycodes.gov. The
HERS rating results in a score between 0 and 100, with the reference home assigned a
score of 80. From the 80-point level, each 1 point increase in the HERS score results
in a 5 percent reduction in heating, cooling, and hot water energy usage (compared to
the reference house). An ENERGY STAR qualified new home, which is required to
be 30% more efficient, must attain a HERS score of at least 86. However, ENERGY
STAR criteria are currently under revision.
HERS RATER
Building America recommends
working with a HERS rater or
building scientist early in the
design process.
“We are building a much higher
performing home today than
we were building three years
ago based on what we learned
from the first Huntington
plan. You can see it in the
HERS ratings we receive
on our homes…it continues
to improve every day,” Jeff
Simon, executive vice president
of operations for Veridian
Homes.”
Jeff Simon, Executive Vice
President of Operations for
Veridian Homes
Your HERS rater can be a tremendous resource in the design phase. Raters who are
trained in building science may help to solve construction problems. One important
job your rater can help with is to work with the mechanical contractor to correctly
size heating/cooling equipment, perform room-by-room calculations to determine the
supply air needed for each room, and work with the mechanical contractor on duct
sizes and lay out. This is likely to eliminate callbacks due to comfort complaints and
can save substantial money by right-sizing the heating and cooling equipment. During
the design stage, the rater can suggest alternatives to attain desired performance levels in
the areas of energy, comfort, durability, and health.
Selecting a HERS rater is much like selecting any other professional services provider,
such as an architect, accountant, or engineer. Be sure you are comfortable with the
rater’s communication skills, experience, training, and references before making
a selection.
Best Practice: Building America recommends that every house receive a site inspection
and diagnostic tests from a HERS rating professional. The information gained from
these tests can help to isolate specific problem areas that can be solved with further
training, more explicit details, better building materials, or other production changes.
Building America Best Practices Series: Volume 4 – Builders and Buyers Handbook for
Improving New Home Efficiency, Comfort, and Durability in the Mixed-Humid Climate
SITE INSPECTION
Building America recommends that
every house receive site inspections
and diagnostic tests.
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Designers
Mixed-Humid
The mixed humid climate touches on four other climate zones, hot-humid, hot-dry,
mixed-hot, and cold. The mixed-humid climate has moderate conditions much of the
time. But weather conditions similar to those found in neighboring climate zones are
also frequent. Homes in the mixed-humid climate are faced with a substantial heating
season with monthly average outdoor temperatures dropping below 45ºF. And the
humid summers can have soaring temperatures.
FIGURE 2:
MIXED-HUMID
CLIMATE
During the winter heating season, vapor may be driven from the building interior into
the walls, roof, and floors. But in summer, air conditioning can force the house to turn
inside out. In summer, vapor may flow in the opposite direction as compared to winter,
with cold, dry air on the inside, and hot, moist air from the outside pushing its way in.
Houses in the mixed-humid climate cannot be built as if they are one-way streets for
moisture transfer.
Another set of challenges arises from the common use of full basements and
crawlspaces. These design features may bring extra living and storage space, but they
also bring their own moisture and temperature management challenges.
The recommendations in this Best Practices guide apply to the mixed-humid climate
region. If you aren’t sure that your project is within these climate regions, check
Appendix IV to see a listing of counties and their climate zones, or work with a HERS
rater to confirm your zone.
Design Best Practices for the Mixed Humid Climate
The mixed-humid climate stretched from New York City to Oklahoma and from the
Mid-Atlantic to the Midwest. Housing types vary greatly throughout this climate. In
the face of this diversity, this document does not recommend a single set of measures
for achieving the 30% energy savings in space conditioning, water heating, and
reaching ENERGY STAR qualification. We do recommend following the principles
included in these Best Practices and adjusting these practices and your designs to make
them work together. We also recommend working with a building scientist such as a
Home Energy Rating Professional to help with the transition.
The best practices described in this manual are intended to give builders and designers
recommendations resulting from Building America’s work on over 25,000 homes.
Building scientists have tried and tested these measures on actual homes in the field.
This does not mean that every measure will be for you. However, as builders start
aiming for higher performing homes, details become more important. It may not make
sense to install the best practice in every instance. Sometimes you can get away with
less. But making this decision should involve an evaluation of the risks of not using the
best practice, and questioning how the overall house system may be impacted.
Site – Drainage, Pest Control, and Landscaping
Additional planning information related to overall site development is presented in the
Site Planners
chapter.
Building America Best Practices Series: Volume 4 – Builders and Buyers Handbook for
Improving New Home Efficiency, Comfort, and Durability in the Mixed-Humid Climate
Version 1, 9/2005 • DES-5
Designers
Drainage
Moving moisture away from a building is critically important to maintaining structural integrity.
Best Practice: Grading and landscaping should be planned for movement of building
run-off away from the home and its foundation, with roof drainage directed at least 3
feet beyond the building, and a surface grade of at least 5% maintained for at least 10
feet around and away from the entire structure. This topic is also discussed in the Site
Planners
chapter.
FIGURE 3: Drainage
Drain Building
Drain Roof
Drain Wall
Drain Materials
Drain Components
Drain Openings
Drain Site
Drain Ground
Drain Site
GRADING
Plan grading and landscaping to
direct run-off away from the home
and its foundation.
“Now when we do new
product development—like
introducing new floor
plans—we are a lot more
particular on roof design and
how we are going to manage
the water, and this is a
direct tribute to Building
America. Before if we had
a house with a dead valley,
we would just field engineer
something and build around
it. Now, we just don’t accept
that from our architects.”
Vernon McKown,
Ideal Homes in Oklahoma
Drain Ground
Pest Control
Termites are a serious menace across the United States.
Best Practice: Based on local code and Termite Infestation Probability (TIP) maps,
use environmentally appropriate termite treatments, bait systems, and treated building
materials for assemblies that are near soil or have ground contact (check with County
Cooperative Extension Programs in the area you are building).
TERMITES
Use environmentally appropriate
termite treatments.
Landscaping
Landscaping is a critical element to the marketability of a house. But plants must be
placed to avoid interfering with visual inspections of termite access. Planting can also
be used to shade foundations and reduce cooling loads.
Best Practice: Plantings should be held back as much as 3 feet and no less than
18 inches from the finished structure, with any supporting irrigation directed away
from the finished structure. Plantings may be selected to shade the foundation edge,
especially on the southwest corner of the structure. Choosing native plantings results
in less irrigation and less chance for irrigation water to create a moisture problem
in the house. Decorative ground cover—mulch or pea stone, for example—should
be thinned to no more than 2 inches for the first 18 inches from the finished
structure. More landscaping information can be found on DOE’s Web site at
www.eere.energy.gov/consumerinfo/factsheets/landscape.html.
Building America Best Practices Series: Volume 4 – Builders and Buyers Handbook for
Improving New Home Efficiency, Comfort, and Durability in the Mixed-Humid Climate
PLANTINGS
Select indigenous plantings
and keep them at least 18 inches
from the foundation.
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Designers
Foundation System Moisture and Soil Gas Control
Slabs, crawlspaces, and basements are all found in the mixed-humid climate. All
building foundations should be designed and constructed to prevent the entry of
moisture and other soil gases.
Most foundation water leakage or intrusion is due to either bulk moisture leaks or
capillary action. Bulk moisture is the flow of water through holes and cracks. Capillary
action occurs when water wicks into the cracks and open spaces of porous building
materials, such as masonry block, concrete, or wood. These tiny cracks and pores can
absorb water in any direction, even going upward. Moisture can also be carried by soil
gas into homes.
Moisture may cause structural decay and can contribute to human health and comfort
problems. Radon that enters a home exposes occupants and may cause lung cancer.
The following practices apply to all foundation systems.
• Keep all untreated wood materials away from contact with earth and concrete.
• Design the house structure with overhangs, gutters, drainage planes, and
flashing to shed rainwater and conduct it away from the house.
• Slope the earth away from the house and ensure that no irrigation strikes near
the foundation as described in the Drainage section.
• Use a sill gasket for air sealing
• Install a protective shield such as metal flashing, plastic L bracket, or a
membrane to block capillary water wicking into the wall from the foundation.
This material can serve as a termite shield.
• Exterior foundation wall insulation requires a protective coating at abovegrade applications. Examples of protective coverings for exterior, abovegrade insulation include: flashing, fiber-cement board, parging (stucco type
material), treated plywood, or membrane material (EPDM* flexible roofing).
• Damp-proof all below grade portions of the exterior foundation wall to hinder
the absorption of ground water.
* EPDM stands for Ethylene
Propylene Diene Monomer.
• Place a continuous drainage plane over the damp proofing or exterior insulation
on foundation walls to channel water to the foundation drain and relieve
hydrostatic pressure. Drainage plane materials include special mats, high-density
fiberglass insulation products, and washed gravel. All drainage planes should be
protected with a filter fabric to prevent dirt from clogging the drainage channels.
Basements requires a foundation drain installed directly below the drainage plane and
beside (not on top of) the footing. Foundation drains are needed for crawlspaces and
slabs where the slab or the floor of the crawlspace is located below grade.
Slabs and Basement Floors
Best Practice: Slab foundations and basement floor require 6-ml polyethylene sheeting
or rigid foam insulation acceptable for below grade use directly beneath the concrete
that accomplishes vapor control and capillary control for the slab. The vapor retarder
should continuously wrap the slab as well as the grade beam.
Building America Best Practices Series: Volume 4 – Builders and Buyers Handbook for
Improving New Home Efficiency, Comfort, and Durability in the Mixed-Humid Climate
VAPOR CONTROL
Achieve vapor and capillary control
with sheeting or rigid insulation
directly below the slab.
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Designers
Best Practice: A sand layer under the slab or basement floor should never be placed
between a vapor retarder and a concrete slab. Cast the concrete directly on top of the
vapor barrier. Differential drying and cracking is better handled with a low water-to
concrete ratio and wetted burlap covering during initial curing.
Best Practice: Slab and basement floor drainage should include a gravel capillary break
directly beneath the slab vapor retarder.
Crawlspace Foundation Systems
Best Practice: In crawlspaces, install 6-mil polyethylene across the entire ground
surface. Overlay and tape all seams by 12 inches. Seal the polyethylene at least 6 inches
up the walls or to a height equal to ground level. Pressure treated wood strapping could
be used to fasten the polyethylene to the wall.
CASTING CONCRETE
Cast the concrete directly on top
of the vapor retarder, with no sand
in between.
DRAINAGE
Place a gravel capillary break
directly beneath the slab vapor
barrier.
CRAWLSPACE INSULATION
Thoroughly insulate and seal
all crawlspaces.
Some Building America teams make the following recommendations: install a
polyethylene groundcover at the beginning of construction, then install another one
on top of the first one when the crawlspace is ready to be sealed up to cover all rips and
holes. To improve durability, some Building America teams recommend pouring a
minimum 2-inch concrete slab over the polyethylene.
Best Practice: Moisture problems are best avoided by building non-vented crawlspaces.
Non-vented systems are described more fully in the Structure Thermal Performance
section. One source of moisture problems in crawlspaces comes from the combination
of moist air and cold temperatures. Air in crawlspaces may be moist due to the
proximity of soil and air leaks from the house. In humid summers, moisture is carried
into the crawlspace in the air drawn through traditional wall vents. When this warm
moist air reaches cooler structural framing, the moisture condenses out and can cause
mold and structural problems. In winter, cold air is drawn into the crawlspace and does
little to dry out crawlspaces, but can lower temperatures, cause condensation and freeze
exposed waterpipes. A non-vented crawlspace is a more hospitable environment for the
air distribution system to operate in.
NON-VENTED CRAWLSPACES
Moisture problems are best
avoided by building non-vented
crawlspaces.
Radon Control
In addition to other benefits, the gravel and vapor barriers under slabs, basement floors,
and crawlspaces are important first steps to radon control. The gravel provides a path
for radon and other soil gas to escape to the atmosphere rather than being drawn into
the house. And the vapor retarder helps to block soil gas entry into the house. Where
gravel is scarce, builders often pour slabs onto sand. When sand or other native fill is
used, a 3- or 4-inch perforated and corrugated pipe loop can be use for both drainage
and radon control. Or drainage matting may be installed over sand. Both approaches
are described in a U.S. Environmental Protection Agency (EPA) document.
Radon-resistant construction practices are described in the following documents for a
variety of foundation systems:
•
ASTM WK2469 New Standard (Formerly E1465-92)(draft) Guide for Radon Control
Options for the Design and Construction of New Low-Rise Residential Buildings
•
Model Standards and Techniques for Control of Radon in New Residential Buildings
(U.S. EPA 1994)
•
Building Radon Out: A Step-by-Step Guide on How to Build Radon-Resistant Homes (U.S. EPA
2001) available on the Web at www.epa.gov/199/iaq/radon/images/buildradonout.pdf.
Building America Best Practices Series: Volume 4 – Builders and Buyers Handbook for
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Version 1, 9/2005 • DES-8
Rigid insulation
Polyethylene or damp
proofing capillary break
Designers
Damp proofing
Rigid insulation
Perforated drainage
pipe embedded in
coarse gravel
Damp proofing
Continuous
polyethylene
Concrete footing
below frost depth
FIGURE 4: Typical Building Foundation Systems
EXTERIOR CRAWLSPACE INSULATION
Polyethylene or
damp proofing
capillary break
EXTERIOR BASEMENT INSULATION
= Sealant or Gasket
Radon reduction
3” plastic vent pipe
Rigid insulation
Rigid Insulation
Sill gasket membrane
Sill gasket membraneTreated
wood nailer
Cavity insulation
(also serves as capillary break)
Cavity insulation
(also serves as capillary break)
Metal termite flashing
Damp proofing
Metal
termite flashing
Continuous
polyethylene
Cover insulation
exposed above grade
Cover insulation
exposed above grade
Polyethylene or
damp proofing
capillary break
Treated wood nailer
(bring vapor barrier
up to grade level)
Rigid fiberglass insulation
Rigid fiberglass insulation
Polyethylene vapor barrier
Cavity
insulation
Damp proofing
Rigid insulation
Polyethylene or damp
proofing capillary break
Damp proofing
Perforated drainage
pipe embedded in
Damp proofing
coarse gravel
Perforated drainage
pipe embedded in
coarse gravel
Continuous
polyethylene
Concrete
Use extruded (R-5 per inch)
Sill gasket membrane
or expanded (R-4 per
inch)insulation
Cavity
(also serves as capillary break)
Perforated
drain pipe
Polyethylene or damp
proofing capillary Break
Seal all slab
penetrations
Concrete
slab
polystyrene or rigid
fiberglass insulation
Gravel base
Damp proofing
Perforated drainage
pipe embedded
in gravel
footing
depth
Radon reduction
3" plastic pipe vent stack
Hold drywall
1/2” above floor
3”reverse)
plastic vent pipe
(see list on
Rigid fiberglass insulation
Rigid insulation
with foil facing
below frost
Polyethylene
or
damp proofing
capillary break
Cover insulation
exposed aboveRadon
gradereduction
Cover insulation
exposed above grade
Damp proofing
Polyethylene or
damp proofing
capillary break
Rigid insulation
Concrete footing
below frost depth
Metal termite flashing
Polyethylene vapor
diffusion retarder
Polyethylene or damp
proofing capillary Break
(4-6" deep coarse, no fines) Cavity
insulation
Polyethylene vapor diffusion retarder
Polyethylene or damp proofing capillary break
Damp proofing
Polyethylene
vapor
EXTERIOR
INSULATION
diffusion retarder
PACKAGE
Concrete footing below frost depth
Damp proofing
Polyethylene or
damp proofing
capillary break
Rigid insulation
with foil facing
= Sealant or Gasket
Perforated drainage
pipe embedded
in
Best
Practice
: Other than identifying areas that have had radon problems, it is not
coarse gravel
possible to predictConcrete
radon
levels in houses prior to construction, so it is important to
footing
below frost depth
include inexpensive radon control measures. One measure recommended by the EPA
to control potentially high radon levels and other soil gasses, is a passive soil gas stack
connected to a perforated drain pipe embedded in the gravel under the slab, basement
floor, or crawlspace ground cover. The stack may also be attached to a perforated pipe
loop or mat. If it turns out the house has unacceptable radon levels, a fan can be added
to the stack to actively draw soil gas away from the house. To determine potential
radon levels in the county in which you are building, visit the EPA’s radon potential
map at www.epa.gov/radon/zonemap.html.
RADON
Houses built in areas with
potentially high radon levels can
install a soil gas stack to draw soil
gas away from the home.
For information about local variation in radon levels you can find local contacts at
the following EPA Web site: www.epa.gov/iaq/whereyoulive.html. The EPA divides
counties into one of three zones based on radon level potential. The EPA recommends
that all homes built in Zone 1 (high radon potential) areas have radon reduction systems.
Structural Moisture Control
Moisture is a significant problem in this climate in the form of both high humidity and
high rainfall. Most of the mixed humid climate receives more than 40 inches of annual
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precipitation. Some areas get more than 60 inches of annual precipitation. The ambient
air has significant levels of moisture most of the year. Since air conditioning is installed
in most new homes, cold surfaces are present where condensation can occur. Controlling
the infiltration of this moisture-laden air into the building envelope and keeping moisture
away from cold surfaces are major goals of design and construction in this climate zone.
Two types of rain management systems have been identified: barriers and screens. Barriers
rely on exterior cladding to drain water and are best used with water-resistant building
materials, such as masonry block or concrete. Screens have multiple lines of defense
against water entry and are used with wood, brick, and gypsum-based materials. Both
barriers and screens rely on lapped flashings to direct water to the exterior at critical areas
such as seams, windows, and penetrations. In both systems, it is essential that materials
are lapped shingle fashion to direct water down and out, away from the wall assembly.
Best Practice: Roof and wall assemblies must contain surfaces that will drain water in
a continuous manner over the entire area of the building. Water must have a path that
will take it from its point of impact, around any elements such as windows, doors, and
seams, all the way to the exterior ground, sloping away from the house.
Best Practice: In areas with potentially high winds and heavy rains install four-inch to
six-inch “peel and seal” self-adhering water-proofing strips over joints in roof decking
before installing the roof underlayment and cover.
Best Practice: Carefully install insulation and air barriers to avoid ice dams.
Ice dams may be a problem in colder portions of the mixed-humid climate. When
roof snow melt refreezes it can build up ice that blocks water flow. Newly melted snow
adds to the ice dam and eventually can cause water to back up under shingles and
flashing and can cause safety hazards with suddenly released snow and ice. Snow could
be melted by warm air leaking from the house into the attic. The control of outwardly
leaking air is the most effective means of stopping ice dams. This can be accomplished
by the installation of air barriers at the ceiling (see the section on Structural Air
Sealing). Well insulated roof areas also help to keep the surface of the roof cool to avoid
the melt-freeze cycle (see the section on Structural Thermal Performance).
Water Leakage
Some snowmelt in unavoidable and in transitional weather, rain may temporarily back up
behind ice dams. To minimize leakage, install roof membranes in roof valleys and at eaves.
One critical point of concern is water leakage around windows. The EEBA Water
Management Guide offers examples of many window flashing applications. The window
flashing examples here are taken from the Trades
chapter. These examples are for
homes with housewrap and plywood or OSB sheathing.
Best Practice: Specify that flashing be installed for all windows and doors. Window and
VAPOR BARRIERS
Roof and wall assemblies must
contain elements that, individually
and in combination, permit drying
of spaces inside of walls.
WATER-PROOFING
ROOF DECKING
Install water-proofing strips over
joints in roof decking.
PREVENT ICE DAMS
Carefully install insulation and air
barriers to avoid ice dams.
“I think the number one issue
facing home owners is moisture
management. Construction
detailing around windows and
doors is something that the
building industry doesn’t truly
understand. You know, no
where in the building code do
they inspect for flashing.”
Vernon McKown, the co-owner of
Ideal Homes in Oklahoma, which
builds all its homes using Building
America principles.
WINDOW FLASHING
Flashing should be installed
for all windows.
FIGURE 5:
Window Flashing Building Tips
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OU
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door flashing details should be designed to match specific wall assemblies and claddings.
Flashing systems should be designed in accordance with the ASTM standard entitled
Standard Practice for Installation of Exterior Windows, Doors, and Skylights (ASTM
2002). In addition to the standard and the EEBA guide, see DOE’s Technology
Fact Sheet on Weather-Resistive Barriers (DOE 2000), available on the Web at
www.eere.energy.gov/buildings/documents/pdfs/28600.pdf.
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CA
HO
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Complete instructions for window
flashing are provided in the Trades
chapter of this handbook.
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Extreme Weather
Parts of the mixed-humid climate can be vulnerable to catastrophic high wind, heavy
snow falls, and heavy-rain events, such as severe thunderstorms, tornados, and hurricanes.
Proper structural fastening and impact resistant windows, doors, and skylights are critical
to surviving high winds. Proper use of roofing materials can help roofs withstand snow
loads and high winds, and protect against severe rains. This document does not provide
detailed information on disaster survival but the following sources provide structural
details and guidance and a listing of building materials acceptable for high wind areas.
• Federal Emergency Management Agency. Building a Safe Room Inside
Your Home. www.fema.gov
• Federal Alliance for Safe Homes – FLASH, Inc. Designed primarily for Florida,
this Web site contains generally-applicable information about building to resist
high winds, wild fires, and floods. Blueprint for Safety. www.blueprintforsafety.org
“Building America gave us a
lot of construction detailing on
flashing, draining, and water
management which builders
in Oklahoma here do not
understand.”
Vernon McKown, the co-owner of
Ideal Homes in Oklahoma
• Institute for Business and Home Safety. The IBHS has building guidelines and
public information. www.ibhs.org
• U.S. Department of Energy. A training program for home inspectors to
identify hazards. www.eere.energy.gov/weatherization/hazard_workshop.html
Vapor Management
Water has many guises and water in its liquid state is not the only problem. Water can also
cause problems as vapor. The problem is especially bad when vapor gets trapped within an
assembly, such as a wall; turns to its liquid form (condenses); and wets structural assemblies.
Condensation can also form in and on ductwork, especially when air conditioning cools
duct surfaces that come in contact with humid air, such as in a vented attic or crawlspace.
The recommendations below are intended to help control both liquid water and vapor.
In mixed climates, building assemblies need to be protected from getting wet from
both the interior and exterior and to be allowed to dry to either the exterior or interior.
There are three general strategies (Lstiburek 2001):
• Installing vapor diffusion retarders on the interior and exterior of wall
assemblies to block moisture entry from both directions. This approach could
be very dangerous if moisture is trapped inside the wall.
• Allowing vapor to “flow through” by using permeable building materials on
both interior and exterior sides of the building assemblies. This allows water
vapor to diffuse through the assembly from interior to exterior during heating
periods and from exterior to interior during cooling periods.
• Putting the vapor diffusion retarder roughly in the “middle” of the assembly by
installing impermeable or semi-permeable insulating sheathing on the exterior
of a frame cavity wall that is filled with permeable insulation.
The second option is least costly and is adequate for achieving the modest energy
efficiency targets of this best practices handbook.
Best Practice: Do not install impermeable coverings, such as vinyl wallpaper, on exterior walls
and do not install polyethylene vapor retarders on the framing side of gypsum board or other
wall coverings. Painted drywall should protect against moisture movement from the inside.
Best Practice: Roof and wall assemblies must contain elements that, individually and
IMPERMEABLE COVERINGS
Impermeable coverings inside the
house are not recommended.
HOUSEWRAPS
Install exterior housewraps.
in combination, permit drying of spaces inside of walls and other assemblies. Exterior
Building America Best Practices Series: Volume 4 – Builders and Buyers Handbook for
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housewraps, including building paper, will allow vapor to pass through and should be
installed on the exterior of sheathing.
Best Practice: Water soaking through wood can carry with it contaminants that
BACKPRIMING
interfere with the ability of housewraps and building papers and felts to resist water.
One step in the solution is to backprime all wood cladding to avoid water saturation
and migration. This practice also makes the wood much more durable.
Backprime all wood cladding
to avoid water saturation.
Best Practice: Creating an air space between the cladding and the drainage plane
AIR SPACE
effectively increases the durability of both components. With some exterior
finishes, such as bricks, an air space is even more important. An air space stops
the capillary movement of moisture, stops the contamination of the drainage
plane via contact with the cladding, and allows for better drying. Information on
housewrap and building paper performance behind brick and stucco can be found at
www.buildingscience.com/resources/walls/brick_stucco_housewraps.pdf
Creating an air space between
the exterior finish and the drainage
plane effectively increases the
durability of both components.
Best Practice: If building paper or felt is used in areas prone to severe rain, install half-
TWO LAYERS OF
BUILDING PAPER OR FELT
lapped felt, which effectively creates two layers. By providing a double drainage plane,
the two layers offer increased resistance to leakage at fasteners and allow for more
flexible installation.
Consider installing two layers
of building paper or felt to create
a double drainage plane.
Best Practice: Installation is key for all types of housewraps. The sheets must be lapped,
shingle-style, especially over and around windows, doors, and other penetrations (and
their flashing systems). Use manufacturer-specified fasteners and space them closely
enough to provide required support.
Additional information on moisture control, crawlspace insulation, basement
insulation, and slab insulation can be obtained from:
CAREFUL INSTALLATION
Pay close attention to lapping,
especially around windows and
doors, as well as the proper use
of fasteners.
• Lstiburek, Joseph. 2003. EEBA Water Management Guide (Lstiburek
2003), available for sale from the EEBA Bookstore, on the Web at
www.eeba.org/bookstore.
• DOE’s Technology Fact Sheets on Weather-Resistive Barriers, available on
the Web at www.eere.energy.gov/buildings/info/
• Building Science Consortium’s Web site at www.buildingscience.com/
housesthatwork/buildingmaterials where you can compare wraps and
other materials.
• www.buildingscience.com/resources/walls/problems_with_housewraps.htm
• The following article provides an overview of house wraps and was a key
source for this section: Straube, John. 2001. “Wrapping it Up,“ Canadian
Architect. May, 2001. Available at www.cdnarchitect.com.
• The National Association of Home Builders Research Center’s
Moisture Protection of Wood Sheathing is available on the Web at
www.nahbrc.org/docs/mainnav/moistureandleaks/792_moisture.pdf.
• DOE’s Energy Savers fact sheet titled Vapor Diffusion Retarders and Air Barriers
available on line at: www.eere.energy.gov/consumerinfo/factsheets/bd4.html
• Lstiburek, Joseph. 2004. Builders Guide to Cold Climates. Available at
www.eeba.org/bookstore
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Improving New Home Efficiency, Comfort, and Durability in the Mixed-Humid Climate
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The Ins and Outs of Vapor
It’s been said that water is lazy, it will always follow the easiest path as it is pulled along
by gravity. However, moisture can also cause problems as vapor. Unlike moisture in its
liquid form, vapor travels where ever air flows. Air is vapor’s heavy lifter. Where there
are air leaks, there are vapor leaks.
Diffusion can also force vapor through materials and into places it shouldn’t be, such
as wall cavities. Differences in vapor pressure and temperature are the forces that drive
diffusion. Vapor diffusion moves moisture from areas of higher vapor pressure to areas of
lower vapor pressure, and from areas of greater temperature to areas of lesser temperature.
The most important point to make about these two types of vapor transport is that air
movement is by far the more important mechanism for moving vapor. Seal up air leaks
in the building envelope, both inside and out, and most vapor transport will be blocked
from getting inside structural cavities.
The installation of air barriers involves systematically and continuously sealing air leaks.
Methods for creating air barriers are described in the section on structural air sealing.
Continuous means that the barrier extends over the entire surface of the structure, but
the barrier may be made up of many materials. The interior gypsum board may be
incorporated into the air barrier, along with studs, draft stopping materials, housewraps,
and rigid insulation, as long as the seal is continuous.
Vapor diffusion retarders are materials that block diffusion because they are
impermeable. A perm is a unit of measurement based on the amount of water that
passes through a material over a fixed period of time. Four classes of permeability have
been established. Here are the classes along with examples of materials (adapted from
Lstiburek 2004):
•
Vapor impermeable (0.1 perm or less): polyethylene film, glass,
aluminum foil, sheet metal, foil-faced rigid insulation, and other
foil-faced materials.
•
Vapor semi-impermeable (1.0 perm or less and greater than 0.1 perm)
oil-based paints, most vinyl wall coverings, unfaced extruded polystyrene
greater than 1 inch thick, kraft-faced fiberglass insulation.
•
Vapor semi-permeable (10 perms or less and greater than 1.0 perm):
plywood, bitumen impregnated kraft paper, oriented strand board,
unfaced expanded polystyrene, unfaced extruded polystyrene (1-inch
thick or less), building paper, and most latex paint.
•
Vapor permeable (greater than 10 perms): unpainted gypsum board and
plaster, unfaced fiberglass insulation, cellulose insulation, dimensional
lumber, and masonry.
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Designers
Housewrap, Building Paper, or Felt – Your Choices for Wrapping it Up
Housewrap, building paper, or impregnated felt should be part of the exterior wall system
that protects the building from water penetration. None of the materials are waterproof,
but are intended to shed rainwater that penetrates exterior cladding. The surface formed
by these materials is called a drainage plane, house membrane, or rain barrier. They are
used to shed liquid water that may penetrate siding or roofing and to prevent liquid water
from wicking through them, while remaining sufficiently vapor permeable (“breathable”)
for outward drying (Straube 2001). By helping to keep building materials dry, these
membranes improve building durability, decrease maintenance costs, and reduce the risk
of moisture-related problems such as pests, mold, and rot.
Building Paper is a Kraft paper sheet impregnated with asphalt to increase its strength
and resistance to water penetration. It is primarily employed as a drainage layer. It is
graded according to a test of the amount of time required for a water-sensitive chemical to
change color when a boat-shaped sample is floated on water. Common grades include 10,
20, 30, and 60 minutes. The larger the number, the more resistant the paper is to water.
Building Felts have been in use over a hundred years. Originally made from rags, today’s
felts are made of recycled paper products and sawdust. The base felt is impregnated with
asphalt. Ratings for felt harken back to the traditional weight of the material before the oil
crisis of the 1970s. At that time 100 square feet of the material (1 square) weighed about
15 pounds. Modern #15 felt can weigh from 7.5 to 12.5 pounds per square depending on
the manufacturer.
Housewrap typically refers to specially designed plastic sheet materials. Housewrap
comes in a variety of materials and can be perforated or non-perforated. If joints and
connections are sealed, housewraps can serve as air retarders to reduce air leakage.
Housewraps are highly resistant to tearing, unlike building paper. Non-perforated wraps
tend to have higher liquid water resistance because the holes between plastic fibers are
very small.
Most building paper is UV-resistant, whereas recommended housewrap exposure limits
may vary by manufacturer. Check with manufacturers if outdoor exposure will exceed
a month. One person can usually install building paper, while housewrap requires two
people. However, housewrap is available in wide sheets that can cover an entire one-story
wall surface in a single pass.
Adapted from Straube 2001.
Structural Air Sealing
Best Practice: Use either interior gypsum board, exterior sheathing, or both as a
continuous air flow retarder. Exterior stucco may also serve as an air flow retarder.
Carefully seal big and little holes. Pay particular attention to sealing shared walls and
attic spaces between garages and houses.
Best Practice: Use sheet goods, such as hard board, rigid foam insulation, polyethylene
sheet plastic, plywood, or sheet metal to seal holes behind tubs, shower stalls, stairs
fireplaces, and other potential bypasses.
Building America Best Practices Series: Volume 4 – Builders and Buyers Handbook for
Improving New Home Efficiency, Comfort, and Durability in the Mixed-Humid Climate
AIR SEALING
Be sure to seal shared walls and
attic spaces between garages
and houses.
SHEET GOODS
Use sheet goods to seal holes
behind all potential bypasses.
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Designers
FIGURE 6: Envelope Air Sealing
ENERGY STAR THERMAL
BYPASS CHECKLIST
The checklist stipulates 13 areas
that require special attention to
insulation and air barrier continuity.
1) Exterior walls behind tubs
and showers
2) Floors over garages
3) Attic knee walls
4) Attic hatch opennings
and drop down stairs
5) Cantilevered floors
6) Duct shafts
7) Flue Shafts
8) Piping shafts and penetrations
9) Dropped ceilings and soffits
10) Fireplace walls
11) Staircase framing on
exterior walls
Source: Building Science Corporation
A tight building envelope is necessary to control the movement of air in and out of
building assemblies. Air infiltration can contribute to problems with moisture, noise,
dust, and the entry of pollutants, insects, and rodents. Using mechanical ventilation as
a superior approach to supplying fresh air is discussed in the section on Mechanicals,
Electrical, and Plumbing.
Moisture-laden air moving into wall or roof assemblies may lead to condensation and
result in deterioration of moisture sensitive materials. Airflow retarders can be installed
on the interior or the exterior side of the envelope or on both sides. Insulation made
up of batt or loose fill products does not seal against air leakage. Rigid foam board
insulation can be used as both a moisture and air retarder.
Controlling air movement through the building envelope requires sealing both the
“big” holes and the “little” holes. The big holes occur behind bathtubs and showers
on exterior walls, behind fireplaces, and where soffits or utility walls (double wall with
chase) meet exterior walls or ceilings. Recessed lights collectively can be a really big hole
in the ceiling assembly. These big holes are responsible for wasted energy (high utility
bills) and condensation that can cause mold and wood decay. These holes are easy to
seal during the framing stage but only when someone has the responsibility for making
sure it gets done. Only airtight recessed lights (ICAT-rated) should be used in ceilings
leading to unconditioned spaces.
12) Recessed lighting
13) Whole-house fan penetrations
“Air stoppage is the biggest
thing you can do and one
of the cheapest.”
Michelle Horstemeyer, a lead
builder for John Wieland Homes
The little holes occur between framing members (such as band joist to sill plate),
around electrical boxes, and where plumbing or wiring penetrate the envelope. All
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penetrations leading to unconditioned spaces should be sealed with foam or caulk. See
the Trades
chapter, Building Tips on air sealants and the instructions for plumbers,
electricians, and framers. Also see the sections later in this chapter for plumbing and electrical.
INTERSECTIONS OF
WALLS & ROOF
When air sealing drywall, gypsum board acts as an interior air flow retarder. The
gypsum board is sealed to the framing members at the perimeter of exterior walls and
around penetrations such as doors, windows, and attic hatches. The gypsum board is
also sealed to electrical boxes on exterior walls. Air cannot move through the gypsum
board and the taped corners.
FIGURE 7 & 8: Knee Walls
Tight sealing of the intersection
of the roof and wall may require
blown-in foam.
Figures 7 and 8 show possible
approaches to sealing knee walls.
There are many approaches and practices to sealing buildings. Many details and
photographs of air sealing techniques can be found on the Building Science
Corporation Web site at www.buildingscience.com/housesthatwork/airsealing.htm,
in the EEBA Builders Guides, and in the DOE Technology Fact Sheet on Air Sealing
available on the Web at www.eere.energy.gov/buildings/documents/pdfs/26448.pdf.
Best Practice: One area to pay attention to for sealing is the intersection of the walls
and roof. This area may involve an attic, cathedral ceiling, knee walls, all of the above,
or other examples of complex roof lines. Figures 7 and 8 show knee wall examples.
Tight sealing of this intersection may require blown-in foam. Careful work in these
areas will help avoid ice dams.
Best Practice: Another area needing special attention for occupant health and safety is
Desired
ventilation
Use rigid foam or sheet goods
to seal joist cavities
Seal knee wall to create a
continuous air barrier. Knee walls
can be sealed following the wall
and attic floor.
sealing shared walls and ceilings between attached garages and living spaces. Carefully
seal any penetrations, block air pathways through the attic, and weatherstrip any doors.
Structural Thermal Performance
Seal
Hardboard
Properly installed insulation is like your favorite winter comforter for keeping heat where it’s
wanted. Any interior insulation type is acceptable that has vapor permeability. These include
cellulose, fiberglass, and foam. Foam can also serve as an air retarder, but air sealing must be
accomplished by a separate component or system when cellulose or fiberglass is used.
How Much Insulation Do You Need?
This is an excellent question to ask your Home Energy Rater. The answer depends on your
location, the overall design, and the efficiency of other building features. Using a systems
approach, insulation can be traded off with other building features. The ENERGY STAR
Web site contains Builder Option Packages (BOPS) that recommend insulation levels on
a county by county basis. The BOPS can be found at www.energystar.gov. Examining the
ENERGY STAR BOPs provides some examples of how insulation can be traded off with
other features such as efficient windows and HVAC systems. DOE can also help with in
sulation recommendations for each zip code. Visit the Web site below. Have in hand the
first three digits of your zip code, the type of heating system that you are considering, and
local energy costs for electricity or natural gas. The calculator will recommend an insulation
level: www.ornl.gov/sci/roofs+walls/insulation/ins_16.html
If you prefer to work with a map, the following DOE Web site will give you recommended
insulation levels:www.eere.energy.gov/consumerinfo/energy_savers/r-value_map.html
These recommendations are only guidelines and are limited in scope. The more complex or
advanced your design, the more you should rely on specific calculations.
Building America Best Practices Series: Volume 4 – Builders and Buyers Handbook for
Improving New Home Efficiency, Comfort, and Durability in the Mixed-Humid Climate
Seal
In new homes, it is preferred
to seal along the sloping edge
of the attic roof.
SHARED WALLS & CEILINGS
WITH GARAGES
Pay special attention to the shared
walls and ceilings between attached
garages and living spaces.
“It proved to me that some of these
measures are worth the extra
money, for example, a radiant
barrier roof shielding—it helps
deflect the heat of the sun, and
this helps with the heating bills
in the summer time.”
Michelle Horstemeyer, a lead
builder for John Wieland Homes’
first Building America home the 2002
New American Home in Atlanta.
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Designers
The following descriptions of insulation were adapted from DOE’s Fact Sheet on
Insulation available on the Web at www.ornl.gov/sci/roofs+walls/insulation/ins_08.html.
Blankets
Blankets in the form of batts or rolls are flexible products made from mineral fibers,
typically fiberglass. They are available in widths suited to standard wall, floor, and
attic framing spaces. Continuous rolls can be hand-cut and trimmed to fit. They are
available with or without vapor retarder facings. High-density fiberglass batts are
about 15% more effective than traditional batts. Even if you choose to use other types
of insulation, such as blown or sprayed in cellulose or foam, batts can be installed in
areas that may become inaccessible as construction unfolds. These areas could include
behind-shower inserts, stairs, or rim joists. Batts also make good dams in attics around
access points or other areas where blown-in insulation should be held back.
INSULATION
Use high-density batts, when
fiberglass batt insulation
is specified.
FIGURE 9: Insulation
Best Practice: When fiberglass batt insulation is specified, use high-density, unfaced
or kraft-faced batts. Batt facing is a vapor retarder and can trap moisture inside walls.
Check local code requirements.
Blown-in wall insulation
Blown-In
Blown-in, loose-fill insulation includes loose fibers or fiber pellets that are blown into
building cavities or attics using special pneumatic equipment. Another form includes
fibers that are co-sprayed with moisture or an adhesive that allows them to set in
walls and makes them resistant to settling. The blown-in material can provide some
resistance to air infiltration if the insulation is sufficiently dense.
Foamed-In-Place
Foamed-in-place foam insulations can be applied by a professional applicator using
special equipment to meter, mix, and spray into cavities. Foam makes an excellent air
seal and can be used to reach hard-to-get-at places.
Rigid Insulation
Rigid insulation is made from fibrous materials or plastic foams that is pressed or
extruded into sheets and molded pipe-coverings. These provide thermal and acoustical
insulation, strength with low weight, and coverage with few heat loss paths. Such
boards may be faced with a reflective foil that reduces heat flow when next to an air
space. Foil facing also makes the board nearly impervious to water and vapor and so
should be used with caution. Rigid foam insulation may be used in combination with
other insulation types, such as on the exterior of walls that are filled with cellulose or
fiberglass. Foam sheets that may be in contact with the ground should be borate-treated
for termite resistance (see Figure 11 on page 22 for an example of rigid foam insulation).
Rigid insulation may also be applied to the interior and exterior of foundation walls.
Reflective Insulation Systems
Reflective insulation systems are fabricated from aluminum foils with a variety of
backings such as roof sheathing, craft paper, plastic film, polyethylene bubbles, or
cardboard. These systems are not recommended for the cold and very cold climates.
If a single reflective surface is used alone and faces an open space, such as an attic, it
is called a radiant barrier. Radiant barriers are not recommended for cold and very
cold climates.
Batt insulation
Reflective insulation
Spray-in foam insulation. Soy-based
foams are now available
(Photo: Building Science Corporation)
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Designers
Slab Foundation Insulation
Slabs in the mixed-humid climate may be insulated at the perimeter with borate-treated
foam board or rigid glass fiber insulation. Use only insulation approved for belowgrade use. Some code officials may require a gap between exterior insulation and wood
foundations elements to provide a termite inspection area. Exterior insulation should
be applied from the top of the foundation wall to the bottom of the frost line. Cover the
exterior face of the insulation exposed to outside air using material such as flashing, fiber
cement board, parging (stucco type material), treated plywood, or membrane material.
A shallow, frost protected slab foundation may be used in areas subject to seasonal
ground freezing. With this approach, foundation footings need not be placed below
frost depth. However, rigid insulation, approved for below-grade use, must be placed
vertically on the exterior of the grade beam, and must be placed to extend away from the
foundation horizontally at the base of the grade beam for a distance equivalent to frost
depth. Rigid insulation is also needed vertically on the inside of the grade beam, and
must extend horizontally under the slab, on top of the gravel capillary break, for two feet.
Code officials may require that a structural engineer review and approve specific plans.
For more information on shallow foundations see:
• Houses that Work (BSC 2004), www.bsc.com
• The American Society of Civil Engineers standard (number 32-01), Design and
Construction of Frost-Protected Shallow Foundations.
• University of Minnesota, Building Foundations Research
Program., Frost Protected Shallow Foundations Design Specifications.
www.buildingfoundation.umn.edu/MHFAfrostFoundation.htm
Slab perimeters may be insulated on the interior side. This approach requires that rigid
insulation be placed between the slab and the foundation wall, and under the slab, as
required by local code.
Crawlspace Insulation
Crawlspaces are a foundation method used in the mixed-humid climate. Two methods
are in use for insulating crawlspaces. The first, in common use over the last several
decades, is to insulate the underside of the building floor, and provide outside air
vents in foundation walls. Research has shown that this approach can lead to moisture
problems, especially in areas with cold or humid air.
Best Practice: A better approach is referred to as conditioned crawlspaces, or
mechanically vented crawlspaces. Within this type of system, foundation side walls are
insulated on either the interior or exterior (or both), and no outside air vents tunnel
through the foundation wall.
Building America Best Practices Series: Volume 4 – Builders and Buyers Handbook for
Improving New Home Efficiency, Comfort, and Durability in the Mixed-Humid Climate
CONDITIONED CRAWLSPACES
Insulate foundation side walls on
either the interior or exterior (or both).
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Designers
Best Practice: The preferred approach is to install insulation on the exterior foundation
wall. Exterior insulation will help to protect the foundation from the freeze-thaw
cycle and a warmer wall is less likely to condense moisture. Products such as boratetreated foam board or rigid glass fiber insulation work well. Extruded polystyrene
(R-5 per inch) is durable and moisture resistant. Expanded polystyrene (R-4 per inch)
is less expensive, but it has a lower insulating value. Rigid fiber glass insulation does
not insulate as well as foam but provides a drainage plane. Some code officials may
require a gap between exterior insulation and wood foundations elements to provide a
termite inspection area. Insulation that is exposed above grade must be covered with a
protective coating such as flashing, fiber cement board, parging (stucco type material),
treated plywood, or membrane material.
EXTERIOR INSULATION
Install insulation on the exterior
foundation wall to help protect
the foundation from the freezethaw cycle.
Fig 10. Conditioning Crawlspaces
(AHU: Air Handling Unit)
If placed on the interior, wall insulation must extend down the wall to a depth at
least 2 feet below grade level and be rated for crawlspace and basement exposure.
Polyisocyanurate insulation with an aluminum facing is a good interior insulation
choice. If the crawlspace wall extends less than 2 feet below grade level, then the
remaining insulation must be placed horizontally along the ground at the base of the
wall. A sealed ground cover is installed over the entire area of the crawlspace. Install a
system to provide conditioned air to the crawlspace. More information is available at:
• Building Energy Codes Resource Center, Details for Mechanically Vented
Crawlspaces - Code Notes, www.energycodes.gov/support/code_notes.stm
(includes information on sizing the mechanical ventilation).
A: Supply air to crawlspace
• University of Minnesota, Building Foundations Research Program. Minnesota
Energy Code Building Foundation Rule: Amendment Proposal Development
Project Final Report, www.buildingfoundation.umn.edu/FinalReportWWW/
Section-A/A-recs-main.htm
• www.crawlspaces.org This Web site is geared toward research done on
crawlspaces in the mixed-humid climate.
See these documents from Building America Consortia available at
www.buildingamerica.com in the Publications section.
B: Return air from crawlspace
• Broniek, John. Builder System Performance Packages Technical Report. Prepared
by IBACOS for the Building America Program.
• Yost, Nathan. May 2003. “The Case for Conditioned, Unvented
Crawlspaces.” Building Safety Journal. Also available on the BSC Web site at :
www.buildingscience.com/resources/articles/24-27_Yost_for_author.pdf
• IBACOS. 2002. Best Practices: Consider the Crawlspace.
C: Supply and return to crawlspace
For all configurations above:
• Minimum 2-4”x8” transfer grilles
from house
• 20 cfm of flow per 1,000ft2 of crawlspace
• Air handler cycled at 5 minutes per hour
Source: Building Science Consortium
Building America Best Practices Series: Volume 4 – Builders and Buyers Handbook for
Improving New Home Efficiency, Comfort, and Durability in the Mixed-Humid Climate
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Designers
Basement Insulation
Basements are a common foundation system in the mixed-humid climate. Wall
insulation in basements is similar to the approaches described for crawlspaces. And
basement floors are insulated in ways similar to slabs.
Best Practice: Exterior wall insulation is preferred over interior approaches (Broniek
2003; Yost and Lstiburek 2002). Exterior insulation will help to protect the basement
wall from freeze-thaw cycles and will help make the wall warmer, giving condensation
less chance of forming and improving thermal comfort. Exterior insulation’s position
outside of damp proofing makes it less likely to contribute to problems of trapped
moisture inside basement walls. Exterior wall insulation must be approved for belowgrade use. Products such as borate-treated foam board or rigid glass-fiber insulation work
well. Extruded polystyrene (R-5 per inch) is durable and moisture resistant. Expanded
polystyrene (R-4 per inch) is less expensive, but it has a lower insulating value. Rigid
fiber-glass insulation does not insulate as well as foam but it is the only insulation option
that provides a drainage plane for foundation walls. Some code officials may require a
gap between exterior insulation and wood foundations elements to provide a termite
inspection area. Insulation that is exposed above grade must be covered with a protective
coating such as flashing, fiber cement board, parging (stucco type material), treated
plywood, or membrane material. Exterior insulation is an especially good choice in areas
with high water tables or poor draining soils.
EXTERIOR BASEMENT
INSULATION
Install insulation on the exterior
foundation wall to help protect
the foundation from the freezethaw cycle.
If interior insulation is used it is important to consider moisture control, insulation
flame spread rating, and moisture compatibility. Yost and Lstiburek (2002) discuss
three requirements for interior basement insulation systems.
• It must dry to the interior if wetting occurs because the below-grade portion
of the wall cannot dry to the exterior. This requirement means that interior
polyethylene vapor barriers or any impermeable interior wall finishes such as
vinyl wall coverings or oil/alkyd/epoxy paint systems should not be installed.
• The wall system must be tightly sealed to keep interior air from reaching the
cool foundation wall. The system must have either an effective interior air
barrier (see the section on structural air sealing), or rigid insulation could be
installed directly on the interior concrete or masonry surfaces.
• Material is contact with the foundation wall and the concrete slab must be
moisture tolerant. A capillary break must be placed between materials that
transport moisture and moisture sensitive materials.
Yost and Lstiburek go on to present three strategies for interior basement insulation.
The first system uses foil-faced polyisocyanurate rigid insulation attached directly to the
upper portion of the basement wall. Extruded or expanded polystyrene can be attached
to the below-grade portion of the wall. The polystyrene would require a gypsum board
or equivalent covering. Extending gypsum board up the entire wall, leaving at least a
half-inch gap at the floor to avoid wetting, provides a finished wall.
A second system has either expanded or extruded polystyrene foam board attached
to the entire foundation wall. Extruded polystyrene is more moisture tolerant and
should be used if there are any doubts in the external drainage system. Additional
insulation can be added to a frame wall built on the interior of the foam insulation. If
no additional insulation is desired, wood furring strips can be attached over the foam
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Improving New Home Efficiency, Comfort, and Durability in the Mixed-Humid Climate
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Designers
and gypsum board attached to the furring strips. A similar approach is described in the
masonry wall section of this report, suggests the installation of 2x4 furring, against the
basement wall, at the intersection with the ceiling, if a firestop is required. Check with
local code officials about required fire ratings and stops. Gypsum board should be held
at least a half inch above the basement floor to avoid wetting.
A third approach uses pre-cast concrete foundation walls that come with a minimum of
1 inch of rigid foam insulation attached to the interior.
Broniek suggests that a blanket insulation with a perforated facing (to allow drying
of the wall to the inside) can also be used on the inside face, but it is best used in
combination with exterior insulation and in conditioned basements.
For more information on basement insulation see the following:
• Broniek, John. 2003. Builder System Performance Packages Technical Report.
Prepared by IBACOS for the Building America Program. Available at
www.buildingamerica.gov in the publications section.
• Yost, Nathan, and Joseph Lstiburek. 2002. Basement Insulation Systems.
Prepared by the Building Science Consortia for the Building America Program.
Available at www.buildingamerica.gov in the publication section.
• DOE, Office of Building Technology. 2002. Technology Fact Sheet: Basement
Insulation. Available at www.buildingamerica.com in the publication section.
• IBACOS. 2002. Don’t Forget About the Basement. Prepared by IBACOS for
the Building America Program. Available at www.buildingamerica.gov in the
publications section.
• University of Minnesota, Building Foundations Research Program. Minnesota
Energy Code Building Foundation Rule: Amendment Proposal Development
Project Final Report, www.buildingfoundation.umn.edu/FinalReportWWW/
Section-A/A-recs-main.htm
Frame Walls
Best Practice: Best practice for frame wall construction involves advanced
framing techniques. However, these techniques are not required to achieve
30% space conditioning energy savings in the mixed-humid climate. If you
want to gain greater efficiency, more information on advanced framing can be
found in the guidance provided in this document for code officials, in the EEBA
Builders Guides, in DOE’s Fact Sheet on Wall Insulation, and on the Web at
www.buildingscience.com/housesthatwork/advancedframing/default.htm. If advanced
framing is to be used, a detailed plan should be developed showing framing placement.
ADVANCED FRAMING
Consider advanced framing
techniques when contructing walls.
Building America sponsored work by the Building Science Consortium and the U.S.
Army Construction Engineering Research Laboratory to develop an inset shear panel
for advanced framing in seismic regions. Information on the inset shear panel is
available at www.buildingscience.com/resources/walls/default.htm.
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Designers
External walls with 2x4 framing are adequate to reach the energy-efficiency targets of
this handbook in the mixed-humid climate. These walls should include the following
features:
• Exterior sheathing, preferrably insulating sheathing with joints taped to provide
a water and air barrier. Use insulating sheathing that does not have a film facing.
• Insulation may be R-19 friction-fit, kraft-faced fiberglass
insulation or blown-in cellulose insulation.
• Frame walls between the garage and the conditioned space, including bonus
rooms, should have unfaced or kraft-faced insulation.
• Rim joists: kraft-faced R-19 friction-fit batt insulation cut to fit.
• Penetrations: Foam seal or caulk all top-plate penetrations and exterior
wall penetrations.
• In addition to sealing all penetrations, air leakage through the walls should be
controlled by sealing the gypsum board. Pay particular attention to air-sealing
penetrations to garages and porches.
Masonry Walls
Masonry walls may be finished with stucco, wood, or other claddings. Best practices to
improve thermal efficiency include the following:
• Semi-vapor permeable rigid insulation should be installed on the interior of
wall assemblies and should be unfaced. Foil facing and polypropylene skins
should be avoided. Exterior insulation may also be installed.
• Wood furring should be installed over rigid insulation. The rigid insulation
should be continuous over the surface of the wall, except for a 2x4 furring at
the intersection with the ceiling. This blocking attaches directly to the masonry
block and serves as draft and fire stop. The rigid insulation abuts the blocking
but does not cover it or extend behind it.
FIGURE 11: Masonry Walls
with Interior Rigid Insulation
• Foam seal or caulk all top plate penetrations and exterior wall penetrations.
• Electrical boxes can be surface mounted to the masonry, avoiding chipping or
chiseling. The rigid insulation, furring, and gypsum board will build up around
the box for a flush finish.
• Use pressure treated lumber to frame out sub-jambs and spacers within window
and door rough openings.
• As with other walls, penetrations to the exterior or through top and bottom
plates should be foam sealed or caulked.
• In addition to sealing all penetrations, air leakage through the walls should be
controlled by sealing the gypsum board. Pay particular attention to air sealing
penetrations to garages and porches.
• When pouring the slab take care to create a seat in the concrete to accept the
block and seats in the concrete to act as drain pans where exterior doors and
sliding doors will be located.
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Designers
More information on masonry construction can be found in the Builders Guides
(Lstiburek 2002) and on the Web at the Building America Houses that Work section of
the Building Science Corporation Web site www.buildingscience.com/
housesthatwork/hothumid/orlando.htm. Look for the Orlando Profile. Window
flashing details can be found in the ASTM standard entitled Standard Practice for
Installation of Exterior Windows, Doors, and Skylights (ASTM 2002) and the EEBA
Water Management Guide. The Water Management Guide also contains information on
other approaches to draining masonry assemblies. The Trades
chapter contains a
building tips sheet for masonry walls.
Concrete Walls
Some builders are beginning to use poured concrete walls for residential construction.
For more information on this approach see Builder System Performance Package Targeting
30%-40% Savings in Space Conditioning Energy Use prepared by CARB (CARB 2004).
Windows
Best Practice: Specify efficient windows to control solar energy gains and to help reduce
heating and cooling loads. Some Building America experts recommend that, nationwide,
windows be used with a U-factor of 0.35 or lower and a SHGC of 0.35 or less. The
tradeoff in using a smaller SHGC is that the sun is blocked in both winter, when the sun
helps to heat the house, and summer, when the sun works against air conditioning. In
the mixed-humid climate the air conditioning season is longer than the heating season so
low SHGC windows are important. Note that ENERGY STAR qualification can be met
with windows at less stringent ratings.
Windows are a prominent feature of any wall. High-performance windows can be an
easy way to achieve ENERGY STAR qualification. Efficient windows will add expense
to your project, but will provide tremendous value in comfort, durability, and energy
savings. High-performance windows add so much to energy efficiency that smaller
cooling and heating equipment can often be specified, which may recapture much of
the cost. A voluntary rating system developed by the National Fenestration Rating
Council (NFRC) provides performance information for about half the windows
sold. The NFRC label contains ratings for the following features. You can find more
information about the NFRC on the Web at www.nfrc.org.
Les Bluestone, owner of Blue Sea
Development Company in New
York, said modeling of thermal
bridging performed by Building
America helped him cut heat loss
at a multifamily development in
New York that used precast con
crete panels for exterior walls and
wood framing for interior walls.
“The heat was being transferred
through the studs to the outside
walls, and that caused a consider
able amount of heat loss,” said
Bluestone. “So, before we did any
of the interior framing, we put up
a layer of rigid insulation (½-inch
expanded polystyrene board). We
wrapped the entire inside of the
building with this rigid insulation,
creating a real thermal break for
minimal transference. This made
a big, big difference.”
WINDOWS
Specify efficient windows to control
solar energy gains and to help
reduce heating and cooling loads.
FIGURE 12: NFRC Window Label
• U-factors take into account the entire window assembly and rate how well
the window prevents heat from passing through the window. The lower the
U-factor the better the window performs at stopping heat flow. U-factors are
the inverse of R-values used to measure the effectiveness of insulation. U-factor
values for windows generally fall between 0.20 and 1.2.
• SHGC is the solar heat gain coefficient, which measures how well the window
blocks heat caused by sunlight. The lower the SHGC rating the less solar heat
the window transmits. This rating is expressed as a fraction between 0 and 1.
• Visible transmittance (VT) measures how much light comes through a
window. VT is expressed as a number between 0 and 1. The bigger the
number the more clear the glass.
• Air leakage through a window assembly is included on most manufacturers’
labels, but is not required. The AL rating is expressed as the equivalent cubic
feet of air passing through a square foot of window area (cfm/sq.ft.) The lower
the AL, the less the window leaks. A typical rating is 0.2.
Building America Best Practices Series: Volume 4 – Builders and Buyers Handbook for
Improving New Home Efficiency, Comfort, and Durability in the Mixed-Humid Climate
Energy efficient windows are
comfortable to sit near and
provide protection for furniture
and window treatments.
Version 1, 9/2005 • DES-23
Designers
• Another optional rating is Condensation Resistance (CR), which measures
the ability of a product to resist the formation of condensation on the interior
surface of that product. The higher the CR rating, the better that product
is at resisting condensation formation. While this rating cannot predict
condensation, it can provide a credible method of comparing the potential
of various products for condensation formation. CR is expressed as a number
between 1 and 100, with a higher value representing more resistance to the
formation of condensation.
The Efficient Windows Collaborative operates a Web site that can help designers and
consumers choose windows. The Web site includes a tool that allows users to analyze
energy costs and savings for windows with different ratings. Visit the Web site at
www.efficientwindows.org/index.cfm.
The Web site also has fact sheets with comparisons for each state. These fact sheets
could make effective marketing tools. Also described on the Web site is a book entitled
Residential Windows: A Guide to New Technologies and Energy Performance (Carmody
et al. 2000), which offers homeowners, architects, designers, and builders a fascinating
look at the state of the art in window technology. Emphasizing energy performance,
the book covers every aspect of window design and technology: the basic mechanisms
of heat transfer; new products and rating systems; the effects of window frame material
and installation; and how to make the best decisions when purchasing windows.
OVERHANGS
Design roofs with overhangs
to shade and protect windows
and doors.
FIGURE 13: Overhangs
Overhangs
Best Practice: Design roofs with overhangs to shade and protect windows and doors.
Overhangs may take the form of eaves, porches, or other design features such as
awnings, pergolas, or trellises.
Single glazing is not recommended, but when a house has clear single glazing, lightcolored interior shades, overhangs, and combinations of shading devices significantly
reduce energy costs.
Reliance on any form of shading is not nearly as important when windows with a low
solar-heat-gain coefficient are used. Using a low-solar-gain low-E coating results in
great energy cost reductions for all conditions even with no shading. This is because
the glazing itself provides the necessary control of solar radiation, so shading measures
become less important in terms of energy use. For a description of the interactions
between window performance and shading, see the Efficient Windows Collaborative
Web site at www.efficientwindows.org.
Overhangs should be sized to account for differences in the angles of the sun during
winter and summer. Precise overhang dimensions should be calculated for each
latitude. Free and low-cost computer programs and tools are available to help. For
example a free program telling you the angle of the sun for any point in the country is
available at www.susdesign.com/sunangle/. Latitude, longitude, and elevation data can
be obtained at www.wunderground.com. Overhang dimensions can be calculated at
www.susdesign.com/overhang/index.html. For a listing of free and available-for
purchase energy models, including solar design tools, see DOE’s Building Technology
Program Web site at www.eere.energy.gov/buildng/index.cfm?flash=yes. Click on
Building America Best Practices Series: Volume 4 – Builders and Buyers Handbook for
Improving New Home Efficiency, Comfort, and Durability in the Mixed-Humid Climate
Winter
Sun
28o
Summer
Sun
75o
4 ft.
Sun angles for Louisville,
Kentucky. A four foot window
would need an overhang extending
22 inches with 12 inches of wall
above the window.
Version 1, 9/2005 • DES-24
Designers
Software Tools on the lower right side. A low-cost sun angle calculator is available from
the Society of Building Science Educators at www.sbse.org/resources/sac/index.htm.
Overhangs also provide protection from rain, hail, and the effects of overheating and
ultraviolet radiation on siding and windows.
Ceilings and Roofs
As indicated earlier, ceilings, roofs, and attics represent complex building assemblies. In
addition to the sealing and insulation approaches shown in the Air Sealing section, here
are additional insulation guidelines. These guidelines apply to traditionally ventilated
attics. Unvented attics must be tightly sealed and are not described in detail in this guide.
Carefully installed ceiling insulation helps to prevent ice dams.
• If attic access is provided, it must be insulated and weather-stripped.
• Use baffles to allow ventilation air to freely flow past insulation.
• Install an “energy” truss for more headroom at the eave to avoid compressing
insulation and allow for complete attic insulation coverage.
• Use dams to hold insulation away from openings and storage areas. Thick batt
insulation makes an excellent dam. Waxed cardboard, foam sheathing, and
other sheet goods can also be used as dams.
• Only recessed lights rated for “insulated ceiling and air tight” (ICAT) should
be installed in ceilings. See the section on electrical for more information.
Heating, Ventilating and Air Conditioning (HVAC)
Best Practice: For the best results in comfort, efficiency, and durability, HVAC system
design for both equipment and ducts must be integrated in the overall architectural
design. Work closely with your HVAC engineer, HVAC contractor or HERS rater to
properly design, size, and select your HVAC equipment. If done properly, you will save
money and go a long way with this single step toward improved energy efficiency and
comfort and substantial cost savings.
A well-designed house should have an HVAC system properly sized to its demands.
Proper equipment sizing ensures a comfortable environment and provides opportunities
to recapture some of the expense of an efficient building envelope. Rules of thumb for
equipment sizing do not work in modern homes and should not be used.
Unfortunately, rules of thumb are still prevalent. A Florida survey points out some of
the practices of HVAC contractors (Viera, Parker, Klonbergo, Sonn, and Cummings
1996). Although only a small percentage of Florida’s HVAC contractors responded,
the survey found that about one-third of respondents size air conditioning and
duct capacities based on square footage or other rules of thumb. Compounding the
problem, the rules were not consistently applied. Some respondents provided twice
as much capacity as others for a given square footage of floor area. Over one-third of
respondents indicated intentional oversizing of HVAC equipment on some jobs, in
order to avoid complaints, accommodate future expansions, enable quicker cooling
down of homes, and to allow for lower cooling set points by homeowners.
Building America Best Practices Series: Volume 4 – Builders and Buyers Handbook for
Improving New Home Efficiency, Comfort, and Durability in the Mixed-Humid Climate
HVAC
Integrate HVAC system design in
the overall architectural design.
“‘The recommended changes in
our practices meant we were able
to downsize our equipment by a
half-ton,’ explains Andrew Nevitt,
Medallion’s head architect. ‘Our
contractors were concerned that
they’d experience increased callbacks
because of comfort issues.’ That
hasn’t been the case. Medallion
is building all its homes to reach
ENERGY STAR performance
levels and is working with Building
America to learn practices that will
push the performance of its homes
even further.”
As reported in Professional Builder
3/1/03.
Version 1, 9/2005 • DES-25
Designers
Sizing Furnaces and Air Conditioners
RIGHT-SIZING
Best Practice: Right-size air conditioners and other HVAC equipment.
Right size air conditioners and other
HVAC equipment.
One estimate states that a Manual J calculation takes about 30 to 60 minutes for
an average home, using the measurements from construction drawings. Manual S
calculations require an additional 15 to 30 minutes (SBIC 2003). A single calculation
can work for multiple use of the same plans.
FIGURE14: ACCA Manuals
Four Sources for HVAC Design
The Air Conditioning Contractors of America (ACCA) has published simple but
effective methods for determining loads and sizing ductwork and heating and
cooling equipment.
• Manual J tells you how to calculate loads.
• Manual D tells you how to size ducts.
• Manual S guides you through the selection of appropriate heating and
cooling equipment to meet identified loads.
• Manual T gives you the basics for small buildings.
For more information or to purchase these documents on the Web, go to www.acca.org.
Photos by ACCA
Air Conditioner and Heat Pump Ratings
Best Practice: Central air conditioners should be rated at a minimum of 13 Seasonal
Energy Efficiency Ratio (SEER) for air cooling and heat pumps should be rated at a
minimum of 7.7 Heating Season Performance Factor (HSPF) for heating.
In September 2006 DOE will begin enforcing a 13 SEER standard for all
residential central air conditioners. For more information on this standard, visit
www.eere.energy.gov/buildings/appliance_standards.
RATINGS
Central air conditioners should be
rated at a minimum of 13 SEER and
heat pumps should be rated at
a minimum of 7.7 HSPF.
Consider using SEER-14 air conditioning equipment to achieve performance levels greater
than 30% savings. Equipment with SEER ratings up to 20 are now available. Currently,
ENERGY STAR-labeled central air conditioners have a minimum rating of SEER 12.
Heat Pumps
Heat pumps are preferable to electric resistance heating in mixed-humid climate. A unit
with a HSPF of 7.7 or more will reduce the electric consumption during heating by more
than 50% relative to electric resistance heating. The new standard will require that central
heat pumps have a minimum rating of 7.7 HSPF. Lists of all ENERGY STAR-rated
appliances can be found at www.energystar.gov/index.cfm?c=appliances.pr_appliances.
In colder areas where temperatures often fall below 30 degrees Fahrenheit (°F), typical air
source heat pumps require an electric resistance system to properly heat a home. This can
be an extremely costly method of supplemental heating; a backup gas or propane furnace
may be a cost-effective alternative. A newly-designed cold climate heat pump is under
development but not readily available.
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Designers
Central Gas-Fired Furnace
Best Practice: Sealed combustion gas furnaces should be specified for central gas-fired
heating systems. ENERGY STAR-labeled furnaces meet a minimum Annual Fuel
Utilization Efficiency (AFUE) of 90.
Sealed Combustion
Sealed combustion means than an appliance acquires all air for combustion through
a dedicated sealed passage from the outside, to a sealed combustion chamber, and all
combustion products are vented to the outside through a separate, dedicated sealed vent.
Mechanical Ventilation
Best Practice: Building America recommends that whole-house mechanical ventilation
be provided as specified in ASHRAE Standard 62.2. Recommended ventilation
systems for indoor air quality include mechanical exhaust, systems that supply air, or a
combination of the two.
A New Standard in Residential Ventilation
In Autumn 2003, the American Society of Heating, Refrigerating And Air-Conditioning
Engineers (ASHRAE) established a new standard for indoor ventilation in residences. The
standard is ASHRAE 62.2, Ventilation and Acceptable Indoor Air Quality in Low-Rise Residential
Buildings (ASHRAE 2003). The following information is adapted from the forward that is
published with the standard:
The standard contains three main sets of requirements and a host of secondary
ones. The three primary sets involve whole-house ventilation, local exhaust, and
source control. Whole house ventilation is intended to dilute the unavoidable
contaminant emissions from people, materials, and background processes. Local
exhaust is intended to remove contaminants from specific rooms, such as kitchens
and bathrooms, where pollutant sources are produced. And source control measures
are included to deal with other anticipated sources. The standard’s secondary
requirements focus on properties of specific items, such as sound and flow ratings
for fans and labeling requirements.
The standard is principally about mechanical ventilation, but its purpose is to
provide acceptable indoor air quality. The most effective way for keeping exposure
to pollutants low is to keep them from being released to the general indoor
environment in the first place.
ASHRAE is planning to publish guidance documents on meeting this standard.
GAS FURNACES
Specify sealed combustion gas
furnaces for central gas-fired systems.
Efficiency Measures for Air
Conditioners, Heat Pumps,
and Furnaces
The Annual Fuel Utilization
Efficiency (AFUE) measures the
amount of fuel converted to heat
at the furnace outlet in proportion
to the amount of fuel entering
the furnace. This is commonly
expressed as a percentage. A
furnace with an AFUE of 90 could
be said to be 90% efficient.
The Seasonal Energy Efficiency
Ratio (SEER) is a measure of
equipment energy efficiency over
the cooling season. It represents
the total cooling of a central
air-conditioner or heat pump (in
Btu) during the normal cooling
season as compared to the total
electric energy input (in watt-hours)
consumed during the same period.
The Heating Season Performance
Factor (HSPF) is a measure of a heat
pump’s energy efficiency over one
heating season. It represents the
total heating output of a heat pump
(including supplementary electric
heat) during the normal heating
season (in Btu) as compared to the
total electricity consumed (in Watthours) during the same period.
VENTILATION
Whole-house mechanical
ventilation should be provided as
specified in ASHRAE Standard 62.2.
Recommended ventilation systems
for indoor air quality include
continuous low-speed exhaust
fans or balanced ventilation
• Base Rate Ventilation: controlled mechanical ventilation at a minimum base
rate of 15 CFM for the master bedroom, plus 0.01 CFM for each square foot
of conditioned area, and 7.5 CFM for each additional bedroom, should be
provided, as listed in ASHRAE 62.2.
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Designers
FIGURE 15: Outside Vents
“Everyone in Oklahoma has
allergies and asthma. I love to see
comments on our surveys like ‘we
really believe we have less allergies
and asthma in this house.’”
Vernon McKown, the co-owner
of Ideal Homes in Oklahoma, who
adds that he believes the fresh air
ventilation system with the fan
recycler is the product his
customers appreciate the most.
Source: Building Science Consortium
• Spot Ventilation: intermittent spot ventilation of 100 CFM should be
provided for the kitchen; all kitchen range hoods must be vented to the
outside (no recirculating hoods). Intermittent spot ventilation of 50 CFM or
continuous ventilation of 20 CFM, should be provided for each washroom/
bathroom. Fans should be quiet, with a sound rating of less than 1.5 sonnes.
Central fan-integrated supply ventilation can be an easy and inexpensive way to
provide outside air to the HVAC system. This system provides fresh, filtered,
outside air in a controlled amount using the existing HVAC delivery system for even
distribution and mixing.
Most of the Building America teams have designed and field-tested these ventilation
systems. The systems involve exterior air intakes, ductwork running to the return air
side of the HVAC system, dampers to allow control of the air intake, and electronic
controls to ensure that the HVAC fans operate frequently enough to draw in adequate
fresh air. For an example of these systems, see www.buildingscience.com/resources/
mechanical/air_distribution.pdf for more detailed information.
DUHUMIDIFICATION
Equip your home with a
dehumidification system if needed.
Supplemental Dehumidification
Best Practice: Some Building America teams recommend that houses be equipped
with a dehumidification system in the mixed-humid climate or designed so that a
dehumidifier can be easily added if needed.
In mixed humid climates, high exterior humidity may occasionally require
dehumidification to maintain reasonable interior moisture levels. Moisture may also
be controlled with exhaust ventilation in bathrooms and kitchens. Some Building
America teams recommend that a dehumidification system serve the insulated
basement area (Broniek 2003).
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Designers
Compact Air Distribution System
FIGURE 16: Duct Run Configurations
Best Practice: Make duct runs as short as
possible.Duct may also be run through
a conditioned crawlspace, conditioned
basement, or conditioned attic.
An efficient building envelope and
efficient HVAC equipment allow for
a compact air distribution system.
Conditioned air may be discharged
from walls (see the discussion in
the next section on chase design) or
from ceiling diffusers up to 12 feet
from the window wall in most cases
without compromising comfort. Such
“inside throw” layouts cut ductwork
runs, saving money and reducing the
amount of ductwork that may run in
unconditioned space.
DUCT RUNS
Make duct runs as short
as possible. Duct may also be run
through a conditioned crawlspace,
conditioned basement, or
conditioned attic.
DUCT SEALING
Seal all ductwork and air handlers
with mastic and seal duct boots to
sheetrock connections.
FIGURE 17: Mastic
Seal All Ducts and Air Handlers
Best Practice: Seal all ductwork seams
and connections to air handlers with
UL181-approved water-based mastic
and seal drywall connections with caulk
or foam sealant.
Sealing ductwork is very important.
Leaky ductwork in an unconditioned
attic or crawlspace can draw unhealthy
air into the air distribution system.
Sealing ducts with mastic is desirable
even for ducts located in conditioned
spaces. Properly sealed ducts make sure
air gets to the spaces intended, rather
Source: Building Science Consortium
than leaking into a plenum space. It also
minimizes the chances of creating pressure differentials from space to space that would
induce airflow through the envelope. The process of sealing each joint reduces the
chances of unconnected ductwork, a surprisingly common mistake.
Mastic provides the most reliable duct sealing method for new construction. All
ductwork, including the air handler compartment (which typically has many leaky
joints), should be mastic sealed.
DOE research has found that some tapes perform adequately for sealing ducts,
particularly fiberglass duct board. However, good performing tapes may be difficult to
identify and traditional duct tape (cloth-backed rubber adhesive tapes) should never be
used to seal ducts, even if it meets UL ratings. Do not use sealing tapes for structural
purposes. Tapes have low tensile strength and should not be used to mechanically
support ducts. A technical report (Walker, Sherman, Modera, and Siegel 1998) on duct
Building America Best Practices Series: Volume 4 – Builders and Buyers Handbook for
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Mastic provides the most reliable duct
sealing method for new construction.
“Sealing the ducts with mastic
is I think the single most
important thing that anyone
should do. Sealing gets leakage
rates down to about 2%.
Not doing duct sealing on
new construction is extremely
short sighted. Mastic will last
the life of the system, while
conventional duct tape can fail
within a year.”
Lucian Kragiel, Co-owner of
Atlantic Design and Construction
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Designers
sealants can be found on the Web at http://ducts.lbl.gov/Publications/lbl-41118.pdf
and a less technical article (Sherman and Walker 1998) on similar research can be
found at www.homeenergy.org/archive/hem.dis.anl.gov/eehem/98/9807.html.
California Title 24 residential building standards requires that duct sealants meet UL 181,
UL 181A, UL 181B, or UL 723 (for aerosol sealants). The California Energy Commission
has approved a cloth-backed duct tape with a special butyl adhesive (CEC 2005).
Standards for Duct Sealants
Underwriters Laboratories, Inc. (UL) publishes several standards that relate to duct
sealants, the most important of which is UL 181. It deals with ducts in general, with UL
181A covering field-assembled duct-board, and UL 181B covering flex duct systems.
Each standard includes test procedures for sealants. Duct tapes and packing tapes that
pass UL 181B are labeled “UL 181B-FX.” Mastics can pass 181A or B and
are labeled “UL 181A-M” or “UL 181B-M.” Foil tapes are designated with a P.
Most tapes that are labeled 181B-FX are duct tapes. UL 181A and 181B appear to do a
good job of testing for safety, tensile strength, and initial adhesion. However, they may
not do a good job of rating how well sealants seal typical duct leaks or how well they stay
sealed under normal conditions.
The California Energy Commission has approved a cloth-backed duct tape with a special
butyl adhesive (CEC 2005).
Adapted from Sherman and Walker 1998
Properly sized and sealed ducts, kept
inside conditioned space, improve
performance and reduce cost.
Source: IBACOS
Ducts and Air Handlers in Conditioned Space
Best Practice: Ducts and air handlers should be placed in conditioned spaces to the extent
possible. Extreme temperatures and humidity levels can be found in unconditioned spaces
and create an unfavorable environment for ducts and air handlers.
DUCT RUNS
Ducts and air handlers should be
placed in conditioned spaces to the
extent possible.
Ducts and air handlers perform best when placed within conditioned space. Do not
install ductwork in exterior walls. Keeping ducts inside conditioned space may require
one of several strategies, such as:
1) Placing ducts in a chase designed to run through a central corridor below
the attic or on top of the ceiling through the attic. If the chase runs
through the attic, it must fit within the roof truss design and will be
covered with insulation. For more information on designing and building
an interior chase see the report, Design and Construction of Interior Duct
Systems (McIlvaine, Beal, and Fairey 2001), available on the Web at
www.fsec.ucf.edu/bldg/baihp//pubs/interior_ducts.pdf.
2) Insulating and sealing the underside of the roof sheathing to create a
conditioned attic. This strategy requires tightly sealing the roof structure,
especially where it connects with the walls, to avoid the entry of outside air.
This technique essentially requires building a non-vented roof assembly. For
more information on this technique see www.buildingscience.com/resources/
roofs/unvented_roof_summary_article.pdf. This approach may require a
variance from local code officials.
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Designers
3) In houses with a crawlspace, insulating and sealing the exterior walls of the
crawlspace so that it becomes a conditioned space, such as a mini basement.
This strategy requires treating the crawlspace much like a living space with
conditioned air supply, moisture control, and air returns to the HVAC
system. More information on this approach can be found in the section on
Foundation Systems.
Air handlers/furnaces should be placed inside conditioned space.
Duct Insulation
Best Practice: Ducts in unconditioned spaces must be insulated.
To the extent possible, ducts should be placed inside conditioned space. In conditioned
spaces, they require minimal insulation. If the ducts are placed in unconditioned spaces,
due to the extreme summer temperatures in these spaces, 10% to 30% of the energy
used to cool the air can be lost to conduction through the duct surfaces. Therefore,
they must be insulated. ENERGY STAR recommends R-8 insulation levels for supply
ducts in unconditioned attics and R-4 in crawlspaces (EPA 2000, available on the Web
at www.energystar.gov/ia/new_homes/features/DuctInsulation1-17-01.pdf) (based on
Treidler et al. 1996).
INSULATING DUCTS
Ducts in unconditioned spaces
must be insulated.
FIGURE 18: Jump Ducts
FIGURE 19: Jump Ducts
Source: IBACOS
Source: Building Science Corporation
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Designers
Transfer Grilles and Jump Ducts
Best Practice: Use jump ducts and transfer grilles and other return pathways to
maintain balanced pressure in rooms that are often isolated from the rest of the house
by a closed door, such as a bedroom.
To maintain balanced pressure, air must be returned from each room to the central
HVAC equipment. One way to do this would be to add a ducted return from each
room. However, this would be expensive and consume a lot of space. A cost-effective
approach is to provide a central return and make sure that there are transfer grilles or
transfer ducts, of adequate size, that allow air to pass from individual rooms to the
central return even when doors are closed. Figure 18 illustrates different approaches
to creating paths to equalize air pressure and allow air to return to HVAC equipment.
When designing registers and transfer grilles, place them high on the wall in areas
where furniture may block air movement.
BALANCED PRESSURE
Use jump ducts and transfer
grilles and other return pathways
to maintain balanced pressure in
bedrooms and other isolated rooms.
Draw Duct Layouts on Plans
Best Practice: Clearly identify on plans and drawings the locations, sizes, and types for
all duct work and registers, including the heating and cooling supply ducts, passive
return air ducts or transfers, the locations for the mechanical ventilation air inlet (at
least 8 feet away from any exhausts or condensers), and all exhaust outlets. If chases or
other spaces are to be dedicated to duct runs, indicate this on the plans.
DUCT WORK LOCATION
Clearly identify on plans and
drawings the locations, sizes, and
types for all duct work and registers.
This level of detail can be referenced in contract documents so you know exactly what you
will be getting. These documents can provide guidance in the field for proper installation.
Energy Performance and Commissioning
Best Practice: Air conditioners and heat pumps should be evaluated after installation
with a duct pressure test and, if needed, a smoke test to identify the location of leaks.
Procedures are discussed in the Site Supervisors
chapter.
EVALUATION
Evaluate air conditioners and heat
pumps after installation.
Building Science Corporation has identified performance testing as a key reason for
substantial reductions in callbacks (BSC 2003).
Occupant Health and Safety
The following best practices should be included in the house design:
• All combustion appliances in the conditioned space must be sealed combustion
or power-vented. Specifically, any furnace inside conditioned space shall be
a sealed-combustion 90%+ (AFUE of 90 or greater) unit. Any water heater
inside conditioned space shall be power vented or power-direct vented.
Designs that incorporate passive combustion air supply openings or outdoor
supply air ducts not directly connected to the appliance should be avoided.
Gas cooking ranges shall follow the practices described in the second bullet.
• Use sealed-combustion gas fireplaces to eliminate the threat of harmful combustion
gases from entering the house. All fuel-burning fireplaces should have sealed
combustion and be properly vented to the outside. If not properly vented and
sealed, the fireplace can produce harmful combustion pollutants that may be emitted
into the home, such as carbon monoxide, nitrogen dioxide, and sulfur dioxide.
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• Provide filtration systems for forced air systems that provide a minimum
atmospheric dust spot efficiency of 30% or MERV of 6 or higher. MERV
(Minimum Efficiency Reporting Value) is a measure of an air filter’s efficiency
at removing particles. A fiberglass panel filter may have a MERV of 4 or 5.
Critical areas in hospitals may use a MERV 14 filter. Electronic air cleaners
should be used with caution because the ozone they produce may affect
sensitive individuals.
• Indoor humidity should be maintained in the range of 25% to 60% by
controlled mechanical ventilation, mechanical cooling, or dehumidification.
See www.buildingscience.com/resources/moisture/relative_humidity_0402.pdf.
• Carbon monoxide detectors (hard-wired units) shall be installed (at one per
every approximate 1,000 square feet) in any house containing combustion
appliances and/or an attached garage.
• Maximize hard surface areas (tile, vinyl, hardwood) to better manage dust for
health purposes. For slab-on-grade houses, it also reduces the cooling loads.
• Information relating to the safe, healthy, comfortable operation and
maintenance of the building and systems that provide control over space
conditioning, hot water, or lighting energy use shall be provided to occupants.
Mechanicals Management and Appliances
FIGURE 20: Additional Plumbing Air
Sealing Building Tips can be found
in the Trades Chapter.
Plumbing
Water heater efficiency is described by the
energy factor rating. The Consumers’ Directory
of Certified Efficiency Ratings, Gas Appliance
Manufacturers Association (GAMA) provides a
concise listing of energy factors for water heaters
of all fuel types at www.gamanet.org.
Best Practice: Do not install plumbing
PLUMBING SEALING
in exterior walls. Seal around plumbing
penetrations in all exterior surfaces, surfaces that
border on unconditioned spaces, and between
floors. Use fire-resistant sealant in plates
between floors.
Seal plumbing penetrations in
exterior surfaces and keep plumbing
out of exterior walls.
Best Practice: Water heaters can be located
WATER HEATERS
in the basement or a conditioned crawlspace
(space permitting) or enclosed within a closet.
If enclosed, ventilation grilles may be needed to
provide combustion air. Water heaters located
in conditioned spaces should be power vented
or power-direct vented
Water heaters located in a
conditioned spacemust be powervented or power-direct vented.
Air admittance vents may be accepted in some jurisdictions and can help reduce the
quantity of needed vent pipes. More information can be found at www.toolbase.org.
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Water Heaters
Water heaters come in many shapes, sizes, and efficiencies. The Oregon Department of
Energy maintains a list of high-efficiency water heaters that qualify for state tax credits.
The list contains high-efficiency gas combustion water heaters, instantaneous (tankless)
water heaters, and water heating heat pumps. You may consider these products for your
projects. The tax credits only apply to Oregon installations by Oregon taxpayers. See the
list at: www.energy.state.or.us/res/tax/appheat.htm.
Best Practice: Be sure to specify insulation requirements for pipes, especially pipes that
will be covered by the slab, or will otherwise be inaccessible.
SPECIFY INSULATION
REQUIREMENTS
Be sure to specify insulation
requirements for pipes, especially
pipes that will be inaccessible.
Electrical
Best Practice: Seal around wires penetrating
all exterior surfaces, surfaces that border on
unconditioned spaces, and between floors.
Use fire-resistant sealants between floors.
If recessed downlights are to be used they
should be rated for insulated ceilings and
airtight (ICAT).
FIGURE 21: Additional Electrical Air
Sealing Building Tips are available in
the Trades chapter.
ICAT is a combination of two standards.
The first is ASTM E283, the standard for
testing restricted air movement (ASTM
2004) and the second is Underwriters
Laboratory standard for direct burial in
insulation contained in the Luminaires
standard (UL 1598). The ICAT standard
originated in the State of Washington
building code and now, as part of the
International Energy Efficiency code,
covers almost 75% of the country’s
population. See the Trades
chapter
for Building Tips for electricians for
more information.
ELECTRICAL SEALING
Seal all wire penetrations.
Eastern Dakota Housing Alliance
found that extra features like
on-demand water heaters, extra
polystyrene insulation, and
fluorescent lighting can all add
to a homes’ energy efficiency.
“The water heater made a very
big difference,” said Lisa Rotvold,
EDHA’s director. “It was a costly
item but it has a good payback
for us.”
Consider the use of recessed downlights and other fixtures that qualify for ENERGY
STAR labels. Highly energy-efficient recessed downlight fixtures that have undergone
stringent testing are available for purchase at the following DOE sponsored Web site:
www.pnl.gov/cfldownlights/. The lights featured are ICAT rated and hard-wired for
compact fluorescent bulbs. Fixed prices have been negotiated for the featured fixtures.
Using compact fluorescent lamps in lighting fixtures will reduce energy usage and lower
the cooling load.
Appliances
Major appliances meet high-energy efficiency standards using current appliance ratings.
Only those appliances in the top one-third of the DOE Energy Guide rating scale
should be selected (see list at: www.eere.energy.gov/consumerinfo/energy_savers/
appliances.html). One approach is to use appliances with the ENERGY STAR label.
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Sources & Additional Information
• Air Conditioning Contractors of America. Manual D: Residential Duct Systems. ACCA, Arlington, VA. www.acca.org.
• Air Conditioning Contractors of America. Manual J: Residential Load Calculation, Eighth Edition. ACCA,
Arlington, VA. www.acca.org.
• Air Conditioning Contractors of America. Manual S: Residential Equipment Selection. ACCA, Arlington, VA.
www.acca.org.
• Air Conditioning Contractors of America. Manual T. Air Distribution Basics for Residential and Small
Commercial Buildings. ACCA, Arlington, VA. www.acca.org.
• The American Society of Civil Engineers standard (number 32-01). Design and Construction of Frost-Protected
Shallow Foundations.
• American Society of Heating, Refrigerating, and Air-Conditioning Engineers, INC (ASHRAE). 2003. ASHRAE
Standard: Ventilation and Acceptable Indoor Air Quality in Low-Rise Residential Buildings. ASHRAE, Atlanta, GA.
• ASTM 2002. Standard Practice for Installation of Exterior Windows, Doors, and Skylights. ASTM E2112-01.
• ASTM 2003. WK2469 New Standard (Formerly E1465-92) Guide for Radon Control Options for the Design and
Construction of New Low Rise Residential Buildings.
• ASTM 2004. Standard Test Method for Determining Rate of Air Leakage through Exterior Windows, Curtain Walls,
and Doors Under Specified Pressure Differences across the Specimen. ASTM E283-04.
• Broniek, John. 2003. Builder System Performance Packages Technical Report. Prepared by IBACOS for the Building
America Program. www.buildingamerica.gov
• Building Energy Codes Resource Center. Details for Mechanically Vented Crawlspaces - Code Notes.
www.energycodes.gov/support/code_notes.stm
• Building Science Corporation (BSC). 2002. 10. Case Study Material: Conditioning Air in the Humid South. National
Renewable Energy Laboratory, Golden, CO.
• Building Science Corporation (BSC). 2003. 9. BSC Final Report: Lessons Learned from Building America
Participation, February 1995-December 2002. National Renewable Energy Laboratory, Golden, CO.
• Building Science Corporation. 2003b. 1.C.2.1 Report Expert Meeting Summary. National Renewable Energy
Laboratory, Golden, CO.
• Building Science Corporation. 2004. Houses that Work. www.bsc.com
• California Energy Commission. 2005. 2005 Residential Compliance Manual. Sacramento, CA.
www.energy.ca.gov/2005publications/CEC-400-2005-005/CEC-400-2005-005-CMF.pdf.
• CARB (Consortium for Advanced Residential Buildings). 2004. Builder System Performance Package Targeting
30%-40% Savings in Space Conditioning Energy Use: NREL/SR-550-34560. National Renewable Energy
Laboratory, Golden, CO. Available at www.buildingamerica.gov.
• Carmody, John, Stephen Selkowitz, Dariush Arasteh and Lisa Heschong. 2000. Residential Windows:
A Guide to New Technologies and Energy Performance. W. W. Norton and Company, New York.
www.wwnorton.com/npb/welcome.htm.
• U.S. Department of Energy (DOE). 2000. Technology Fact Sheet on Weather Resistive Barriers. DOE/GO-102000
O769, Washington D.C. Available on the Web at www.eere.energy.gov/buildings/documents/pdfs/28600.pdf.
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• U.S. Department of Energy (DOE), Office of Building Technology. 2002. Technology Fact Sheet: Basement Insulation.
• U.S. Department of Energy (DOE). 2000. Energy Savers Fact Sheet on Vapor Diffusion Retarders and Air Barriers
www.eere.energy.gov/consumerinfo/factsheets/bd4.html
• Edminster, Ann, Betsy Pettit, Kohta Ueno, Stephanie Menegus, and Steven Baczek. 2000. “Case Studies
in Resource-Efficient Residential Building: The Building America Program.” 2000 ACEEE Summer Study
Proceedings. ACEEE, Washington, D.C.
• Garrison, Tim. 2004. Nation’s Building News Online, 27 April 2004. www.nbnnews.com.
• IBACOS. 2002. Best Practices: Consider the Crawlspace.
• IBACOS. 2002. Don’t Forget About the Basement. Prepared by IBACOS for the Building America Program.
www.buildingamerica.gov
• Institute for Business and Home Safety. The IBHS has building guidelines and public information. www.ibhs.org.
• Lstiburek, Joseph. 2001. EEBA Builders Guide: Mixed-Humid Climates. EEBA, Minneapolis, MN. www.eeba.org/bookstore.
• Lstiburek, Joseph. 2002. EEBA Builders Guide: Hot and Humid Climates. EEBA, Minneapolis, MN.
www.eeba.org/bookstore.
• Lstiburek, Joseph. 2003. EEBA Water Management Guide. EEBA, Minneapolis, MN. www.eeba.org/bookstore.
• Lstiburek, Joseph. 2004. Builders Guide to Cold Climates. www.eeba.org/bookstore
• McIlvaine, Janet; David Beal; and Philip Fairey, III. 2001. Design and Construction of Interior
Duct System. Report Number FSEC-PF-365-01, Florida Solar Energy Center, Cocoa, FL.
www.fsec.ucf.edu/bldg/baihp//pubs/interior_ducts.pdf.
• Parker, D.S.; J. R. Sherwin; and M. T. Anello, 2001. “FPC Residential Monitoring Project: New Technology
Development — Radiant Barrier Pilot Project,” Contract Report FSEC-CR-1231-01, Florida Solar Energy Center,
Cocoa, FL. www.fsec.ucf.edu/bldg/pubs/rbs/index.htm.
• Rudd, Armund. 2003. Refrigeration System Installation and Startup Procedures, and Air Conditioning System
Efficiency. Building Science Corporation, Westford, MA.
www.buildingscience.com/resources/mechanical/air_conditioning_equipment_efficiency.pdf.
• Sherman, Max and Iain Walker. 1998. “Can Duct Tape Take the Heat?” Home Energy, Berkeley, CA.
www.homeenergy.org/898ductape.title.html.
• Straube, John. 2001. Canadian Architect. “Wrapping it Up”. May, 2001. www.cdnarchitect.com.
• (SBIC) Sustainable Buildings Industry Council. 2003. Green Building Guidelines: Meeting the Demand for LowEnergy, Resource-Efficient Homes. U.S. DOE. Washington, D.C. document available at www.SBICouncil.org.
• Treidler, B.; M.P. Modera; R.G. Lucas; J.D. Miller. 1996. Impact of Residential Duct Insulation on HVAC Energy
Use and Life-Cycle costs to Consumers. ASHRAE Transactions: Symposia, AT-96-13-4. American Society of
Heating, Refrigerating, and Air Conditioning Engineers, Atlanta, GA.
• University of Minnesota, Building Foundations Research Program. Frost Protected Shallow Foundations Design
Specifications. www.buildingfoundation.umn.edu/MHFAfrostFoundation.htm
• University of Minnesota, Building Foundations Research Program. Minnesota Energy
Code Building Foundation Rule: Amendment Proposal Development Project Final Report.
www.buildingfoundation.umn.edu/FinalReportWWW/Section-A/A-recs-main.htm
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• U.S. Environmental Protection Agency. 1994. Model Standards and Techniques for Control of Radon in New
Residential Buildings.
• U.S. Environmental Protection Agency. 2000. Duct Insulation: Air Distribution System Improvements. EPA 430
97-028. Washington, D.C. www.energystar.gov/ia/new_homes/features/DuctInsulation1-17-01.pdf.
• U.S. Environmental Protection Agency. 2001. Building Radon Out: A Step by Step Guide on How to Build Radon
Resistant Homes. www.epa.gov/199/radon/images/buildradonout.pdf.
• Viera, Robin K.; Parker, Danny S.; Klongerbo, Jon F.; Sonne, Jeffrey K.; Cummings, Jo Ellen. 1996.
“How Contractors Really Size Air Conditioning Systems.” Florida Solar Energy Center, Cocoa, FL.
www.fsec.ucf.edu/bldg/pubs/ACsize/index.htm.
• Walker, I.; M. Sherman; M. Modera; and J. Siegel. 1998. Leakage Diagnostics, Sealant Longevity, sizing and
Technology Transfer in Residential Thermal Distribution Systems. Lawrence Berkeley National Laboratory, Berkeley,
CA. http://ducts.lbl.gov/Publications/lbl-41118.pdf.
• Yost, Nathan. May 2003. “The Case for Conditioned Unvented Crawlspaces.” Building Safety Journal.
www.buildingscience.com/resources/articles/24-27_Yost_for_author.pdf.
• Yost, Nathan, and Joseph Lstiburek. 2002. Basement Insulation Systems. Prepared by the Building Science
Consortia for the Building America Program. www.buildingamerica.gov
Web Sites Not Included with Published Documents Above
(See Appendix V for more information on Web sites.)
• www.blueprintforsafety.org
• www.buildingamerica.gov
• www.buildingscience.com/housesthatwork/airsealing.htm
• www.buildingscience.com/housesthatwork/buildingmaterials.htm
• www.buildingscience.com/housesthatwork/hothumid/montgomery.htm
• www.buildingscience.com/housesthatwork/hothumid/orlando.htm
• www.buildingscience.com/resources/mechanical/advanced_space_conditioning.pdf
• www.buildingscience.com/resources/moisture/relative_humidity_0402.pdf
• www.buildingscience.com/resources/roofs/unvented_roof_summary_article.pdf
• www.buildingscience.com/resources/walls/problems_with_housewraps.htm
• www.buildingscience.com/resources/walls/default.htm
• www.certainteed.com/pro/insulation
• www.crawlspaces.org
• www.eere.energy.gov/buildings
• www.eere.energy.gov/consumerinfo/energy_savers/appliances.html
• www.eere.energy.gov/consumerinfo/energy_savers/r-value_map.html
• www.eere.energy.gov/consumerinfo/factsheets/landscape.html
• www.eere.energy.gov/weatherization/hazard_workshop.html
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Designers
• www.efficientwindows.org/index.cfm
• www.energycodes.gov
• www.energy.state.or.us/res/tax/appheat.htm
• www.energystar.gov/index.cfm?c=bop.pt_bop_index
• www.epa.gov/iaq/whereyoulive.html
• www.epa.gov/radon/zonemap.html
• www.fema.gov
• www.fsec.ucf.edu/bldg/science/basics/index.htm
• www.fsec.ucf.edu/bldg/pubs/rbs/index.htm
• www.gamanet.org
• www.ibacos.com/bestprac.html
• www.ibacos.com/ghome/Aug03/Sug2003_bp_brick.html
• www.ibacos.com/ghome/Aug04/Aug2004_Water.html
• www.ibacos.com/ghome/Jan04/bestpractice.pdf
• www.ibacos.com/ghome/Jan04/Jan_BPWebBasements.html
• www.ibacos.com/ghome/June03/wtrhtr.html
• www.ibacos.com/ghome/March03/march03_bestpractices_roofflashing.html
• www.ibacos.com/ghome/March03/march03_cover.html
• www.ibacos.com/ghome/March04/Mar_BPRoofs.html
• www.ibacos.com/ghome/March04/Mar_Tech_VentedAttics.html
• www.ibacos.com/ghome/Oct03/duct.html
• www.ibacos.com/ghome/Winter05/winter05_bestpractices_drainage_plane.html
• www.ibacos.com/hpl.html
• www.ibacos.com/pubs/Newsletter-July02.pdf
• www.ibacos.com/pubs/Newsletter-July02.pdf#page=3
• www.nahbrc.org/docs/mainnav/moistureandleaks/792_moisture.pdf
• www.natresnet.org
• www.nfrc.org
• www.ornl.gov/sci/roofs+walls/insulation/ins_16.html
• www.ornl.gov/sci/roofs+walls/radiant/rb_01.html
• www.pnl.gov/cfldownlights/
• www.sbse.org/resources/sac/index.htm
• www.susdesign.com/sunangle
• www.toolbase.org
• www.uky.edu/Agriculture/Entomology/entfacts.htm
• www.wunderground.com
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Site Supervisors
Tools to help with project management
INTRODUCTION
In the chain of events that results in a finished home, the site supervisor (or project
manager) has the critical job of turning ideas into reality. The site supervisor’s job is
to make sure everything happens. Plans must be correct, permits must be in order,
contracts must be signed, subconractors must be scheduled, materials must be on site,
and it all must happen on schedule. Successful construction of an energy-efficient
home is essentially the same as other homes, although a few details are different and
can demand more careful scrutiny because of the interdependencies in a systemsdesigned house.
Site supervisors working to build energy-efficient homes can generally do their jobs
as they already know how, with a few simple but important changes. There are
three keys to constructing any quality home—managing expectations, managing
the schedule, and controlling quality and costs. This section will explain how to
incorporate those three keys into your construction process.
An energy-efficient home built using these Building America recommendations
looks a lot like any other home. It will maintain its visual appeal and style. The key
points at which it differs typically involve more efficient heating, ventilating, and air
conditioning (HVAC) equipment (including ducts), an engineered HVAC system
design, a supply of outside air for ventilation, humidity control, better windows,
better insulation, and better air sealing. The Designers
chapter contains best
practices recommendations on the features energy-efficient homes should include.
Many builders make the comment that it’s not the quantity of changes that make an
energy-efficient home, but the quality that is put into building the home.
Of course, it is not always easy for a
site supervisor to control all aspects of a
subcontractor’s work. It may be necessary,
especially while these best practices are new
ideas, to prioritize activities and “pick your
battles.” In the mixed-humid climate, the
top priorities are: 1) window selection and
installation, 2) HVAC sizing and installation.
“The things that we are doing are
not rocket science. It is attention
to detail and a systems approach.”
Lisa Rotvold, Director of the not-forprofit Eastern Dakota Housing Alliance
Managing Expectations
Taking action in
your community
HOMEOWNERS
Shopping for value,
comfort, and quality
MANAGERS
Putting building
science to work for
your bottom line
MARKETERS
Energy efficiency
delivers the value that
customers demand
SITE PLANNERS
& DEVELOPERS
Properly situated houses
pay big dividends
DESIGNERS
Well-crafted designs
capture benefits for builders,
buyers, and business
SITE SUPERVISORS
Tools to help with
project management
TRADES
Professional tips for fast
and easy installation
CASE STUDIES
Bringing it all together
A project manager who can foster a set of shared expectations among the important
players in his or her building team can successfully build efficient houses. Two goals
should influence the project manager’s actions at the start of the project:
• Make sure subcontractors and in-house workers understand what you want
• Eliminate the need for unknowledgeable (and often unskilled) laborers to
make design decisions.
The following best practices will help meet these goals.
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Develop a Work Plan
Decide who is going to do what. Will the plumber install insulation behind the tub
or will the framer, or some other trades person? Develop a schedule for the order that
activities should occur to be sure that actions are done in a reasonable order and that
no actions will be forgotten. Be sure that all needed materials are on the site when the
activity is scheduled to take place. More information on scheduling is included in the
Managing Execution section.
Plans – Get Them Right
“It is just as easy to do things
right as it is to do things
wrong. Once the contractors
and subcontractors understand
what our definition of right
is, then it is not a problem
[building to Building America
standards].”
Les Bluestone, owner of Blue Sea
Development Company in New York
Best Practice: Before starting a project ensure that plans are correct and that you have
everything you need to go forward. Once you have the plans you need, follow them.
Existing stock plans will likely need to be modified to both include necessary changes
and to add details not commonly included in residential prints. See the Designers
chapter for a description of design best practices.
PLANS
Make sure they are correct
and follow them closely.
A well-designed home should have well-designed plans that include everything necessary
to explain expectations to the subcontractors. Some points that should be included are
• HVAC design details and duct layout. The duct layout must be included on
a floor plan. The duct and diffuser sizes, quantities, and locations must be
installed as specified. Subcontractors should be contractually obligated to these
specifications. Performance requirements, such as seasonal energy efficiency
ratio (SEER) and annual fuel utilization efficiency (AFUE), for system
components should be specified on the plans.
• Framing plan. If advanced framing is to be included in the design, a detailed
plan is needed showing how advanced framing techniques will be applied.
These should detail the placement of studs to ensure proper “stacking” in twostory homes and should show details of window and door framing. Advanced
framing is not required to achieve 30% energy savings in the mixed-humid
climate but is an important money and time-saving measure for more highly
efficient homes.
• Other details or specifications. Details and specifications should be written
or drawn to specify how particular measures will be installed, including both
the techniques and the materials to be used. Of particular importance are
specifications and details for items that differ from local standard practice
such as caulking; draft stops behind bathtubs, stairs, and dropped ceilings;
duct sealing requirements; gasket materials; window schedules specifying
U-factors and solar heat gain coefficients (SHGCs); and product performance
metrics. Also specify items that should not be done, such as caulking ceiling
penetrations under conditioned attics.
Plans — Keep Them Right
Best Practice: Avoid plan changes. When they are required, document the changes as
AVOID CHANGES
Thoroughly document
any changes to plans.
you would the original contract.
Numerous difficulties can be avoided with correct building plans. If the plans have
been properly developed, with the proper sizing of equipment, you must be sure that
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changes will not undo this good work. The practice of verbally communicating changes
is always risky and is potentially disastrous for a systems-designed home where highperformance features interact to achieve energy efficiency, comfort, and durability.
Before making any changes ask yourself these questions:
• Why are the changes being made? If there are no clear benefits from the
change, don’t do it.
• What effect will the change have on building performance? Will the change
deviate from best practice recommendations? Will you need to change HVAC
sizing or system selection? If you don’t know the answer to these questions, ask
your designer, engineer, or home energy rating system (HERS) professional.
Be sure to adjust all the systems related to the change.
• Are new drawings or specifications needed to clearly document your
expectations? Be clear in your expectations.
Contracts – Write Them Down
Best Practice: Prepare or update formal contracts with key subcontractors that clearly show
what you expect of them and what they can expect from other subcontractors. Relevant
details, plans, and specifications described in the last section should be referenced in the
contracts. If the subcontractor is providing materials, list the specific materials that you
want. Here are some examples of materials that a subcontractor may supply:
WORKING WITH
SUBCONTRACTORS
Always prepare formal
contracts and be clear
about your expectations.
• Recessed downlights, which should be air-tight and rated for insulation contact
• Water-based mastic, to seal ducts
• High-density fiberglass insulation
• Sealants and caulks to seal penetrations
• Windows which are typically ordered along with other major purchases, but if a
subcontractor is supplying them, be sure they are rated as called out in the plans
• Draft-stopping sheathing to seal large air leaks.
If you have expectations for a subcontractor, such as sealing certain types of holes,
or installing insulation in some space that may become inaccessible, be sure these
expectations are spelled out in the contract. The scope of work should cover things
like equipment size, duct sizes, identification of who is responsible for sealing which
holes, etc. Contract specifications and written assignments of responsibility can greatly
simplify the ordering of materials. Duct installers, for example, will know exactly what
kind of duct material will be used and how much; and with this knowledge may be able
to prefabricate many of their assemblies back at the shop, rather than in the field. These
pre-assembled pieces tend to be of higher quality thanks to the proximity of tools and
materials and better working conditions in the shop.
The Trades
chapter contains instructions that you may consider incorporating
into your contracts. Other sources of useful contracting tools include statements of
work that were developed by ConSol, one of the organizations that lead a Building
America team. Here is a partial listing of statements of work, designed for California,
that are available on the Web at www.comfortwise.com/installationprotocols.shtml or
at www.thebii.org/rpsw.asp:
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Site Supervisors
• Quality caulking and sealing
• HVAC system design and installation
• Quality installation of insulation
• Sliding door installation
• Window installation.
Pre-Construction Meeting – Have One
Best Practice: A final strategy to manage expectations among the subcontractors
is to hold a pre-construction meeting that includes as many of the subcontractors
as possible. At this meeting you can emphasize the changes in workflow, shifts in
responsibilities, and newly introduced building details. Tell your subcontractors about
your goals for energy-efficient houses.
PRE-CONSTRUCTION MEETING
Include your subcontractors in
pre-construction meeting to discuss
changes associated with your
energy efficiency goals.
Give the subcontractors drawings and instructions on how to accomplish their jobs.
Sample instructions are included in the Trades
chapter. This meeting will go a long
way toward helping people to understand their roles and responsibilities. Make sure
that your subcontractors are aware that you will be conducting inspections and that
both the ductwork and the building envelope will be tested for air tightness.
It may be necessary, especially when starting your first energy-efficient homes, to hold
additional training sessions with key subcontractors. More on this is discussed in the
Managing Quality section below.
Permits – Grease the Skids
A home built according to the instructions contained in this document for the mixedhumid climate does not violate any provisions of the national model codes or, usually,
of local regulations. However, many local code officials are unfamiliar with some of the
recommended construction techniques. It is well worth your while to raise these issues
yourself before construction begins so that you’re not surprised by a red tag later.
Best Practice: Ensuring that the “new” techniques are clearly delineated on the building
plans can also help flag these issues during plan review rather than during inspection.
Best Practice: A meeting with the building department before construction is well-
advised. Your code official may need information in support of the new techniques you
may use in an energy-efficient home.
Appendix III contains a sample of a draft code note that may be helpful. A set of draft
code notes is available on DOE’s Building Energy Codes Resource Center. These draft
documents are written for codes officials and provide a description of energy efficiency
techniques, citations to relevant codes, and guidance for plan reviews and field
inspections. The sample in Appendix III is the last one on the list below and is entitled
Rigid Board Insulation Installed as Draft Stop in Attic Kneewall – Code Notes (Draft).
Here is a list of available code notes that should help assure your local code official that
the proposed techniques are both safe and in compliance with the model codes; the
code notes are available at www.energycodes.gov/support/code_notes.stm.
Building America Best Practices Series: Volume 4 – Builders and Buyers Handbook for
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SHOW TECHNIQUES
ON BUILDING PLANS
Ensure that all “new” techniques
are delineated on the building plans.
PLAN A MEETING WITH THE
BUILDING DEPARTMENT
Your code official may need
information about energy-efficient
home techniques.
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Site Supervisors
•
Single top plate
•
No headers in nonbearing walls
•
Header hangers in bearing walls
•
Framing floor joists spaced at 24 inches on center
•
Framing studs spaced at 24 inches on center
•
Open spaces as return-air options
• Details for mechanically vented (conditioned) crawl spaces
• Ventilation requirements for condensing clothes dryers
•
Drywall clips
•
Rigid board insulation installed as draft stop in attic knee wall.
““There is an education aspect
both with the buyers and with
the trades people. A lot of
people do not really understand
the real benefits of building
to these Building America
principles.”
Michelle Horstemeyer, a lead
builder for John Wieland Homes
Managing Execution
If you’ve managed to establish clear expectations with your subcontractors and
suppliers, you’re almost ready to begin construction. The final parts of the plan involve
training subcontractors as necessary, scheduling everything, and monitoring progress.
Training
Best Practice: Attend and have your key subcontractors attend a training course on
systems-designed housing.
SYSTEM DESIGNED HOUSING
Be sure to attend a training
on systems-designed housing.
One good way to accomplish this may be to let your HERS provider (see Quality
Assurance below) conduct the necessary training. Information on general training is
available from
• Building America – www.buildingamerica.gov
• Energy and Environmental Building Association – www.eeba.org
• Building Science Corporation –www.buildingscience.com/workshops/default.htm
• National Association of Home Builders Research Center – www.nahbrc.org
• Southface Energy Institute – www.southface.org
• IBACOS – www.ibacos.com.
Other sources may include regional universities or Cooperative Extension Service
programs, homebuilder associations, utilities, and codes programs. More specialized
training is available at the above sources, plus trade organizations, such as:
• Air Conditioning Contractors Association – offers technician certification
– www.acca.org
• American Architectural Manufacturers Association – offers window
installation master certification – www.installationmastersusa.com.
The Web provides a free and easy method to train crews. The California Energy
Commission offers on its Web site a series of brief videos, lasting only a few minutes
each, that cover many installation processes. Visit www.energyvideos.com for access to
dozens of videos. The U.S. Department of Housing and Urban Development Pathnet
Web site contains videos on buildings systems and new plumbing technologies.
Visit www.pathnet.org/sp.asp?id=10787 to view PATH TV. PATH stands for the
Partnership for Advanced Housing Technology.
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Scheduling
Constructing an energy-efficient home requires careful attention to scheduling. Several
of the new construction techniques may require changing the order of subcontractors;
some require (or benefit from) a shifting of responsibilities from one subcontractor
to another; and some new activities will need to be added into the schedule. Here are
some of the more important schedule considerations:
• Schedule HVAC rough-in before plumbing and electrical. It is far more
important for the ductwork to have un-constricted access and pathways than
it is for wires or pipes. But be sure needs for other systems, such as drain pitch,
are coordinated.
• If using a conditioned attic, schedule insulating under the roof deck before
HVAC rough-in. The insulators must be able to do their job without
tromping on the carefully placed ductwork.
• Don’t forget to schedule for pipe insulation under the slab.
• Be sure to schedule pre-drywall insulation inspections, flashing inspections,
and envelope and duct pressure tests. Inspect at key points to ensure that
insulation and envelope sealing take place before areas become inaccessible.
Inspections are much more likely to happen if scheduled. And subcontractors
may be a bit more conscientious if they know their work will be evaluated.
• Be sure to schedule caulking of electrical and plumbing penetrations after
drywall is completed and the lines have been installed.
Some situations that may require a shifting of responsibilities include:
• If using advanced framing techniques that include two-stud corners and
floating drywall corners (see the section on wall framing in the Designers
chapter and Appendix III), someone must attach drywall clips. The framer
is a more likely candidate than the drywall installer for framing modifications.
Jeff Simon, Executive Vice
President of Operations for
Veridian Homes, offers this advice
for builders considering Building
America, “You need to have
systems in place for scheduling
and documentation so you can
successfully recreate the home.
If you don’t have good systems
and good organization, it will be a
challenge. You need to be willing
to take a risk.”
• Some caulking work needs to be done by the HVAC subcontractor. In
particular, main supply and return trunks that lead through walls need to
be caulked by the person connecting them to the equipment. Don’t let the
drywall finisher do this with mud—it is neither a good sealant nor durable
enough. Also, all duct terminations, including jump ducts, must be sealed
when registers are installed.
• Some post-finish caulking can be avoided by having the electrician use
pre-fabricated air-tight electrical boxes (see the Trades
chapter for an
electricians tip sheet).
• If installation of windows and drainage planes are done by different
subcontractors, the window installer must be careful to leave flashing
unattached at the bottom so that the first row of building paper may be tucked
under it (see the Trades
chapter tip sheets for window flashing, house
wrap, and sealants).
• If you are using insulated headers, the framer will need to install insulation
inside any double headers (using sandwiched foam insulation). Open headers
may be left for the insulation contractor.
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• Draft stops must be installed behind bathtubs and stairwells on exterior
framed walls. The framer should do this, but be sure that insulation is installed
before the draft-stop material goes on.
• Innovative scheduling of subcontractors can bring huge rewards in reduced
costs and improved quality. See our case study on Pulte Sun Lakes for
more information.
Quality Assurance
The NAHB, the U.S. Department of Housing and Urban Development, and other
sources of builder technical and management information offer guidance for improving
quality assurance on job sites. The following sections contain quality assurance
information related to energy efficiency.
“Building America is
a way to manage risk,
potential litigation issues,
and building systems
failures.”
Josh Robinson, Pulte Sun
Lakes project manager and
a Pulte Vice President
Inspections
Best Practice: Conduct several inspections during the course of construction, always
conduct pressure tests of both the whole house and the HVAC ductwork, and always check
AC and heat pump refrigerant charging. Have the house rated by a certified HERS rater.
INSPECTIONS
Conduct inspections throughout
the construction process.
Especially when energy-efficient systems-designed housing is new to your
subcontractors, you should conduct multiple inspections to ensure that the
subcontractors have understood what is required of them and how to implement it.
After the process has become more routine, you might get by with just a couple of
inspections. One key inspection should occur prior to installation of drywall.
The pre-drywall inspection allows you to ensure that insulation and draftstopping have
been properly installed before they get permanently enclosed. This is also the best time
to conduct a pressure test on the ductwork. The duct pressure test should be conducted
with the HVAC contractor present, at least for his or her first several energy-efficient
homes. If the ductwork fails to meet the pressure criteria, a smoke test will reveal the
worst leaks. It is crucial that this happen while the ductwork is still visible and the
HVAC contractor is present to see what the problem areas are.
Duct testing services can be most easily obtained through a certified HERS rater.
The rater can also conduct whole-house pressure tests and assist with training. And
the HERS rating itself can be a valuable marketing tool for an energy-efficient house.
To identify a certified rater in your area, check the registry at the Residential Energy
Services Network (RESNET) Web site: www.natresnet.org.
The second important inspection comes after completion of the home, including all
interior and exterior finishes. This pre-occupancy inspection should check for proper
sealing of electrical and plumbing (fixtures and drywall penetrations), HVAC registers,
and the HVAC closet. A whole-house air leakage test (aka “blower-door” test) is
crucial. Again, your HERS provider is the easiest resource for this service, and this is
when he or she would be rating the home anyway. Also, if your HVAC contractor has
not done it, a final check of the AC or heat pump refrigerant charge is crucial. Studies
have shown that failure to check refrigerant charging results in the average system using
13% too much energy (http://hem.dis.anl.gov/eehem/00/001105.html).
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Energy Efficiency Checklists
A successful energy-efficient building involves many details. It is worthwhile to
maintain for each house a checklist of important features to keep track of what has
been done. Although the best checklist is one you’ve made specific to the design(s) you
are implementing, the three checklists on the following pages are a good baseline to
work from and may be integrated with your existing checklists.
SPOT-CHECK INSPECTION CHECKLIST
These items should be checked if possible as they are installed because they may not be
accessible at the pre-drywall inspection.
Grading is sloped at 5% away from the house for at least 10 feet.
Roof drainage is directed at least 3 feet beyond the building.
A 6-mil polyethylene sheet is installed directly beneath the
concrete slab, continuously wrapping the slab and the grade beam.
Roof materials are installed to provide a continuous drainage
plane over the entire surface of the roof. Wall/roof junctures
should be appropriately flashed, including kick-out flashing
at the bottom.
HVAC system is appropriately sized and installed according
to plans. No deviations should be made in the field.
A mechanical ventilation system is installed as specified
in the plans.
Each bedroom has a separate HVAC return duct, a transfer
grille, or a jump duct.
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PRE-DRYWALL INSPECTION CHECKLIST
Note: Some measures in this list are unnecessary depending on whether the house is
sealed on the interior (e.g., air-tight drywall) or exterior (e.g., sheathing) of the wall.
Bathtubs on exterior walls have insulation behind them and
draftstops installed.
Dropped ceilings, dropped-soffit cabinets, and stairwells on
exterior walls have draftstops installed behind them (unless drywall
was installed prior to framing-in).
Windows and doors are sealed to framing using caulks, foams,
backer rod, and/or similar.
Window flashing is properly installed to shed water.
All electrical and plumbing penetrations between conditioned
and unconditioned spaces are caulked or otherwise sealed.
All recessed lights beneath unconditioned spaces are air-tight and
rated for insulated ceiling (IC). All kitchen and bathroom fans are
appropriately rated (capacity and sound) and exhausted to
the outside.
All exterior penetrations (exterior light fixtures, phone and other
service cables, etc.) are sealed with caulk, gaskets, or similar.
All housewrap seams are overlapped and taped; top and bottom
edges are sealed past the plates; housewrap is appropriately lapped
under window flashing.
Building paper seams are overlapped shingle style to shed water
and appropriately lapped under window flashing.
Batt insulation is kraft-faced or blown-in insulation or spray
foam is used.
Unless specifically required by code, no polyethylene vapor
retarder is installed on the inside of the walls.
Ductwork is sufficiently air-sealed as verified by a duct pressure
test conducted by a HERS rater or other qualified buidling
scientist. Ductwork leakage to the exterior should be not more
than 5% of the total air handling unit capacity (at high speed)
when tested at 25 Pa pressure.
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PRE-OCCUPANCY INSPECTION CHECKLIST
Entry of main supply/return ducts into air handling unit closet is
appropriately sealed with foam, caulk, or similar materials
(NOT with drywall mud).
Plumbing penetrations are air sealed.
Electrical switch and outlet boxes are sealed to drywall with
caulk or gaskets.
Light fixture boxes are sealed to drywall with caulk or gaskets.
Bathroom and kitchen fans are sealed to drywall with
caulk or gaskets.
Bathroom and kitchen fans are drawing air-tested with a small
piece of tissue; the fan should hold the paper against the grille.
Duct boots/registers are sealed to floor or drywall with
caulk or gaskets.
Attic hatches and kneewall entries are weatherstripped and insulated.
Refrigerant charge on air-conditioner/heat pump is verified in
writing by installer to be within specs, using superheat method
for non-Thermostatic Expansion Valve (TXV) systems or
subcooling method for TXV systems; this may require a return
visit during warm weather.
The whole-house envelope is sufficiently air-sealed as verified by a
whole-house pressure test. Air leakage should be tested by a HERS
rater and should be less than:
2.5 in.2 per 100 ft2 of envelope area (Canadian General Standards
Board (CGSB), calculated at a 10-Pa pressure differential), or
1.25 in.2 per 100 ft2 of envelope area (American Society for
Testing and Materials [ASTM], calculated at a 4-Pa pressure
differential), or
0.25 CFM/ft2 of envelope area when tested at a 50-Pa
pressure differential.
Building America Best Practices Series: Volume 4 – Builders and Buyers Handbook for
Improving New Home Efficiency, Comfort, and Durability in the Mixed-Humid Climate
Version 1, 9/2005 • SUP-10
Site Supervisors
Sources & Additional Information
(See Appendix V for more information on Web sites.)
• www.acca.com
• www.buildingamerica.gov
• www.buildingscience.com/workshops/default.htm
• www.comfortwise.com/installationprotocols.shtml
• www.eeba.org
• www.energycodes.gov/support/code_notes.stm
• www.energyvideos.com
• http://hem.dis.anl.gov/eehem/00/001105.html
• www.ibacos.com
• www.installationmastersusa.com
• www.nahbrc.org
• www.natresnet.org
• www.pathnet.org/sp.asp?id=10787
• www.southface.org
• www.thebii.org/rpsw.asp
Building America Best Practices Series: Volume 4 – Builders and Buyers Handbook for
Improving New Home Efficiency, Comfort, and Durability in the Mixed-Humid Climate
Version 1, 9/2005 • SUP-11
Trades
Professional tips for fast and easy installation
INTRODUCTION
On the following pages you will find step-by-step,
easy-to-follow illustrated instructions for implementing
key energy efficiency technologies.
These Building Tips are designed to be easily duplicated
and distributed.
• Slab Insulation - Mixed-Humid Climate
• Basement & Conditioned (Unvented) Crawlspace Insulation
• Housewrap
• Window Flashing
• Air Sealing - Plumbing
Taking action in
your community
HOMEOWNERS
Shopping for value,
comfort, and quality
MANAGERS
Putting building
science to work for
your bottom line
MARKETERS
Energy efficiency
delivers the value that
customers demand
• Air Sealing - Electrical
SITE PLANNERS
& DEVELOPERS
• Air Sealing - Drywall
Properly situated houses
pay big dividends
• Air Sealing - Glossary
• Fiberglass Insulation
• Masonry Construction
• Radiant Barriers
• Duct Sealing
DESIGNERS
Well-crafted designs
capture benefits for builders,
buyers, and business
SITE SUPERVISORS
Tools to help with
project management
TRADES
Professional tips for fast
and easy installation
CASE STUDIES
Bringing it all together
Building America Best Practices Series: Volume 4 – Builders and Buyers Handbook for
Improving New Home Efficiency, Comfort, and Durability in the Mixed-Humid Climate
Version 1, 9/2005 • TRD-1
Slab Insulation
Mixed-Humid Climate
Building Tips
* Slab insulation may not be needed to reach energy
efficiency targets of these best practices
= Sealant or Gasket
Roof flashing
Optional blower
Radon reduction
3" plastic pipe vent stack
Cover insulation
exposed above grade
Hold drywall
1/2” above floor
Perforated
drain pipe
(see list on reverse)
Use extruded (R-5 per inch)
or expanded (R-4 per inch)
polystyrene or rigid
fiberglass insulation
Seal all slab
penetrations
Rigid foam insulation
(extends under entire slab
and replaces polyethylene
vapor retarder)
(also serves as
capillary break)
Metal termite
flashing
Concrete
slab
Gravel base
Damp proofing
(4-6" deep coarse, no fines)
Damp proofing
Sill gasket
membrane
Polyethylene vapor diffusion retarder
Polyethylene or damp proofing capillary break
Perforated drainage
pipe embedded
in gravel
Concrete footing below frost depth
EXTERIOR INSULATION
PACKAGE
INTERIOR INSULATION
FOR FLOATING SLAB
Rigid insulation
extends horizontally 2’
Cover insulation
exposed above grade
(see list on reverse)
Damp proofing
6 Mil. Polyethylene
vapor diffusion retarder
(extends under grade beam
acting as a capillary break)
Rigid insulation
extends horizontally
(horizontal distance
equivalent to frost depth)
SHALLOW FROST-PROTECTED
FOUNDATION
(get code approval before proceeding)
See more information on the following page.
Building America Best Practices Series: Volume 4 – Builders and Buyers Handbook for
Improving New Home Efficiency, Comfort, and Durability in the Mixed-Humid Climate
Version 1, 9/2005 • TRD-2
Building Tips: Slab Insulation - Mixed-Humid Climate
Slab Foundation System Moisture and Air Leakage Control
• Keep all untreated wood materials away
from contact with earth and concrete.
• Design the house structure with
overhangs, gutters, drainage planes,
and flashing to shed rainwater and
conduct it away from the house.
• Slope the earth away from the house
and ensure that no irrigation strikes
near the foundation.
• Use a sill gasket for air sealing
• Install a protective shield such as
metal flashing, plastic L bracket, or
a membrane (such as EPDM flexible
roofing material*) to block capillary
water wicking into the wall from the
foundation. The protective shield may
also serve as a termite shield.
• Slabs require a foundation drain where • Note that some code jurisdictions
the slab (or floor) is located below
may require a gap between exterior
grade. Install a foundation drain
insulation and wood foundation
alongside the footing (not above it).
elements to provide a termite
The drain should rest in a bed of coarse
inspection area.
gravel (no fines) that slopes away from
• Install damp proofing or a
the foundation and is covered with
polyethylene sheet over the footing
filter fabric.
to block capillary water wicking into
• Exterior rigid fiberglass insulation
the foundation side wall.
may provide a drainage plane that will
• Install a capillary break and vapor
channel water to the foundation drain
retarder under the entire slab consisting
and relieve hydrostatic pressure.
of at least a 6-mil polyethylene sheet
• Exterior foundation wall insulation
or continuous rigid foam insulation
requires a protective coating at
approved for below grade applications,
above-grade applications. Examples
on top of 4 to 6 inches of coarse gravel.
of protective coverings for exterior,
• Install radon control measures
above-grade insulation include
(check local requirements and EPA
flashing, fiber-cement board, parging
recommendations).
(stucco type material), treated
plywood, or membrane material
*EPDM stands for Ethylene Propylene Diene Monomer.
(EPDM* flexible roofing).
Sources & Additional Information
•
U.S. DOE, Technology Fact Sheet on Slab Insulation (www.eere.energy.gov/buildings/documents/pdfs/29237.pdf).
•
U.S. EPA, Building Radon Out: A Step-By-Step Guide oni How to Build Radon Resistent Homes (www.epa.gov/199/iaq/radon).
•
Southface Energy Institute. Fact Sheets #29: Insulating Foundation and Doors
(www.southface.org/home/sfpubs/techshts/29_insulatefloors4PDF.pdf).
•
Southface Energy Institute. Fact Sheets #30: Radon-Resistant Construction for Builders
(www.southface.org/home/sfpubs/techshts/30_radonresistantconst.pdf).
•
Building Science Consortium. Introduction to Building Systems Performance: Houses that Work II. www.buildingscience.gov
Building America Best Practices Series: Volume 4 – Builders and Buyers Handbook for
Improving New Home Efficiency, Comfort, and Durability in the Mixed-Humid Climate
Version 1, 9/2005 • TRD-3
Basement & Conditioned (Unvented)
Crawlspace Insualtion
Building Tips
EXTERIOR CRAWLSPACE INSULATION
INTERIOR CRAWLSPACE INSULATION
= Sealant or Gasket
Rigid insulation
Rigid Insulation
Sill gasket membrane
Treated
wood nailer
Cavity insulation
(also serves as capillary break)
Damp proofing
Metal termite flashing
Cover insulation
exposed above grade
Continuous
polyethylene
Polyethylene or
damp proofing
capillary break
Treated wood nailer
(bring vapor barrier
up to grade level)
Rigid fiberglass insulation
Polyethylene vapor barrier
Rigid insulation
Polyethylene or damp
proofing capillary break
Damp proofing
Rigid insulation
Perforated drainage
pipe embedded in
coarse gravel
Damp proofing
Continuous
polyethylene
Concrete footing
below frost depth
EXTERIOR BASEMENT INSULATION
Polyethylene or
damp proofing
capillary break
If depth does not extend two feet below grade, place
remaining insulation horizontally along the ground.
Radon reduction
3” plastic vent pipe
INTERIOR BASEMENT INSULATION
Sill gasket membrane
(also serves as capillary break)
Cavity insulation
Metal termite flashing
Cover insulation
exposed above grade
Rigid fiberglass insulation
Polyethylene or damp
proofing capillary Break
Cavity
insulation
Damp proofing
Polyethylene vapor
diffusion retarder
Damp proofing
Polyethylene or
damp proofing
capillary break
Rigid insulation
with foil facing
Perforated drainage
pipe embedded in
coarse gravel
Concrete footing
below frost depth
See more information on the following page.
Building America Best Practices Series: Volume 4 – Builders and Buyers Handbook for
Improving New Home Efficiency, Comfort, and Durability in the Mixed-Humid Climate
Version 1, 9/2005 • TRD-4
Building Tips: Basement & Conditioned Crawlspace Insulation
Installation Tips
• Exterior and interior insulation approaches may be combined to provide needed insulation levels.
• Properly installed exterior rigid fiberglass insulation provides the best moisture management properties of the available insulation types.
• Interior nailing strips for finished walls should be installed over rigid foam (extruded polystyrene is more moisture tolerant
than expanded polystyrene) insulation so that the foam is sandwiched between the nailing strip and the basement wall.
• Seal joints with adhesive or mastic on interior foam insulation applied directly to foundation walls.
• If interior blanket or batt insulation is used, it should be combined with exterior or interior rigid insulation attached
directly to the foundation wall. The blanket or batt insulation should be unfaced or have a facing that allows moisture
to pass through, and should be used in a conditioned basement. The drywall should be tightly air sealed to keep interior
moist air from condensing on the foundation wall.
• Foil-faced rigid insulation is a good interior insulation choice for unfinished basements.
Crawlspace and Basement Foundation System Moisture and Air Leakage Control
• Keep all untreated wood materials away
from contact with earth and concrete.
• Design the house structure with
overhangs, gutters, drainage planes, and
flashing to shed rainwater and conduct it
away from the house.
• Slope the earth away from the house
and ensure that no irrigation strikes
near the foundation.
• Damp-proof all below grade portions of
the exterior foundation wall to prevent
the absorption of ground water.
• Use a sill gasket for air sealing
• Install a protective shield such as
metal flashing, plastic L bracket, or
a membrane (such as EPDM flexible
roofing material*) to block capillary
water wicking into the wall from the
foundation. The protective shield may
also serve as a termite shield.
• Crawlspaces require a foundation drain • Note that some code jurisdictions
when the crawlspace floor is located
may require a gap between exterior
below grade. Always install a foundation
insulation and wood foundation
drain in basements. Install a foundation
elements to provide a termite
drain alongside the footing (not above
inspection area.
it). The drain should rest in a bed of
• Install damp proofing or a polyethylene
coarse gravel (no fines) that slopes away
sheet over the footing to block capillary
from the foundation and is covered with
water wicking into the foundation
filter fabric.
side wall.
• Exterior rigid fiberglass insulation
• Install a capillary break and vapor
may provide a drainage plane that will
retarder under slabs and basement
channel water to the foundation drain
floors consisting of at least a 6-mil
and relieve hydrostatic pressure.
polyethylene sheet or continuous rigid
• Exterior foundation wall insulation
foam insulation approved for below
requires a protective coating at
grade applications, on top of 4 to 6
above-grade applications. Examples
inches of coarse gravel.
of protective coverings for exterior,
• Install radon control measures
above-grade insulation include
(check local requirements and EPA
flashing, fiber-cement board, parging
recommendations).
(stucco type material), treated
plywood, or membrane material
*EPDM stands for Ethylene Propylene Diene Monomer.
(EPDM* flexible roofing).
Sources & Additional Information
• IBACOS. 2002. Consider the Crawlspace (www.buildingamerica.gov)
• IBACOS. 2002. Don’t Forget About the Basement (www.buildingamerica.gov)
• Lstiburek, Joseph. 2004. Builders Guide to Cold Climates (www.eeba.org/bookstore)
• U.S. DOE, Technology Fact Sheet: Basement Insulation (www.buildingamerica.gov)
• U.S. DOE, Technology Fact Sheet: Crawlspace Insulation (www.buildingamerica.gov)
• U.S. EPA, Building Radon Out: A Step-By-Step Guide on How to Build Radon Resistent Homes
(www.epa.gov/1999/iaq/radon)
• Yost and Lstiburek. 2002. Basement Insulation Systems (www.buildingamerica.gov)
Building America Best Practices Series: Volume 4 – Builders and Buyers Handbook for
Improving New Home Efficiency, Comfort, and Durability in the Mixed-Humid Climate
Version 1, 9/2005 • TRD-5
Housewrap
Building Tips
Minimize cuts in housewrap and caulk or tape to seal all penetrations
Tape housewrap according to manufacturers specifications at top plate,
band joist, and horizontal seams, and secure with plastic-capped nails
Housewrap
Plastic-capped Nails
P
RA
US
US
HO
Fasten flaps of window "T-cut"
to the inside of the framing.
HO
US
EW
HO
RA
P
Seal floodlight
at opening
EW
EW
RA
P
Unroll around house
US
P
RA
EW
US
K
K
US
HO
HO
HO
US
EW
RA
P
US
EW
RA
P
Housewrap Tape
EW
RA
P
UL
UL
HO
CA
EW
H OR A P
US
EW
RA
P
(* See Window Flashing Building Tips)
HO
HO
EW
US
HO
RA
CA
EW
HO
P
US
U
P
US
O
RA
US
RA
RA
EW
DOW
WIN
HO
H
W
SE
EW
RA
P
K
P
Sheathing
UL
P
CA
Seal spigot
at opening
Caulk under housewrap
and seal gap between
electrical box and
sheathing
Caulk
Housewrap
Housewrap should
be overlapped shingle-style
Seal overlap with tape
Seal housewrap to foundation
below bottom plate in basement
or crawlspace.
Sill Gasket
Tape
= Another trade may have completed this step. Confirm with the site
supervisor. If not, and you need to complete the step yourself, ensure
that the necessary materials are available on site.
Sources & Additional Information
•
Southface Energy Institute. Fact Sheets #8 Air Sealing (www.southface.org/home/sfpubs/techshts/8_airsealing.pdf)
•
U.S. DOE. Technology Fact Sheet on Air Sealing (www.eere.energy.gov/buildings/documents/pdfs/26448.pdf).
•
See also the Building Tips on Air Sealing and Window Flashing
•
See: http://construction.tyvek.com/en/productServices/HomeWrap/index.shtml
•
Straube, John. 2001. Canadian Architect. “Wrapping it Up”. May, 2001. www.cdnarchitect.com.
Building America Best Practices Series: Volume 4 – Builders and Buyers Handbook for
Improving New Home Efficiency, Comfort, and Durability in the Mixed-Humid Climate
Version 1, 9/2005 • TRD-6
Window Flashing
Building Tips
Example of window flashing details for home with housewrap and plywood or OSB wall sheathing.
STEP 1- If Housewrap Has Not Been Installed
STEP 1- If Housewrap Has Been Installed
HO
Cap Nails
HO
>10"
U
HO
SE
W
RA
P
U
W
SE
RA
SE
W
R
R
U
HO
AP
H
P
S
OU
EW
RA
HO
US
EW
SE
W
RA
P
P
H
>12"
p
P
RA
ewra
W
SE
Hous
U
O
S
OU
EW
RA
P
HO
P
RA
H
EW
EW
6"
45˚
OU
US
H
S
OU
EW
RA
US
P
P
RA
H
S
OU
EW
RA
P
Apply at least a 12-inch flap, or apron, of building paper
or housewrap just below the windows sill.
Cut the housewrap covering the rough opening in the
shape of a modified "Y."
If the window sill is close to the sill plate, the apron
can extend all the way to the sill plate.
Fold the side and bottom flaps into the window
opening and secure.
The apron should extend at least 10 inches past the sides of the
window opening, or to the first stud in open wall construction.
Above the window opening, cut a head flap and
flip up to expose sheathing, and loosely tape in place
out of the way.
Attach only the apron’s top edge with cap nails.
STEP 2 - Sill Flashing
HO
U
W
SE
RA
STEP 3 - Jamb Caulking
P
HO
6"
E
US
W
RA
HO
U
W
SE
RA
HO
CA
Tape E W R
HO
U
SE
Self-adhesive
P
RA
Window
Flashing
W
HO
UL
AP
US
Install self-adhesive flashing to the sill, ensuring that
flashing extends up jambs at least 6 inches.
One commercial product comes with two removable strips
over the adhesive. Remove the first strip to expose half the
adhesive and apply this area to the sill. Begin pressing in the
middle of the sill and work towards the sides. Remove the
second strip to expose the adhesive that will be used to apply
the flashing below the window to the outside wall.
P
HO
US
EW
E
US
W
RA
K
RA
P
HO
U
W
SE
RA
P
Caulk the outside edges of the head and side jambs
Do not caulk across the sill
Install the window using corrosion-resistant nails and
following manufacturer's specifications.
Tape down the bottom corners of the flashing
Building America Best Practices Series: Volume 4 – Builders and Buyers Handbook for
Improving New Home Efficiency, Comfort, and Durability in the Mixed-Humid Climate
Version 1, 9/2005 • TRD-7
Building Tips: Window Flashing
STEP 4 - Jamb and Head Flashing
SE
W
STEP 5 - Seal Rough Opening Gap
R
OU
Fold HDown
Head Flap
1"
4"
H
S
OU
P
Self-adhesive
RA
W
S EHead Flashing
U
O
HO
Self-adhesive
Jamb Flashing
HO
US
EW
RA
US
EW
RA
P
CA
EW
R
HO
SE
W
RA
K
AP
P
U
HO
UL
US
P
Install self-adhesive jamb flashing extending 4 inches above the top
of the head flange and even with the bottom of the sill flashing.
Install self-adhesive head flashing extending 1 inch beyond
the jamb flashing.
On the interior side of the window, seal gap
between the window and the rough opening with
appropriate sealant.
If housewrap has been installed, be sure that the head flap,
when it is folded down, will cover the top of the flashing.
STEP 6 - If Apron was Installed
HO
HO
U
W
SE
RA
E
US
W
RA
P
HO
P
HO
Housewrap
secured to WRAP
E
US
windowHOflange
with tape
U
HO
SE
W
RA
STEP 6 - If Head Flap was Created
US
EW
RA
HO
P
Existing
Apron
HO
U
W
SE
RA
US
E
Head flap
secured with tape
P
HO
US
EW
R
U
W
SE
AP
Tape the edges where the housewrap meets the window flange
if housewrap is installed after flashing.
If building paper is used, embed the edges in a bead of sealant
where the paper meets the window flange.
P
H
P
If an apron was installed under the window, slip the housewrap
or building paper under the apron.
RA
HO
US
EW
RA
S
OU
EW
P
If headflap was created, fold it over the head flashing
and tape across the top window flange and the
45o angle seams.
Sources & Additional Information
•
•
•
•
Lstiburek, J.W. (2002). Water Management Guide. Minneapolis, MN: Energy and Environmental Building Association
(ww.eeba.org).
U.S. DOE Technology Fact Sheet on Weather-Resistive Barriers
(www.eere.energy.gov/buildings/documents/pdfs/28600.pdf).
Standard Practice for Installation of Exterior Windows, Doors, and Skylights. ASTM E2112-01, September 2002.
West Conshohocken, PA.
www.ibacos.com/ghome/Jan03/jan03_windows.html
Building America Best Practices Series: Volume 4 – Builders and Buyers Handbook for
Improving New Home Efficiency, Comfort, and Durability in the Mixed-Humid Climate
Version 1, 9/2005 • TRD-8
Air Sealing - Plumbing
Building Tips
Seal all plumbing and electrical penetrations.
Wall
Top Plate
Staples
Prefabricated roof-vent pipe flashing can be adapted as air sealing gaskets.
Vent pipe may be eliminated with an air-admittance valve in some jurisdictions.
CA
UL
K
Plumbing
Vent
Caulk/
Sealant
Insulate and airseal behind tub.
Blocking
Sealant between
gasket and plate
Thin sheet
goods as draft
stop behind tub
or enclosure
Caulk/sealant
Draft Stop
Ex
ter
Draft stop behind enclosure.
ior
Another trade may have
completed this step.
Confirm with the site
supervisor. If not, and
you need to complete
the step yourself, ensure
that the necessary
materials are available
on site.
Continuous bead
of sealant or
adhesive
Wa
ll
Keep pipes out of exterior walls and seal
penetrations through floor.
Seal penetrations through rim joists.
Be careful not to compress or disrupt floor
insulation, if it is present, keeping pipe runs
parallel and close to studs leaving more room
for insulation.
Exterior Wall
Rim
Joist
Insulate pipes
exposed to
unconditioned
areas
Seal tub penetration
Pipe
Floor Insulation
Sources & Additional Information
•
Lstiburek, J. W. 2000. Builders Guides. Minneapolis, MN. Energy and Environmental Building Association. www.eeba.org.
•
U.S. DOE Technology Fact Sheet on Air Sealing (www.eere.energy.gov/buildings/documents/pdfs/26448.pdf).
•
www.toolbase.org: click on New Building Technology > Plumbing > Distribution Systems > Air Admittance Vents
Building America Best Practices Series: Volume 4 – Builders and Buyers Handbook for
Improving New Home Efficiency, Comfort, and Durability in the Mixed-Humid Climate
Version 1, 9/2005 • TRD-9
Electrical Air Sealing
Building Tips
Recessed light fixtures should be rated for Insulated Ceiling Air Tight (ICAT).
Airtight Wire
Connection From
Junction Box
Ceiling fans should be wired to a wall switch.
AIRTIGHTNESS LABEL
Seal light fixture boxes to drywall with caulk or foam.
AIR TIGHTNESS
LABEL
Caulk
Seal bath fan box to drywall
with caulk or foam.
Seal Wire
Connection
Airtight Can
Sealant
Seal all exterior penetrations, such as
porch light fixtures, phone, security,
cable and electric service holes, with
caulk, spray foam, or gaskets - note
that foam degrades in sunlight.
Electrica
l
Panel
Decorative
Cover
Suppo
rt Shea
Use air-tight outlet boxes
or seal standard boxes.
thing
K
UL
CA
Nailing
Flange
Run wiring
along side
of stud at
exterior wall
and along
plates
Built-in
Sealant
Air Sealed
Electrical Box
Built-in
Gasket
Flange for sealing to
drywall air barrier
Seal standard plastic
electrical box at face
to drywall with joint
compound or cover
the plate gasket
with caulked foam.
Caulk at wire
penetrations
LK
CAU
EXTER
IOR W
ALL
Caulk/seal/foam all electrical wires penetrating
top and bottom plates of exterior walls.
Run wiring along bottom plate at exterior wall.
Standard Plastic
Electrical Box
Caulk
NOTE: Some codes require wires to be held up from
bottom plates 6"-8" to protect from future drilling through plates.
Sources & Additional Information
•
Lstiburek, J.W. 2000. Builder Guide Hot-Humid Climates. Minneapolis, MN: Energy and Environmental Building
Association (ww.eeba.org).
•
U.S. DOE. Technology Fact Sheet on Air Sealing (www.eere.energy.gov/buildings/documents/pdfs/26448.pdf).
•
See also Air Sealing Building Tips in the chapter.
Building America Best Practices Series: Volume 4 – Builders and Buyers Handbook for
Improving New Home Efficiency, Comfort, and Durability in the Mixed-Humid Climate
Version 1, 9/2005 • TRD-10
Air Sealing Drywall
WINDOW
INSTALLER
PLUMBER
DRYWALLER
ELECTRICIAN
MEASURE
*Actual assignments to be made by site
supervisor. The supervisor may choose to
work with a sealing specialist instead.
FRAMER
Building Tips
EXTERIOR WALLS
Install gaskets or caulk at top and bottom plates of exterior walls.

Seal between the bottom plate and subflooring.

Install gaskets behind coverplates.
 
Seal large holes behind bathtubs or stairs with sheathing.
 
PARTITION WALLS
Seal the drywall at the intersection with the top or bottom plate.

Seal penetrations through the top and bottom plates for plumbing, wiring,
and ducts using fire-resistant sealants.
Knee walls can be insulated and sealed at either the roofline or along the line formed by the
roof, wall, and floor. Rigid foam insulation, taped at the seams with housewrap tape, can be
used to seal the backside of the knee wall and the underside of the roof. Sealing along the
roofline is preferred in new construction.




WINDOWS & DOORS
Caulk or glue drywall edges to either framing or jambs.

Fill rough opening with foam backer rod and caulk (preferred) or low-expanding foam sealant.

Caulk window and door trim to drywall with clear or paintable sealant.


CEILING
Seal the junction between the ceiling and walls.

Whenever possible, use continuous drywall sheets for the ceiling
and walls to minimize joints to be sealed.

Seal all penetrations in the ceiling for wiring, plumbing, ducts, and attic access openings.
Building America Best Practices Series: Volume 4 – Builders and Buyers Handbook for
Improving New Home Efficiency, Comfort, and Durability in the Mixed-Humid Climate
  
Version 1, 9/2005 • TRD-11
Air Sealing Glossary
Building Tips
Caulk
Sheet Goods
Seals gaps of less than 1/2 inch. Select grade (interior,
exterior, high temperature) based on application.
(Plywood, Drywall, Rigid Foam Insulation) These
materials form an air retarder. Air leaks only at unsealed
seams or penetrations.
Expanding Spray Foam
Fills large cracks and small holes. Expanding foams are
messy but useful for filling large holes or cracks. The
material expands 2 to 3 times in volume after application.
It comes in one-part cans that require no mixing or in
two-part systems for larger jobs. It degrades in sunlight
and users should be careful not to get the foam on their
skin. DO NOT USE near flammable applications (e.g.,
flue vents). DO NOT USE on windows and doors.
In large applications, a two-part system is used, which
involves mixing the sealant on site. For small jobs, onepart spray cans are used.
Sheet Metal
Low-Expanding/Non-Expanding Spray Foam
Weatherstripping
These latex-based spray foams come in one-part spray
cans. They expand very little or not at all and will not
pinch jambs or void window treatments.
Used with high-temperature caulk for sealing hightemperature components, such as flues, chimneys,
and framing.
Polyethylene Plastic
This inexpensive material for air sealing also stops vapor
diffusion. All edges and penetrations must be completely
sealed for an effective air retarder. Poly is fragile, and
proper placement is climate specific.
Used to seal moveable components, such as doors,
windows, and attic accesses.
Mastic
Backer Rod
Closed-cell foam or rope caulk. Press into crack or gap
with screwdriver or putty knife. Often used with caulk
around window and door rough openings.
A thick paste that can be used on all duct materials that
provides a permanent seal. Seals air handlers and all duct
connections and joints. UL-181-approved water-based
mastic is best.
Gaskets
UL-181 or Foil-Faced Tape
Apply under the bottom plate before an exterior wall is
raised or use to seal drywall to framing instead of caulk
or adhesive.
Tapes approved for ducts and air handlers. Temporarily
seals the air handler.
Housewrap
Installed over exterior sheathing. Must be sealed with
housewrap tape or caulk to act as an air retarder.
Resists water, but is NOT a vapor barrier.
Sources & Additional Information
•
U.S. DOE. Technology Fact Sheet on Air Sealing (www.eere.energy.gov/buildings/documents/pdfs/26448.pdf).
Building America Best Practices Series: Volume 4 – Builders and Buyers Handbook for
Improving New Home Efficiency, Comfort, and Durability in the Mixed-Humid Climate
Version 1, 9/2005 • TRD-12
Fiberglass Insulation
Building Tips
INSTALLING FIBERGLASS BATT INSULATION
ALWAYS:
Avoid gaps, tight turns, and compression
•
Cut insulation to fit snugly in non-standard spaces.
•
Slit batts to fit around wiring and plumbing.
•
Notch out around electrical boxes and use scraps
to fill in behind.
Install long runs first – then use scraps to fill in
smaller spaces and gaps.
Use unfaced batts in hot and humid climates.
Even if blown-in insulation is to be generally applied,
use fiberglass batts to insulate areas that will be
inaccessible to the blown-in insulation, such as
behind bath enclosures.
Walls:
Ceilings:
Insulate and seal the attic access door
Install insulation over ICAT-rated recessed cans.
Verify ventilation pathways.
Install insulation baffles.
Band Joists:
Place insulation in the cavities between
joists and subfloor.
Caulk bottom plate to subfloor.
Caulk band joist to subfloor and plates and insulate.
Caulk bottom plate to subfloor.
Under Floor Insulation:
Friction-fit the batts in place until covered by drywall
or sheathing.
Metal stays, lathe, or stainless steal wire support
insulation in joist cavities.
Insulate before installing stairs and tubs and other
features that will block access.
In new construction it is preferred that crawlspace
walls are insulated. If underfloor insulation is to be
used, it can be held in place with metal staves, lathe,
stainless steel wire, or twine.
Knee Walls:
Seal knee wall to create a continuous air barrier. Knee
walls can be sealed following the wall itself and attic
floor or along the sloping edge of the attic roof. Rigid
foam insulation, taped at the seams with housewrap
tape, can be used to seal the backside of the kneewall
and the underside of the roof. Sealing along the
roofline is preferred in new construction.
Insulate and air seal the rafter space along the sloping
ceiling of the knee wall attic space or insulate and air
seal the roofline wall and floor.
Rafters should receive R-19 or R-30 insulation.
Cover rafters with a sealed air barrier (such as drywall
or foil-faced hardboard).
If truss systems are used under floors, an approach
better than batt insulation is to install netting or rigid
insulation to the underside of the floor trusses and fill
the joist cavity with blown-in insulation.
Sources & Additional Information
• Energy Efficient Building Association’s Builder’s Guide
Hot-Humid Climates, 2000.
•
U.S. DOE Technology Fact Sheet on Attic Access.
•
U.S. DOE Technology Fact Sheet on Crawlspace Insulation.
*
Refer to the Air Sealing Building Tips in this chapter
Caulk the barrier to the top plate of the wall below the
attic space and to the top plate of the knee wall itself.
Seal all other cracks and holes.
Building America Best Practices Series: Volume 4 – Builders and Buyers Handbook for
Improving New Home Efficiency, Comfort, and Durability in the Mixed-Humid Climate
Version 1, 9/2005 • TRD-13
Masonry Construction
Building Tips
Semi-vapor permeable rigid insulations used on the interior
of wall assemblies should be unfaced or faced with permeable
skins. Foil facings and polypropylene skins should be avoided.
Wood furring should be installed over rigid insulation; the
rigid insulation should be continuous over the surface of the wall,
except for the 2x4 furring near the ceiling. This blocking attaches
directly to the masonry block and is above the insulation, not behind it.
WINDOW SILL DRAINAGE
Wood Sub-Jamb
(Positioned Toward Wall Exterior So That
Face Of Interior Window Frame Is Flush With
Center Point Of Rib In Precast Masonry Sill)
Continuous 2x4 or 2x2 Horizontal Furring
Sealant between
masonry opening and
treated wood sub-jamb
(acting as draft or fire stop; seal all
service/wiring penetrations)
Interior Gypsum Board with
permeable or semi-permeable finish
Treated Wood
Sub-Jamb
Mounting Member
("back-caulked")
Masonry
Wall
Sealant forming
end dam
Semi-Permeable Rigid Insulation
(Expanded Polystyrene, Extruded Polystyrene,
Fiber-faced Isocyanurate)
Source: EEBA 9.5
Wood Furring
Gypsum Board
Sloping Precast Masonry
Sill with Precast Rib
Treated Wood Spacer/Mounting
Block to support window
Latex Paint or other permeable or
semi-permeable interior finish
Masonry Wall
Rigid Insulation
(Minimum 1/2" Thick)
Concrete
Slab
Wood Furring
(Minimum 3/4" Thick)
Gypsum Board
Source: EEBA 9.1
Shallow Electrical Box
(surface-mounted On
Masonry Interior)
Electrical boxes can be surface-mounted
eliminating chiseling/chipping masonry
Source: EEBA 9.7
ELECTRICAL BOX
Sources & Additional Information
•
Lstiburek, J. W. 2000. Builders Guides. Minneapolis, MN. Energy and Environmental Building Association. www.eeba.org.
Building America Best Practices Series: Volume 4 – Builders and Buyers Handbook for
Improving New Home Efficiency, Comfort, and Durability in the Mixed-Humid Climate
Version 1, 9/2005 • TRD-14
Radiant Barriers
Building Tips
Radiant Barrier
*foil-face down*
If installed before roof sheathing, drape the radiant barrier
foil-face down between the roof rafters.
If installed after roof sheathing,
install from inside the attic by
stapling the radiant barrier to
the bottom of the rafters.
Roof Rafters
BEFORE ROOF SHEATHING
Roof Sheathing
Radiant Barrier
*foil-face down*
AFTER ROOF SHEATHING
1"
Air
Space
NOTE: Some roof sheathing products have a radiant barrier
preinstalled; in this case, ensure the shiny side faces the attic.
Allow the material to droop between
attachment points to make at least a
1-inch air space between the radiant
barrier and the bottom of the roof.
Sources & Additional Information
•
U.S. DOE. EREC Brief on Radiant Barriers (www.eere.energy.gov/consumerinfo/refbriefs/bc7.html).
•
Southface Energy Institute. Fact Sheet #14 Radiant Barriers (www.southface.org/home/sfpubs/techshts/14radiantbarriers.pdf).
•
Southface Energy Institute. Fact Sheet #25 Ceiling and Attic Insulation and Ventilation
(www.southface.org/home/sfpubs/techshts/25_insulateceilings_4pdf.pdf).
Building America Best Practices Series: Volume 4 – Builders and Buyers Handbook for
Improving New Home Efficiency, Comfort, and Durability in the Mixed-Humid Climate
Version 1, 9/2005 • TRD-15
Duct Sealing
Building Tips
AIR HANDLER
SUPPLY & RETURN PLENUMS
Mastic collars to
metal plenum on
inside or outside
Mastic or caulk
Mastic
Mastic
Collar with strap;
mastic on take-off
Mastic all corners
of metal plenums
Mastic plenum
to air handler
SUPPLY
Mastic
Mastic to seal
refrigerant and
condensate line
Mastic or tape
exterior of duct board
Mastic
RETURN
Mastic exterior of collars
Mastic or caulk
Filter Rack
FLEX DUCT
BOOTS
Use wide straps to support flex duct
spaced at 5-foot intervals
Strap inner liner and
outer insulation
REGISTER
Seal
joints
in boots
Mastic
boot seams
Mastic before
attaching flex
duct
Run lines straight
using metal elbows at
bends and corners
Seal boots to sheet goods (drywall/subfloor)
with caulk, mastic or spray foam
Seal metal or flex to boot or elbow
and joints in elbow with mastic
Never puncture inner liner. If repair is
needed; install a coupling and seal properly
Mastic is a gooey adhesive that is applied wet. It fills gaps and dries to a soft solid. Mastics may or may
not contain reinforcing fibers, and they may be used with reinforcing mesh tape.
Sources & Additional Information
•
•
•
•
Energy Efficient Building Association Builder’s Guide Hot and Humid Climates, 2000.
Southface Energy Institute. Fact Sheet #2 Ductwork Questions & Answers
(www.southface.org/home/sfpubs/techshts/2duct_q&a.pdf).
Southface Energy Institute. Fact Sheet #18 Energy Checklist (www.southface.org/home/sfpubs/techshts/checklist.pdf).
www.ibacos.com/ghome/Oct03/bpflexduct.html
*
Diagrams courtesy of Southface Energy Institute Fact Sheet #2 Ductwork Questions & Answers.
Building America Best Practices Series: Volume 4 – Builders and Buyers Handbook for
Improving New Home Efficiency, Comfort, and Durability in the Mixed-Humid Climate
Version 1, 9/2005 • TRD-16
Ideal Homes
Norman, Oklahoma
INTRODUCTION
Building America helps Oklahoma Builder Outshine the Competition
In the 1990s, when Ideal Homes, a
builder of homes for first-time and firsttime move-up buyers in Oklahoma,
wanted to differentiate itself from
the competition, it turned to energy
efficiency, building first to ENERGY
STAR standards and then adopting the
Building America approach.
The move has been a win-win for
Ideal and its customers.
Home buyers get houses that are
at least 30% more energy efficient
than standard built homes.
Taking action in
your community
HOMEOWNERS
Shopping for value,
comfort, and quality
MANAGERS
Putting building
science to work for
your bottom line
“ The one thing that Building America
introduced into our market place that was
absolutely almost nonexistent in any price
point home was a higher quality window.”
Vernon McKown, Vice President of Ideal Homes,
And Ideal, which is Oklahoma’s
which builds 500 first-time homes a year in
biggest builder – completing 500
Oklahoma. McKown noted that many builders still
homes a year, is earning gross profit
use aluminum frame windows and home owners end
margins of 32%, according to Vernon
up with ice on the inside of their window frames in
McKown, the co-owner and vice
the winter—not a problem in Ideal’s homes, which
president of Ideal. “We charge on
are all built to Building America standards.
average $5,000 to $10,000 more than
our direct competitors for the same sized house on the same size lot,” said McKown, a
price increase buyers are willing to pay because they feel they are getting a better built
house. McKown estimates that the energy-efficient upgrades cost him $2,500 per
house, and he more than doubles that in profit margin.
Innovations
Ideal has had its share of firsts. It was the first ENERGY STAR builder in Oklahoma.
According to McKown, Ideal was also the first builder in the United States to build
ENERGY STAR homes for under $150,000. Ideal was also one of the first in the
Oklahoma market to install premium low-emissivity vinyl windows, instead of
aluminum frame windows.
McKown’s research in value-added construction to improve Ideal’s competitiveness
led to Building America and its partner, the Energy and Environmental Building
Association (EEBA), for which McKown served as president in 2002.
MARKETERS
Energy efficiency
delivers the value that
customers demand
SITE PLANNERS
& DEVELOPERS
Properly situated houses
pay big dividends
DESIGNERS
Well-crafted designs
capture benefits for builders,
buyers, and business
SITE SUPERVISORS
Tools to help with
project management
TRADES
Professional tips for fast
and easy installation
CASE STUDIES
Bringing it all together
Ideal also partnered with the American Lung Association’s Health House Program
and built one if its original test houses on a slim $112,000 price tag.
In two of its home lines, Ideal also offers buyers a utility bill guarantee program called
Engineered for Life developed by Louisiana Pacific. If a home owner’s heating and
cooling bills go over a pre-determined guaranteed usage in any one year, the owner is
reimbursed 100% of the cost difference.
Building America Best Practices Series: Volume 4 – Builders and Buyers Handbook for
Improving New Home Efficiency, Comfort, and Durability in the Mixed-Humid Climate
Version 1, 9/2005 • CASE A-1
Case Study: Ideal Homes
McKown sees one of his company’s major innovations as selling the value of energy
efficiency. Ideal is so committed to selling the energy efficiency of its homes, it puts
new sales staff through three weeks of intensive training in energy efficiency.
BUILDER PROFILE
McKown credits Building America with teaching Ideal how to think of the house as a
whole system. In addition to promoting higher efficiency windows, Building America also
gave Ideal training in moisture management and drainage issues, and fresh air ventilation.
Where:
Norman, Oklahoma
“Before we started working with Building America, we said, ‘We don’t have moisture
issues because we build brick houses. That’s not true. We started working with
Building America’s Building Science Corporation and we learned we had brick leaks.”
“The level of training and knowledge that Building America has exposed us to is
invaluable,” explains McKown. “The houses we put out today are just a lot better
product…because of moisture management. I think the number one issue facing home
owners is moisture management. Construction detailing around windows and doors is
something that the building industry doesn’t truly understand. You know, no where in
the building code do they inspect for flashing.”
Comfort, Durability, and Health
All Ideal Homes exceed the standard practices that
make homes energy efficient and healthy by adopting
Building America practices like mastic sealed ducts,
extra care in sealing house wrap, and caulking around
windows and wall penetrations, whole house fans,
and fresh air intakes.
Ideal Homes guarantees the
utility bills of their Signature
Line through Louisiana Pacific’s
Engineered for Life Program.
The guarantee is that the heating
and cooling costs in a home
will not exceed pre-determined
guaranteed usage in any one-year
period or the homeowner will be
reimbursed for 100% of the cost
of the difference.
McKown believes the fresh air ventilation system
with the fan recycler is the product his customers
appreciate the most. “Everyone in Oklahoma has allergies and asthma. We ask that standard
question in our surveys, and we always get a positive response. I love to see comments on our
surveys like ‘we really believe we have less allergies and asthma in this house.’”
The Bottom Line
According to McKown, Ideal is able to meet Building America standards and still
earn 32% profit margins because they look at the whole house as a system and choose
which improvements make the most sense. For example they chose not to put ducts in
conditioned space, but they meet 5% duct leakage requirements by attention to sealing.
A tighter envelope allows them to save money by downsizing the HVAC equipment.
McKown also credits a strong relationship with subs. He tells of an HVAC contractor
who came up with the idea of applying mastic to some duct connections in the shop
instead of onsite, cutting onsite installation time in half. McKown said subs have also
developed better techniques for installing insulation and window flashing once they
understood the value of these Building America recommendations.
“Working with Building America has changed a lot of our systems and processes. If
you [other builders] will do it and train your sales people in how to sell it, you’ll make
the most money you will ever make as a builder because you can get out of the price
competitive game and increase your net profit,” says McKown.
Building America Best Practices Series: Volume 4 – Builders and Buyers Handbook for
Improving New Home Efficiency, Comfort, and Durability in the Mixed-Humid Climate
Ideal Homes
Founded:
1989
Employees:
Approximately 85
Development:
Seminole Point
Size:
Approximately 600 homes to
date all in the Signature Line
Square footage:
1,277 to 2,325 sq.ft.
Price range:
$120,000 to $185,000
Key Features:
• 90% efficient central gas
heating
• SEER 14 high-efficiency
central HVAC systems
• Blown-in R-19 insulation
for the for the walls and R
30 insulation for the ceiling
• Vinyl thermopane windows
with low-e glass
• Fresh-air ventilation system
with a fan recycler
“ I think the number one issue
facing home builders is moisture
management. Construction
detailing around windows and
doors is something that the
building industry doesn’t truly
understand. You know, no
where in the building code do
they inspect for flashing.”
Vernon McKown,
Vice President of Ideal Homes
Version 1, 9/2005 • CASE A-2
Melrose Commons II
New York
INTRODUCTION
Taking action in
your community
Big Energy Savings for the Little Guy
Making energy-efficient housing available for folks who could really benefit from the
savings is something New York City builder Les Bluestone loves to do. “If you can
save $1,000 a year on heating bills – to someone who is making a $1million a year,
this doesn’t mean much. But to someone who is making $30,000 to $40,000, this is
a big piece of change.”
Bluestone’s company, Blue Sea
Development Company, specializes in
affordable and low-income housing. They
first worked with Building America in
2002 on a 90-unit, multi-family urban
infill in the South Bronx called Melrose
Commons II under New York City’s
“New Homes Program,” which is jointly
administered by the NYC Housing
Partnership and the NYC Department of
Housing Preservation and Development.
The development won first place in the
Northeast Sustainable Energy Association’s
2003 Green Building Awards’ residential
category, competing against high-end,
single-family custom homes.
In January 2004, the Melrose
Commons II project in Bronx,
New York, was awarded the U.S.
Department of Housing and
Urban Development (HUD)
Secretary’s Platinum Award for
Excellence category in the 20th
Annual Best in American Living
Award competition.
Melrose also won the 2003
Northeast Green Building
Award in the residence category,
sponsored by the Northeast
Sustainable Energy Association
(NESEA)
Shopping for value,
comfort, and quality
MANAGERS
Putting building
science to work for
your bottom line
MARKETERS
Energy efficiency
delivers the value that
customers demand
The entire inside framing of the buildings
in this Building America project in New
York is wrapped with _-inch expanded
polystyrene (EPS) board creating a thermal
break between the interior walls and the
exterior walls which were precast concrete.
“This made a big, big difference,” said
builder Les Bluestone
Since completing Melrose II in 2003, Bluestone has built more than 250 units
following Building America approaches in two additional developments in and
around New York.
Award Winning
HOMEOWNERS
“This [energy-efficient affordable housing]
was something we always wanted to do. This
is important. These are people who really need
it the most and have the least access to it. It is
something we really believe in,” said Bluestone
about his company’s decision to work with
Building America.
Bluestone notes that Blue Sea made a
substantial contribution toward the additional
costs on their first project, in part because they
had already bid the job at a set price prior to
working with Building America. Bluestone feels
that market rate builders should have no trouble
recouping their costs. But Bluestone is not in it
just for the money. “As long as we can build a
good product and be able to continue on to the
next job, everyone wins.”
Building America Best Practices Series: Volume 4 – Builders and Buyers Handbook for
Improving New Home Efficiency, Comfort, and Durability in the Mixed-Humid Climate
SITE PLANNERS
& DEVELOPERS
Properly situated houses
pay big dividends
DESIGNERS
Well-crafted designs
capture benefits for builders,
buyers, and business
SITE SUPERVISORS
Tools to help with
project management
TRADES
Professional tips for fast
and easy installation
CASE STUDIES
Bringing it all together
Version 1, 9/2005 • CASE B-1
Case Study: Melrose Commons
Buyers lucky enough to get one of Bluestone’s Building America units certainly win.
BUILDER PROFILE
Building America’s Consortium for Advanced Residential Buildings (CARB) found
that the Melrose homes consumed 80% less energy per square foot to heat than the
average affordable housing in New York City, and almost 90% less than the average
new or gut-rehabilitated housing.
Blue Sea Construction
Company, LLC
A big plus for Bluestone is fewer callbacks. “Our heating callbacks have dropped
tremendously in the last year. I think we had two heating calls all winter,” Bluestone notes.
Founded: 2001
Employees: 25
Development: Melrose
Commons II, Bronx, New York
Innovations
Bluestone is excited about several energy-efficient innovations they incorporated in the
three-story townhouse units. The townhouses are built using an exterior and interior
structural panelized system (manufactured by Oldcastle Precast) that is made of solid
concrete and brick, designed, engineered,
and manufactured in plants and
shipped to the site. “These are structural
precast panels, which are different from
most other precast panels,” explained
Bluestone. “Typically in a precast panel
building, a structure is erected, and then
the erectors come back and set the panels
as the skin of the building. In these, the
skin is actually holding up the building.”
Some of the benefits of these panels
include a faster construction speed, lower
labor costs, less onsite waste, and fewer
seams for a tighter building structure.
Precast panels helped to reduce labor costs
and air leakage.
Through modeling performed by CARB, Bluestone and his partner learned that in
wall construction commonly believed to be R-15 or R-20, the walls really had about
half those ratings because of thermal bridging. “The heat was being transferred through
the studs to the outside walls, and that caused a considerable amount of heat loss,”
said Bluestone. “So, for our buildings, before we did any of the interior framing,
we put up a layer of rigid insulation, like an
interior envelope.” They used a ½-inch expanded
polystyrene (EPS) board between the exterior walls
and the interior walls. “We wrapped the entire
inside of the building with this rigid insulation,
creating a real thermal break for minimal
transference. This made a big, big difference.”
Wall construction consisted of 6 inch
and 8 inch concrete panels, backed
with half-inch expanded polystyrene
foam insulation, steel framing, and
R-11, faced, fiberglass wall cavity
insulation.
Where: New York
The basement has an insulated perimeter with R-2
in EPS two feet below grade and 2 inches of rigid
fiberglass at all exposed foundation wall surfaces.
The roof’s concrete plank is insulated with R-21
3.1-inch polyisocyanurate foam board.
Other innovative approaches Bluestone cites
include an indirect hot water heating system.
“The water is heated on demand from a coil
Building America Best Practices Series: Volume 4 – Builders and Buyers Handbook for
Improving New Home Efficiency, Comfort, and Durability in the Mixed-Humid Climate
Size: 30 three-family homes
Square footage: 4,400 sq.ft.
for three dwelling units
Price range: Designed and
financed for families making less
than $42,000 per year. $289,000
for three units, with the owners
using rental income from the
two other units to meet their
mortgage payments.
Key Features:
• Solid concrete and brick
structural precast panels manufac
tured by Oldcastle Precast
• High fly-ash concrete
• Rigid ½-inch expanded polystyrene
EPS insulation board between
metal studs and exterior wall
• Double-glazed low-e coated-glass,
vinyl ENERGY STAR windows
• Additional roof insulation and
aluminized roof coatings to reflect
summer sun
• Sealing and caulking at interior
and exterior sides of all walls and
exterior penetrations
• Sealing of all exhaust ductwork
• 87.4% efficient sealed combustion
direct vent boilers
• High-efficiency 65-gallon indirect
water heater
• Digital programmable thermostat
in each unit
• Computer boiler controllers with
outdoor temperature sensors
• ENERGY STAR appliances
• ENERGY STAR compact
fluorescent lighting fixtures
• 100% recycled content PET
carpeting made from plastic
bottles and containers laid over
recycled rubber padding
Version 1, 9/2005 • CASE B-2
Case Study: Melrose Commons
and stored in a tank. You gain the benefit of a super insulated storage tank and the
high-efficiency burner,” Bluestone explained. He also notes that each floor was zoned
separately, extra insulation above code was used, and ENERGY STAR windows were
installed.
Bluestone sees a growing trend in the availability of energy efficient and sustainable
products. “When we started out the choices of technology and equipment that were
available you could count on one hand if you had a few missing fingers, but now more
manufacturers are offering choices.”
Bluestone used recycled materials and environmentally friendly materials throughout
the homes including recycled-content kitchen vinyl composition tile flooring and
100% recycled content PET carpeting made from recycled plastic bottles and
containers laid over recycled rubber padding.
Melrose II’s innovations don’t stop at energy efficiency. The development is based on a
unique design concept that could help homebuyers gain financial self-sufficiency. Each
4,400-square-foot townhouse contains three units. The owner resides on the first floor,
half of the second floor, and has a full cellar as well. The other half of the second floor
contains a one-bedroom apartment, and the third floor is a full-floor two-bedroom
apartment, both of which can be rented.
“It is just as easy to do
things right as it is to do
things wrong. Once the
subcontractors understand
what our definition of right is,
building to Building America
standards is not a problem.”
Les Bluestone, owner of Blue Sea
Development Company, energy
efficient affordable home builders
in New York City.
Each three-family townhouse was sold for approximately $289,000. But with the rental
income, the homes are affordable for those making less than $42,000 per year.
Comfort, Durability, and Health
“Sustainable construction and healthy indoor air quality is key to us,” states Bluestone.
To ensure such quality, each unit received a high-efficiency, direct-vent, gas boiler with
an indirect-storage water heater. These sealed-combustion boilers eliminated the risk of
combustion backdrafting and potential carbon monoxide poisoning. Each bath and kitchen
contains separately switched mechanical fans that are programmed to provide continuous
background ventilation. Also, each unit received a programmable digital thermostat.
Additional Building America details like extra sealing and caulking of interior and exterior wall
penetrations and duct sealing help keep out drafts, bugs, and air pollution. Aluminized roof
coatings reflect sun, keeping the interior cooler during the summer months.
The Melrose II townhouses rate at 4.5 Btu/ft2/heating degree day for heating energy. The
development got a HERS score ranging from 89 – 91. According to CARB, the domestic
hot water energy usage at Melrose II is almost 70% less energy per square foot than the
average affordable housing in the city, and more than 80% less than the average new or
gut-rehabilitated housing.
Each home is equipped with a
high-efficiency (87% AFUE)
sealed-combustion boiler that
provides both heat and hot water,
and avoided the construction and
costs of a chimney.
The Bottom Line
With each Building America development they do, Bluestone says his crews get more
and more efficient. “It is just as easy to do things right as it is to do things wrong.
Once the subcontractors understand what our definition of right is, building using
Building America principles is not a problem.”
Bluestone’s advice to other builders: “The first one is going to hurt, but you should do
it. In the end, you will never look back.”
Building America Best Practices Series: Volume 4 – Builders and Buyers Handbook for
Improving New Home Efficiency, Comfort, and Durability in the Mixed-Humid Climate
Version 1, 9/2005 • CASE B-3
John Wieland
The New American Home 2002
Atlanta, Georgia
INTRODUCTION
Taking action in
your community
Showcase Shows Off Efficiency
A showcase Georgia plantation home proves that you can have the grandeur of Tara
and energy efficiency too. John Wieland Homes of Atlanta, Georgia, teamed with
Building America’s IBACOS Consortium to build the sprawling, 6,431-sq. ft., $1.3
million home, which despite its grandeur uses over
50% less energy to heat and cool
than similar sized homes and
achieved a Home Energy Rating
System (HERS) score of 91.1.
The home, described by
Horstemeyer as a combination
of traditional Georgia colonial
and Caribbean plantation style,
encompasses 80,600 cubic feet on
two floors plus a finished basement.
The house has four bedrooms,
five-and a half bathrooms, a
rotunda and entrance hall, a
waterfall, an exercise/massage room,
a sauna, a gallery, a children’s loft,
and a veranda.
Innovations
Shopping for value,
comfort, and quality
MANAGERS
Putting building
science to work for
your bottom line
MARKETERS
“We wanted to prove that you
could do it [energy efficiency]
with a house of this magnitude,”
explains Michelle Horstemeyer,
the lead builder from John
Wieland Homes. “It was a thrill
to see just how much energy
efficiency was possible.”
The home was co-sponsored by
the National Association of Home
Builders (NAHB) and Builder
Magazine as “the New America
Home” of 2002 for the 2002
International Builders Show held
in Atlanta.
HOMEOWNERS
Energy efficiency
delivers the value that
customers demand
SITE PLANNERS
& DEVELOPERS
Properly situated houses
pay big dividends
Building America recommended energy saving
features like low-emissivity windows, an energy
recovery ventilator that delivers fresh air to the return
plenum, high-efficiency HVAC equipment, radiant
roof sheathing, draftstopping for building airtightness,
and a housewrap weather barrier.
DESIGNERS
Well-crafted designs
capture benefits for builders,
buyers, and business
SITE SUPERVISORS
Tools to help with
project management
TRADES
Professional tips for fast
and easy installation
CASE STUDIES
Bringing it all together
John Wieland Homes’ New American Home of
2002 in Atlanta Georgia got help from Building
America to achieve a HERS score of 91.1 and reduce
energy use by 50% over similar sized homes.
“I had not built using Building America principles before building this home,”
explains Horstemeyer. “I learned that it is not nearly as hard as I thought it would
be. We had heard that building to all these new energy efficiency guidelines would be
real time consuming and expensive, and it doesn’t have to be either. IBACOS helped
Building America Best Practices Series: Volume 4 – Builders and Buyers Handbook for
Improving New Home Efficiency, Comfort, and Durability in the Mixed-Humid Climate
Version 1, 9/2005 • CASE C-1
Case Study: John Wieland Homes & Neighborhoods, inc.
us in what to do and how to implement Building America principles. Also, Lennox was
partnered with us, so we had top-of-the-line equipment, and this helped a lot.”
Energy-saving features include:
BUILDER PROFILE
John Wieland Homes
and Neighborhoods, Inc.
• Air distribution was optimized through a carefully detailed and engineered
duct layout that divided the home into five thermal zones, each with
temperature controls.
Where:
Atlanta, Georgia
• Ductwork was kept within conditioned space wherever possible.
Founded:
1970
• Two energy-efficient Lennox furnaces (93% annual fuel utilization
efficiency) and two air conditioners were used (11.7 and 12.5 seasonal
energy efficiency ratio).
Employees:
1,000
• An energy recovery ventilator operates on
a continuous basis to provide mechanical
ventilation. The unit delivers fresh air,
tempered by the ventilator, into the
return-air side of each furnace. It has the
ability to provide dehumidification of the
ventilation air in the summer and heat
recovery in the winter while ensuring
better indoor air quality. Ultraviolet
air treatment systems were included in
each system as well. Each system consists
of a single lamp and is considered to have
moderate-efficiency performance against
airborne bacteria.
Development:
The New American Home
2002 in Vinings Estates
Size:
30 three-family homes
Square footage:
6,431 (heated) square feet
The Energy Recovery Ventilator
tempers outdoor air before delivering
it to heating and cooling equipment.
• To improve building airtightness, holes were draftstopped to ensure air
barrier continuity. Locations for draftstopping include behind bathtubs,
fireplaces, chases on exterior walls, at chases through the ceiling, and at walls
separating conditioned and unconditioned space. The crawlspace area is
unvented and conditioned.
• The vaulted ceiling cavities were filled with two layers of R-13 fiberglass batt
insulation (for a R-26 total). Flat sections were insulated with R-30 fiberglass
batt insulation. Exterior walls were insulated with R-15 high-density fiberglass
batt insulation. The foundation was insulated with Superior Wall System®,
which features R-5 foam board insulation covering the entire exterior face, and
the 6-inch wall cavities were filled with R-19 batt insulation.
Horstemeyer notes that by working with Building America she learned a simple and
innovative recycling approach that she applies to all her job sites. “We grind up the
cardboard boxes, the shingles and all the left-over wood, and then use this as mulch on
the job site.” On prior projects all of their construction debris went to the landfill.
Comfort, Durability, and Health
“Our goal is the comfort of our homeowners,” states Horstemeyer. “Early on the
owners commented that they were surprised that their energy bills were not what they
expected for a house this size.”
Building America Best Practices Series: Volume 4 – Builders and Buyers Handbook for
Improving New Home Efficiency, Comfort, and Durability in the Mixed-Humid Climate
Price range:
Sold for $1.25M.
Cost to build $1.3M
Key Features:
• Low-e windows
(U=0.33, SHGC=0.32)
• Unvented crawl space
and precast foundation
• Energy recovery ventilator
delivers fresh air to return
plenum in each air handler
• High-efficiency HVAC
equipment
• Radiant roof sheathing
• Draftstopping for building
airtightness
• Housewrap weather barrier
• Ductwork leakage target
160 cfm
• Lennox condensing units
efficiency to 12 SEER,
9 tons total
• Direct-vent gas furnaces,
93% AFUE
Version 1, 9/2005 • CASE C-2
Case Study: John Wieland Homes & Neighborhoods, inc.
Horstemeyer notes the importance of educating both
the buyers and the trades people about the benefits of
building the Building America way. “A lot of people
do not really understand the real benefits of it,” she
explains. “A lot of the benefit is air quality. People
here in the South suffer from allergies. If you are not
introducing that unfiltered air into your home, then
you are not bringing in those pollutants and allergens
and pollen.”
Properly designed ducts reduce
costs and increase comfort.
Finally, special attention was paid to moisture
control. Flexible flashing membrane was placed on
the window sill rough opening, flanges were backcaulked, and then as the window was installed, the
top flange was slipped underneath the housewrap.
The areas of the house with synthetic stone cladding
required building felt (#15) as a back-up layer because
the stone can act as a holding tank for water. The felt
creates a drainage plain or surface that allows water
to run off, keeping the interior part of the wall from
getting wet.
The Bottom Line
Asked if she applies Building America principles to the houses she builds today,
Horstemeyer replies, “We have chosen to continue with the things that are cost
effective and have perceived value to our homeowners. A lot of the techniques have
become required because of the new energy code, such as low-e windows and
fire-rated caulking.”
Horstemeyer also notes that she used many Building America features when she
recently built her own home. “We did the roof shielding, low-e windows, tankless
(on-demand) water heater, and sealed penetrations. I also used Techshield, a radiant
barrier shielding for the roof, which helps deflect the heat of the sun and is keeping
my heating bills lower in the summer.”
Advanced framing helps to
save building materials and
construction costs and create more
room for insulation, making the
house more energy efficient.
Building America Best Practices Series: Volume 4 – Builders and Buyers Handbook for
Improving New Home Efficiency, Comfort, and Durability in the Mixed-Humid Climate
Version 1, 9/2005 • CASE C-3
Appendix I
Homebuyer’s Checklist
Below is a more detailed list of building features for those who really want to investigate their house.
To really see how some of these measures are installed, visit houses that are under construction.
MEASURE
Building
America
Builder
#1
Builder
#2
Builder
#3
HEATING AND COOLING EQUIPMENT
ENERGY STAR qualified air conditioning of SEER* 13 or greater
(SEER 14 starting Jan 2006)
Yes
ENERGY STAR qualified heat pump
Yes
ENERGY STAR qualified boiler
Yes
ENERGY STAR qualified furnace of AFUE* 90
Yes
ENERGY STAR qualified programmable thermostat
Yes
Ductwork sealed with mastic (no duct tape)
Yes
5% or less duct leakage found with pressure test
Yes
Duct Insulation:
R-4 in conditioned space, R-8 in attic, R-6 in crawlspace
Yes
House plans show duct layouts
Yes
Ducts located in conditioned space as much as possible
Yes
Ducts sized according to industry standards in Manual D
Yes
Heating and cooling equipment sized according to industry
standards in Manual J
Yes
House pressure balanced with jump ducts
Yes
HVAC* equipment and duct work was inspected
and tested after installation
Yes
INSULATION (take a look at a house under construction before sheetrock is installed)
Insulation installed behind tubs, landings, and other hard to
reach places
Yes
Insulation fills entire cavities – no voids or compressed batts –
Attic insulation level without gaps and covers entire attic floor
Yes
Where fiberglass batt insulation is used it is high-density
Yes
Rim joists are insulated
Yes
WINDOWS (take a look at a house under construction before exterior siding is installed)
ENERGY STAR qualified windows, doors, and skylights
Yes
Windows flashed to help repel water
Yes
Windows rated to 0.35 U-factor and SHGC
Yes
Building America Best Practices Series: Volume 4 – Builders and Buyers Handbook for
Improving New Home Efficiency, Comfort, and Durability in the Mixed-Humid Climate
Version 1, 9/2005 • APPENDIX I-1
Appendix I: Homebuyer’s Checklist
MOISTURE MANAGEMENT (take a look at a house under construction before exterior siding is installed)
Ground slopes away from house
Yes
Housewrap or building paper covers exterior sheathing in
wood framed houses
Yes
Roof flashing in valleys, where walls and roofs intersect, and
at other places where water may enter the house – the more
complex the roof, the more flashing you should see
Yes
Overhangs for shade and to direct water away from walls
Yes
AIR BARRIERS
All penetrations through exterior walls sealed
Yes
Careful sealing of sheetrock or exterior sheathing
Yes
Canned lights rated as airtight and for insulated ceiling (ICAT)
Yes
Electrical boxes on exterior walls caulked or gasketed
Yes
Holes into attic sealed
Yes
Attic hatch weather-stripped and insulated
Yes
Air leakage determined with house depressurization test
Yes
Wall-roof intersection carefully sealed to avoid ice dams
Yes
Draft stops installed behind tubs, showers, stairs, and fireplaces
Yes
FOUNDATION MEASURES
Radon control measures installed
Yes
4 to 6 inch gravel base under slab and basement floors
Yes
Polyethylene (plastic) vapor barrier between gravel and slab
Yes
Conditioned crawlspace
Yes
Exterior wall insulation
Yes
PLUMBING
No pipes in exterior walls
Yes
Pipe insulation
Yes
YOUR FEATURES FOR COMPARISON
*SEER: Seasonal Energy Efficiency Ratio
*AFUE: Annual Fuel Utilization Efficiency
*HVAC: heating, ventilation, and air conditioning
If you want to know more about any of these or other house features review the other chapters of the Best
Practices guide. Other chapters are designed to help site planners, designers, site supervisors, and crafts
people design and build efficient, comfortable, and durable homes.
Building America Best Practices Series: Volume 4 – Builders and Buyers Handbook for
Improving New Home Efficiency, Comfort, and Durability in the Mixed-Humid Climate
Version 1, 9/2005 • APPENDIX I-2
Appendix II
Energy & Housing Glossary
Accreditation
The process of certifying a Home Energy Rating System
(HERS) as being compliant with the national industry
standard operating procedures for Home Energy
Rating System.
AFUE Annual Fuel Utilization Efficiency (AFUE)
Measures the amount of fuel converted to space heat in
proportion to the amount of fuel entering the furnace.
This is commonly expressed as a percentage. A furnace
with an AFUE of 90 could be said to be 90% efficient.
AFUE includes any input energy required by the pilot
light but does not include any electrical energy for
fans or pumps.
Air Flow Retarder
Sealants used to keep outside air and inside air out
of the building envelope. Four common approaches
to retarding air flow include careful sealing using the
following building components: drywall and framing,
plastic sheets (should not to be used in hot and humid
climates) between drywall and framing, exterior
sheathing, and building paper. Air flow retarders define
the pressure boundary in a house that separates indoor
and outdoor air.
Building Envelope
The outer shell, or the elements of a building, such
as walls, floors, and ceilings, that enclose conditioned
space. See also Pressure Boundary and Thermal
Boundary.
Btu (British Thermal Unit)
A standard unit for measuring energy. One Btu is the
amount of energy required to raise the temperature of
one pound of water by one degree Fahrenheit from
59 to 60. An Inches-Pounds unit.
CABO (Council of American Building Officials)
A national organization of building code officials and
interested parties, which, through a national consensus
process, developed, adopted and promulgated the
national Model Energy Code (MEC). CABO has
recently become CABO International and has taken on
the administrative responsibility for the development
of a uniform international building code through an
International Code Council (ICC).
Capacity
The rate at which a piece of equipment works. Cooling
capacity is the amount of heat a cooling system can
remove from the air. For air conditioners total capacity
is the sum of latent capacity, the ability to remove
moisture from the air, and the sensible capacity, the
ability to reduce dry-bulb temperature. Heating system
capacity indicates how much heat a system can provide.
Heating and cooling capacities are rated in Btu per hour.
Chase
An enclosure designed to hold ducts, plumbing,
electric, telephone, cable, or other linear components.
A chase designed for ducts should be in conditioned
space and include air flow retarders and thermal barriers
between it and unconditioned spaces such as attics.
Closed Combustion
See Sealed Combustion, Direct Vent, and Power Vent.
Construction Documents
The drawings (plans) and written specifications that
describe construction requirements for a building.
COP (Coefficient of Performance)
A measure of efficiency typically applied to heat pumps.
The COP for heat pumps is the ratio, at a given
point in time, of net heat output to total energy input
expressed in consistent units and under designated
conditions. Heat pumps result in a COP greater than
1 because the system delivers or removes more heat
energy than it consumes. Other specific definitions of
COP exist for refrigeration equipment. See HSPF for a
description of a unit for seasonal efficiency.
Building America Best Practices Series: Volume 4 – Builders and Buyers Handbook for
Improving New Home Efficiency, Comfort, and Durability in the Mixed-Humid Climate
Version 1, 9/2005 • APPENDIX II-1
Appendix II: Energy & Housing Glossary
Debt-to-Income Ratio
The ratio, expressed as a percentage, which results
when a borrower’s total monthly payment obligations
on long-term debt are divided by their gross monthly
income. This is one of two ratios (housing expenseto-income ratio being the other) used by the mortgage
industry to determine if a prospective borrower qualifies
(meets the underwriting guidelines) for a specific
home mortgage. Fannie Mae, Freddie Mac and FHA
underwriting guidelines set an upper limit of 36% on
this value for conventional loans but increase (“stretch”)
the ratio by 2% for qualifying energy efficient houses.
Direct Vent
A sealed ventilation system for combustion appliances
that draws combustion air from outside the structure
and vents combustion exhaust outside the structure.
These systems may be combined with power vent
exhausts. See Power Vent and Sealed Combustion.
Dry-Bulb Temperature
The temperature of air indicated on an ordinary
thermometer, it does not account for the affects
of humidity.
ECM (Energy Conservation Measure)
An individual building component or product that
directly impacts energy use in a building.
EEM (Energy Efficient Mortgage)
Specifically, a home mortgage for which the borrower’s
qualifying debt-to-income and housing expense-to
income ratios have been increased (“stretched”) by
2% because the home meets or exceeds CABO’s 1992
version of the Model Energy Code (MEC). This socalled “stretch” mortgage is nationally underwritten
by Fannie Mae, Freddie Mac and the Federal Housing
Administration (FHA). This term is often used
generically to refer to any home mortgage for which the
underwriting guidelines have been relaxed specifically
for energy efficiency features, or for which any form of
financing incentive is given for energy efficiency.
EER (Energy Efficiency Ratio)
A measurement of the instantaneous energy efficiency
of cooling equipment, normally used only for electric
air conditioning. EER is the ratio of net cooling
capacity in Btu per hour to the total rate of electric
input in watts, under designated conditions. The
resulting EER value has units of Btu per watt-hour.
EF (Energy Factor)
A standardized measurement of the annual energy
efficiency of water heating systems. It is the annual hot
water energy delivered to a standard hot water load
divided by the total annual purchased hot water energy
input in consistent units. The resultant EF value is a
percentage. EF is determined by a standardized U.S.
Department of Energy (DOE) procedure.
Energy (use)
The quantity of onsite electricity, gas or other fuel
required by the building equipment to satisfy the
building heating, cooling, hot water, or other loads or
any other service requirements (lighting, refrigeration,
cooking, etc.)
Energy Audit
A site inventory and descriptive record of features
impacting the energy use in a building. This includes,
but is not limited to: all building component descriptions
(locations, areas, orientations, construction attributes
and energy transfer characteristics); all energy using
equipment and appliance descriptions (use, make, model,
capacity, efficiency and fuel type) and all energy features.
ENERGY STAR® Home
A home, certified by the U.S. Environmental Protection
Agency (EPA), that is at least 30% more energy
efficient than the minimum national standard for home
energy efficiency as specified by the 1992 MEC, or as
defined for specific states or regions. ENERGY STAR
is a registered trademark of the EPA.
Envelope
See Building Envelope
Fannie Mae
(FNMA - Federal National Mortgage Association)
A private, tax-paying corporation chartered by the U.S.
Congress to provide financial products and services that
increase the availability of housing for low-, moderate-,
and middle-income Americans.
FHA (Federal Housing Administration)
A division of the U.S. Department of Housing and
Urban Development (HUD). FHA’s main activity is
the insurance of residential mortgage loans made by
private lenders.
Building America Best Practices Series: Volume 4 – Builders and Buyers Handbook for
Improving New Home Efficiency, Comfort, and Durability in the Mixed-Humid Climate
Version 1, 9/2005 • APPENDIX II-2
Appendix II: Energy & Housing Glossary
Freddie Mac
(FHLMC - Federal Home Loan Mortgage Corporation)
A stockholder-owned organization, chartered by the
U.S. Congress to increase the supply of mortgage funds.
Freddie Mac purchases conventional mortgages from
insured depository institutions and HUD-approved
mortgage bankers.
Grade Beam
A foundation wall that is poured at or just below the grade
of the earth, most often associated with the deepened
perimeter concrete section in slab-on-grade foundations.
HERS (Home Energy Rating System)
A standardized system for rating the energy-efficiency
of residential buildings.
HERS Energy-Efficient Reference Home (EERH)
The EERH is a geometric “twin” to a home being
evaluated for a HERS rating and according to a newlyrevised system, is configured to be minimally compliant
with the 2004 International Energy Conservation Code.
HERS Provider
An individual or organization responsible for the
operation and management of a Home Energy
Rating System (HERS).
HERS Rater
An individual certified to perform residential building
energy efficiency ratings in the class for which the rater
is certified.
HERS Score
A value between 0 and 100 indicating the relative
energy efficiency of a given home as compared with the
HERS Energy-Efficient Reference Home as specified by
the HERS Council Guidelines. The greater the score,
the more efficient the home. A home with zero energy
use for the rated energy uses (heating, cooling and hot
water only) scores 100 and the HERS Reference Home
scores 80. Every one point increase in the HERS score
amounts to a 5% increase in energy efficiency.
Housing Expense-to-Income Ratio
The ratio, expressed as a percentage, which results when
a borrower’s total monthly housing expenses (P.I.T.I.)
are divided by their gross monthly income. This is
one of two ratios (debt-to-income ratio being the
other) used by the mortgage industry to determine if a
prospective borrower qualifies (meets the underwriting
guidelines) for a specific home mortgage. Fannie Mae,
Freddie Mac and FHA underwriting guidelines set an
upper limit of 28% on this value for conventional loans
but increase (“stretch”) the ratio by 2% for qualifying
Energy Efficient Mortgages (EEM).
Housewrap
Any of several spun-fiber polyolefin rolled sheet goods
for wrapping the exterior of the building envelope.
HSPF (Heating Season Performance Factor)
A measurement of the seasonal efficiency of an electric
heat pump using a standard heating load and outdoor
climate profile over a standard heating season. It
represents the total seasonal heating output in Btu
divided by the total seasonal electric power input in
watt-hours (Wh). Thus, the resultant value for HSPF
has units of Btu/Wh.
Jump Duct
A flexible, short, U-shaped duct (typically 10-inch
diameter) that connects a room to a common space as
a pressure balancing mechanism. Jump ducts serve the
same function as transfer grilles.
Load
The quantity of heat that must be added to or removed
from the building (or the hot water tank) to satisfy
specific levels of service, such as maintaining space
temperature or hot water temperature at a specified
thermostat setting (see also the definitions of energy
and thermostat).
Low-E
Refers to a coating for high-performance windows, the
“E” stands for emissivity or re-radiated heat flow. The
thin metallic oxide coating increases the U-value of
the window by reducing heat flow from a warm(er) air
space to a cold(er) glazing surface. Low-E coatings allow
short-wavelength solar radiation through windows, but
reflect back longer wavelengths of heat.
MEC (Model Energy Code)
A “model” national standard for residential energy
efficiency. The MEC was developed through a
national consensus process by the Council of American
Building America Best Practices Series: Volume 4 – Builders and Buyers Handbook for
Improving New Home Efficiency, Comfort, and Durability in the Mixed-Humid Climate
Version 1, 9/2005 • APPENDIX II-3
Appendix II: Energy & Housing Glossary
Building Officials (CABO) and is the accepted
national minimum efficiency standard for residential
construction. Since MEC is a model code, it does not
have the “force of law” until it is adopted by a local code
authority. The MEC is used as the national standard
for determining Energy Efficient Mortgage (EEM)
qualification, and it serves as the national “reference
point” used by Home Energy Rating Systems (HERS)
in the determination of energy ratings for homes.
Mechanical Ventilation
The active process of supplying or removing air to or
from an indoor space by powered equipment such as
motor-driven fans and blowers, but not by devices such
as wind-driven turbine ventilators and mechanically
operated windows.
Performance Test
An on-site measurement of the energy performance
of a building energy feature or an energy using device
conducted in accordance with pre-defined testing and
measurement protocols and analysis and computation
methods. Such protocols and methods may be defined
by national consensus standards like those of the
American Society of Heating, Refrigerating and Air
Conditioning Engineers (ASHRAE) and the American
Society for Test and Measurement (ASTM).
Perm
A unit of measure of water vapor permeance. One
perm equals one grain of water vapor per hour flowing
through one square foot of material at a differential
vapor pressure equal to one inch of mercury. The
greater the number, the more water vapor that will pass
through a given material.
P.I.T.I.
An abbreviation which stands for principal, interest,
taxes, and insurance. These generally represent a
borrower’s total monthly payment obligations on a
home loan. The taxes and insurance portion are often
paid monthly to an impound or escrow account and
may be adjusted annually to reflect changes in the
cost of each.
Power Vent
A sealed exhaust ventilation system for combustion
appliances that uses a fan to move combustion exhaust out
of the structure. See Direct Vent and Sealed Combustion.
Pressure Boundary
The point in a building at which inside air and outside
air are separated. If a building were a balloon, the
rubber skin would form the pressure boundary. Where
inside and outside air freely mingle there is no
pressure boundary.
Pressurization Test
A procedure in which a fan is used to place a house,
duct system, or other container, under positive or
negative air pressure in order to calculate air leakage.
RESNET (Residential Energy Services Network)
The national association of energy rating providers.
Rated Home
A specific residence that is evaluated by an energy rating.
R-Value
Measures a material’s ability to slow down or resist the
transfer of heat energy, also called thermal resistance.
The greater the R-value, the better the resistance, the
better the insulation. R-values are the reciprocal of
U-values. See U-values for more information.
Sealed Combustion
Sealed combustion means that a combustion appliance,
such as a furnace, water heater, or fireplace, acquires all
air for combustion though a dedicated sealed passage
from the outside; combustion occurs in a sealed
combustion chamber, and all combustion products
are vented to the outside through a separate dedicated
sealed vent. See Direct Vent and Sealed Combustion.
SEER (Seasonal Energy Efficiency Ratio)
A measurement similar to HSPF except that it measures
the seasonal cooling efficiency of an electric air
conditioner or heat pump using a standard cooling load
and outdoor climate profile over a standard cooling
season. It represents the total seasonal cooling output in
Btu divided by the total seasonal electric input in watthours (Wh). The SEER value are units of Btu/Wh.
Semi-Permeable
The term vapor semi-permeable describes a material
with a water vapor permeance between 1 and 10 Perms.
Water vapor can pass through a semi-permeable
material but at a slow rate.
Building America Best Practices Series: Volume 4 – Builders and Buyers Handbook for
Improving New Home Efficiency, Comfort, and Durability in the Mixed-Humid Climate
Version 1, 9/2005 • APPENDIX II-4
Appendix II: Energy & Housing Glossary
Shading Coefficient (SC)
The ratio of the total solar heat admittance through
a given glazing product relative to the solar heat
admittance of double-strength, clear glass at normal
solar incidence (i.e., perpendicular to the glazing surface).
Vapor Diffusion
Solar Heat Gain Coefficient (SHGC)
SHGC measures how well a window blocks heat caused
by sunlight. The lower the SHGC rating the less solar
heat the window transmits. This rating is expressed as
a fraction between 0 and 1. The number is the ratio of
a window’s solar heat admittance compared to the total
solar heat available on the exterior window surface at
normal solar incidence (i.e., perpendicular to the
glazing surface).
Vapor Diffusion Retarder
Sone
A sound rating. Fans rated 1.5 sones and below are
considered very quiet.
W (watt)
One of two (Btu/h is the other) standard units of
measure for the rate at which energy is consumed by
equipment or the rate at which energy moves from
one location to another. It is also the standard unit of
measure for electrical power.
Supply ducts
The ducts in a forced air heating or cooling system that
supply heated or cooled air from the air conditioner to
conditioned spaces.
Thermal Boundary
The border between conditioned and unconditioned
space where insulation should be placed.
Thermostat
A control device that measures the temperature of the
air in a home or the water in a hot water tank and
activates heating or cooling equipment to cause the air
or water temperature to remain at a pre-specified value,
normally called the set point temperature.
Vapor diffusion describes the molecular process in
which vapor moves moisture from areas of higher vapor
pressure to areas of lower vapor pressure, and from areas
of greater temperature to areas of lesser temperature.
The function of a vapor diffusion retarder is to control
the entry of water vapor into building assemblies
through the mechanism of vapor diffusion. The
effectiveness of a vapor diffusion retarder is based on its
perm rating. See Perm and Vapor Diffusion.
Ventilation
The controlled movement of air into and out of a house.
Wet-Bulb Temperature
A measure of combined heat and humidity. At the same
temperature, air with less relative humidity has a lower
wet-bulb temperature. See Dry-Bulb Temperature.
Wind-Washing
Air movement due to increased pressure differences that
occur at the outside corners and roof eaves of buildings.
Wind-washing can have significant impact on thermal
and moisture movement and hence thermal and
moisture performance of exterior wall assemblies.
Ton(s) of Refrigeration
Units used to characterize the cooling capacity of air
conditioning equipment. One ton equals 12,000 Btu/h.
Xeriscaping
Landscaping that minimizes outdoor water use while
maintaining soil integrity and building aesthetics.
Typically includes emphasis on native plantings,
mulching, and no or limited drip/subsurface irrigation.
U-Value
Measures the rate at which heat flows or conducts
through a building assembly (wall, floor, ceiling, etc.).
The smaller the u-value the more energy efficient an
assembly and the slower the heat transfer. Window
performance labels include U-values (calling them Ufactors) to help in comparing across window products.
Zero Energy House
Any house that over time, averages out to net zero
energy consumption. A zero energy home may supply
more energy than it needs during peak demand,
typically using one or more solar energy strategies,
energy storage and/or net metering.
Building America Best Practices Series: Volume 4 – Builders and Buyers Handbook for
Improving New Home Efficiency, Comfort, and Durability in the Mixed-Humid Climate
Version 1, 9/2005 • APPENDIX II-5
Appendix II: Energy & Housing Glossary
Sources & Additional Information
• American Society of Heating, Refrigeration and Air Conditioning Engineers (ASHRAE). 1991.
Terminology of Heating Ventilation Air Conditioning and Refrigeration. Atlanta, GA.
• Building News. 2001. Construction Dictionary. BNi Publications, Los Angeles, CA.
• Florida Solar Energy Center (FSEC). Energy-Efficiency Economics Terms and Definitions available
on the Web at www.fsec.ucf.edu/bldg/fyh/ratings/e_terms.htm
• Lstiburek, Joseph. 2002. Builder’s Guide Hot and Humid Climates. Energy & Environmental Building
Association. Minneapolis, MN www.eeba.org
• Home Energy Magazine. 1997. “No-Regrets Remodeling: Creating a Comfortable, Healthy Home That Saves
Energy.” Energy Auditor & Retrofitter, Inc. Berkeley, CA.
Building America Best Practices Series: Volume 4 – Builders and Buyers Handbook for
Improving New Home Efficiency, Comfort, and Durability in the Mixed-Humid Climate
Version 1, 9/2005 • APPENDIX II-6
Appendix III
Code Notes
A meeting with the building department before construction is
well-advised. Should your code official need information in support
of the new techniques you may use in an energy-efficient home,
this appendix contains Web sites and a sample document that
may be helpful. A set of draft code notes are available on DOE’s
Building Energy Codes Resource Center. These draft documents
are written for codes officials, and provide a description of energy
efficiency techniques, citations to relevant codes, and guidance
for plan reviews and field inspections. The sample is the last one
on the list below and is entitled Rigid Board Insulation Installed
as Draft Stop in Attic Kneewall – Code Notes (Draft). Here is a
list of available code notes that should help assure your local
code official that the proposed techniques are both safe and in
compliance with the model codes. The code notes are available at
www.energycodes.gov/support/code_notes.stm.
• Single Top Plate
• No Headers in Nonbearing Walls
• Header Hangers in Bearing Walls
• Framing Floor Joists Spaced at 24 inches on Center
• Framing Studs Spaced at 24 inches on Center
• Open Spaces as Return-Air Options
• Details for Mechanically Vented Crawl Spaces
• Ventilation Requirements for Condensing Clothes Dryers
• Drywall Clips
• Rigid Board Insulation Installed as Draft Stop in Attic Kneewall
Building America Best Practices Series: Volume 4 – Builders and Buyers Handbook for
Improving New Home Efficiency, Comfort, and Durability in the Mixed-Humid Climate
Version 1, 9/2005 • APPENDIX III-1
Rigid Board Insulation Installed as Draft Stop in Attic Kneewall Code Notes (DRAFT)
Framing kneewall
Rigid board insulation (foam plastic) is an effective draft stop and also increases the R-value of the attic
kneewall if installed on the attic side of the kneewall, replacing the need for separate draft stop and insulation
products. The IRC requires foam plastic insulation to be protected against ignition by using fiberglass batt
insulation, gypsum board or other products that meet the flame and smoke density requirements. Foam
plastic products rated for flame and smoke density can be installed without such a protective covering.
Insulating attic kneewalls between a conditioned space with vaulted ceilings and the attic is important to
reduce energy loss through the wall, especially in the summer months. To be effective, the insulation installed
in the kneewalls must be supported so that it stays in contact with the gypsum board, and protected against
air moving through the insulation.
http://energycode.pnl.gov/cocoon/energy/
Page 1 of 3
Kneewall sheathing insulation to increase R-value to equal the outside wall.
Foam plastic insulation can be installed on the attic side of the attic kneewall (see Figure) to both act as a
draft stop between the conditioned house and the unconditioned attic and to increase the insulation R-value of
the attic kneewall. Installing such an insulating backing in the kneewall supports the fiberglass batt insulation
between framing members, replaces an air barrier, and adds insulating value to the attic kneewall.
Plan Review
1. Verify that plastic insulation called out on the construction detail meets the ASTM E 84 requirements for
flame spread and smoke development. Require manufacturer literature or an ICC Evaluation Service
report.
2. Verify that the insulation R-value of the foam plastic insulation called out on the building plans meets or
exceeds the R-value requirements called for on the energy code compliance documentation (only if credit
has been taken for the foam plastic insulation).
Field Inspection
1. Verify that the foam plastic insulation installed in the field is consistent with that called out on the building
plans.
2. Verify that the insulation R-value specified on the insulation meets or exceeds the R value called out on the
plans or documentation.
3. Verify that that sealant has been installed around the edges of the insulation and that any holes or
penetrations in the foam plastic insulation are sealed.
Code Citations
http://energycode.pnl.gov/cocoon/energy/
Page 2 of 3
IRC 2000, Section R318.2.3 and IRC 2003, Section R314.2.3
Within attics and crawlspaces, where entry is made only for service of utilities, foam plastics shall
be protected against ignition by 1 1/2-inch-thick (38 mm) mineral fiber insulation, 1/4-inch-thick (6.4
mm) wood structural panels, 3/8-inch (9.5 mm) particleboard, 1/4-inch (6.4 mm) hardboard, 3/8-inch
(9.5 mm) gypsum board, or corrosion resistant steel having a base metal thickness of 0.016 inch
(0.406 mm).
IRC 2000, Section R318.3
Plastic foam not meeting the requirements of Section R318.1 and R318.2 may be specifically
approved on the basis of one of the following approved tests: ASTM E 84, FM 4880, UL 1040,
ASTM E152, or UL 1715, or fire tests related to actual end-use configurations. The specific
approval may be based on the end use, quantity, location and similar considerations where such
tests would not be applicable or practical.
IRC 2003, Section R314.3
Plastic foam not meeting the requirements of Section R318.1 and R318.2 may be specifically
approved on the basis of one of the following approved tests: ASTM E 84, FM 4880, UL 1040,
NFPA 286, ASTM E152, or UL 1715, or fire tests related to actual end-use configurations. The
specific approval may be based on the end use, quantity, location and similar considerations where
such tests would not be applicable or practical.
http://energycode.pnl.gov/cocoon/energy/
Page 3 of 3
Appendix IV
Counties in the Mixed-Humid Climate
This section contains a list of all the counties, broken out by state, that are inside
the mixed-humid climate. You can find a master list for the entire country at
www.eere.energy.gov/buildings/building_america/pdfs/climate_regions_us_county_rev02.pdf
ALABAMA
MIXED-HUMID CLIMATE
Madison
Clay
Lawrence
Bibb
Marion
Cleburne
Lee
Blount
Marshall
Cleveland
Lincoln
Calhoun
Morgan
Conway
Logan
Chambers
Pickens
Craighead
Lonoke
Cherokee
Randolph
Crawford
Madison
Chilton
Shelby
Crittenden
Marion
Clay
St. Clair
Cross
Mississippi
Cleburne
Sumter
Dallas
Monroe
Colbert
Talladega
Desha
Montgomery
Coosa
Tallapoosa
Drew
Nevada
Cullman
Tuscaloosa
Faulkner
Newton
DeKalb
Walker
Franklin
Ouachita
Etowah
Winston
Fulton
Perry
Garland
Phillips
Fayette
ARKANSAS
Franklin
Arkansas
Grant
Pike
Greene
Ashley
Greene
Poinsett
Hale
Baxter
Hempstead
Polk
Jackson
Benton
Hot Spring
Pope
Jefferson
Boone
Howard
Prairie
Lamar
Bradley
Independence
Pulaski
Lauderdale
Calhoun
Izard
Randolph
Lawrence
Carroll
Jackson
Saline
Lee
Chicot
Jefferson
Scott
Limestone
Clark
Johnson
Searcy
Building America Best Practices Series: Volume 4 – Builders and Buyers Handbook for
Improving New Home Efficiency, Comfort, and Durability in the Mixed-Humid Climate
Version 1, 9/2005 • APPENDIX IV-1
Appendix IV:
Counties in the Mixed-Humid Climate
Sebastian
Clayton
Jackson
Towns
Sevier
Cobb
Jasper
Troup
Sharp
Columbia
Jefferson
Union
St. Francis
Coweta
Jones
Upson
Stone
Crawford
Lamar
Walker
Van Buren
Dade
Lincoln
Walton
Washington
Dawson
Lumpkin
Warren
White
DeKalb
Madison
Washington
Woodruff
Douglas
McDuffie
White
Yell
Elbert
Meriwether
Whitfield
Fannin
Monroe
Wilkes
Fayette
Morgan
Wilkinson
Floyd
Murray
Kent
Forsyth
Muscogee
Alexander
New Castle
Franklin
Newton
Bond
Sussex
Fulton
Oconee
Christian
GEORGIA
Gilmer
Oglethorpe
Clay
Baldwin
Glascock
Paulding
Clinton
Banks
Gordon
Pickens
Crawford
Barrow
Greene
Pike
Edwards
Bartow
Gwinnett
Polk
Effingham
Bibb
Habersham
Putnam
Fayette
Burke
Hall
Rabun
Franklin
Butts
Hancock
Richmond
Gallatin
Carroll
Haralson
Rockdale
Hamilton
Catoosa
Harris
Spalding
Hardin
Chattooga
Hart
Stephens
Jackson
Cherokee
Heard
Talbot
Jasper
Clarke
Henry
Taliaferro
Jefferson
DISTRICT OF COLUMBIA
District of Columbia
DELAWARE
Building America Best Practices Series: Volume 4 – Builders and Buyers Handbook for
Improving New Home Efficiency, Comfort, and Durability in the Mixed-Humid Climate
ILLINOIS
Version 1, 9/2005 • APPENDIX IV-2
Appendix IV:
Counties in the Mixed-Humid Climate
Johnson
Floyd
Barton
Hodgeman
Lawrence
Gibson
Bourbon
Jackson
Macoupin
Greene
Brown
Jefferson
Madison
Harrison
Butler
Johnson
Marion
Jackson
Chase
Kearny
Massac
Jefferson
Chautauqua
Kingman
Monroe
Jennings
Cherokee
Kiowa
Montgomery
Knox
Clark
Labette
Perry
Lawrence
Clay
Leavenworth
Pope
Martin
Coffey
Lincoln
Pulaski
Monroe
Comanche
Linn
Randolph
Ohio
Cowley
Lyon
Richland
Orange
Crawford
Marion
Saline
Perry
Dickinson
Marshall
Shelby
Pike
Doniphan
McPherson
St. Clair
Posey
Douglas
Meade
Union
Ripley
Edwards
Miami
Wabash
Scott
Elk
Montgomery
Washington
Spencer
Ellsworth
Morris
Wayne
Sullivan
Finney
Morton
White
Switzerland
Ford
Nemaha
Williamson
Vanderburgh
Franklin
Neosho
Warrick
Geary
Osage
Washington
Grant
Ottawa
Gray
Pawnee
INDIANA
Brown
Clark
KANSAS
Crawford
Allen
Greenwood
Pottawatomie
Daviess
Anderson
Harper
Pratt
Dearborn
Atchison
Harvey
Reno
Dubois
Barber
Haskell
Rice
Building America Best Practices Series: Volume 4 – Builders and Buyers Handbook for
Improving New Home Efficiency, Comfort, and Durability in the Mixed-Humid Climate
Version 1, 9/2005 • APPENDIX IV-3
Appendix IV:
Counties in the Mixed-Humid Climate
Riley
Breathitt
Graves
Logan
Rush
Breckinridge
Grayson
Lyon
Russell
Bullitt
Green
Madison
Saline
Butler
Greenup
Magoffin
Sedgwick
Caldwell
Hancock
Marion
Seward
Calloway
Hardin
Marshall
Shawnee
Campbell
Harlan
Martin
Stafford
Carlisle
Harrison
Mason
Stanton
Carroll
Hart
McCracken
Stevens
Carter
Henderson
McCreary
Sumner
Casey
Henry
McLean
Wabaunsee
Christian
Hickman
Meade
Washington
Clark
Hopkins
Menifee
Wilson
Clay
Jackson
Mercer
Woodson
Clinton
Jefferson
Metcalfe
Wyandotte
Crittenden
Jessamine
Monroe
Cumberland
Johnson
Montgomery
Adair
Daviess
Kenton
Morgan
Allen
Edmonson
Knott
Muhlenberg
Anderson
Elliott
Knox
Nelson
Ballard
Estill
Larue
Nicholas
Barren
Fayette
Laurel
Ohio
Bath
Fleming
Lawrence
Oldham
Bell
Floyd
Lee
Owen
Boone
Franklin
Leslie
Owsley
Bourbon
Fulton
Letcher
Pendleton
Boyd
Gallatin
Lewis
Perry
Boyle
Garrard
Lincoln
Pike
Bracken
Grant
Livingston
Powell
KENTUCKY
Building America Best Practices Series: Volume 4 – Builders and Buyers Handbook for
Improving New Home Efficiency, Comfort, and Durability in the Mixed-Humid Climate
Version 1, 9/2005 • APPENDIX IV-4
Appendix IV:
Counties in the Mixed-Humid Climate
Pulaski
Baltimore (city)
Callaway
Laclede
Robertson
Calvert
Camden
Lafayette
Rockcastle
Caroline
Cape Girardeau
Lawrence
Rowan
Carroll
Carroll
Lincoln
Russell
Cecil
Carter
Madison
Scott
Charles
Cass
Maries
Shelby
Dorchester
Cedar
McDonald
Simpson
Frederick
Christian
Miller
Spencer
Harford
Clay
Mississippi
Taylor
Howard
Cole
Moniteau
Todd
Kent
Cooper
Monroe
Trigg
Montgomery
Crawford
Montgomery
Trimble
Prince George’s
Dade
Morgan
Union
Queen Anne’s
Dallas
New Madrid
Warren
Somerset
Dent
Newton
Washington
St. Mary’s
Douglas
Oregon
Wayne
Talbot
Dunklin
Osage
Webster
Washington
Franklin
Ozark
Whitley
Wicomico
Gasconade
Pemiscot
Wolfe
Worcester
Greene
Perry
Henry
Pettis
Woodford
MISSOURI
LOUISIANA
Audrain
Hickory
Phelps
East Carroll
Barry
Howard
Platte
Morehouse
Barton
Howell
Polk
West Carroll
Bates
Iron
Pulaski
Benton
Jackson
Randolph
Allegany
Bollinger
Jasper
Ray
Anne Arundel
Boone
Jefferson
Reynolds
Baltimore
Butler
Johnson
Ripley
MARYLAND
Building America Best Practices Series: Volume 4 – Builders and Buyers Handbook for
Improving New Home Efficiency, Comfort, and Durability in the Mixed-Humid Climate
Version 1, 9/2005 • APPENDIX IV-5
Appendix IV:
Counties in the Mixed-Humid Climate
Saline
Clay
Pontotoc
Camden
Scott
Coahoma
Prentiss
Caswell
Shannon
DeSoto
Quitman
Catawba
St. Charles
Grenada
Scott
Chatham
St. Clair
Hancock
Sharkey
Cherokee
St. Francois
Harrison
Stone
Chowan
St. Louis
Holmes
Sunflower
Clay
St. Louis (city)
Humphreys
Tallahatchie
Cleveland
Ste. Genevieve
Issaquena
Tate
Craven
Stoddard
Itawamba
Tippah
Cumberland
Stone
Jackson
Tishomingo
Currituck
Taney
Jasper
Tunica
Dare
Texas
Kemper
Union
Davidson
Vernon
Lafayette
Washington
Davie
Warren
Lauderdale
Webster
Duplin
Washington
Leake
Winston
Durham
Wayne
Lee
Yalobusha
Edgecombe
Webster
Leflore
Yazoo
Forsyth
Wright
Lowndes
MISSISSIPPI
NORTH CAROLINA
Franklin
Madison
Alamance
Gaston
Alcorn
Marshall
Alexander
Gates
Attala
Monroe
Anson
Graham
Benton
Montgomery
Beaufort
Granville
Bolivar
Neshoba
Bertie
Greene
Calhoun
Newton
Bladen
Guilford
Carroll
Noxubee
Buncombe
Halifax
Chickasaw
Oktibbeha
Burke
Harnett
Choctaw
Panola
Cabarrus
Haywood
Clarke
Pearl River
Caldwell
Henderson
Building America Best Practices Series: Volume 4 – Builders and Buyers Handbook for
Improving New Home Efficiency, Comfort, and Durability in the Mixed-Humid Climate
Version 1, 9/2005 • APPENDIX IV-6
Appendix IV:
Counties in the Mixed-Humid Climate
Hertford
Rockingham
Middlesex
Beckham
Hoke
Rowan
Monmouth
Blaine
Hyde
Rutherford
Ocean
Bryan
Iredell
Sampson
Salem
Caddo
Jackson
Scotland
Union
Canadian
Johnston
Stanly
Jones
Stokes
NY New York
Cherokee
Lee
Surry
Bronx
Choctaw
Lenoir
Swain
Kings
Cleveland
Lincoln
Transylvania
Nassau
Coal
Macon
Tyrrell
New York
Comanche
Madison
Union
Queens
Cotton
Martin
Vance
Richmond
Craig
McDowell
Wake
Suffolk
Creek
Mecklenburg
Warren
Westchester
Custer
Montgomery
Washington
Moore
Wayne
Adams
Dewey
Nash
Wilkes
Brown
Ellis
Northampton
Wilson
Clermont
Garfield
Orange
Yadkin
Gallia
Garvin
Hamilton
Grady
Pamlico
NEW JERSEY
Carter
OHIO
Delaware
Pasquotank
Atlantic
Lawrence
Grant
Perquimans
Burlington
Pike
Greer
Person
Camden
Scioto
Harmon
Pitt
Cape May
Washington
Harper
Polk
Cumberland
OKLAHOMA
Haskell
Randolph
Essex
Adair
Hughes
Richmond
Gloucester
Alfalfa
Jackson
Robeson
Hudson
Atoka
Jefferson
Building America Best Practices Series: Volume 4 – Builders and Buyers Handbook for
Improving New Home Efficiency, Comfort, and Durability in the Mixed-Humid Climate
Version 1, 9/2005 • APPENDIX IV-7
Appendix IV:
Counties in the Mixed-Humid Climate
Johnston
Pushmataha
Darlington
Benton
Kay
Roger Mills
Dillon
Bledsoe
Kingfisher
Rogers
Edgefield
Blount
Kiowa
Seminole
Fairfield
Bradley
Latimer
Sequoyah
Florence
Campbell
Le Flore
Stephens
Greenville
Cannon
Lincoln
Tillman
Greenwood
Carroll
Logan
Tulsa
Kershaw
Carter
Love
Wagoner
Lancaster
Cheatham
Major
Washington
Laurens
Chester
Marshall
Washita
Lee
Claiborne
Mayes
Woods
Lexington
Clay
McClain
Woodward
Marion
Cocke
Marlboro
Coffee
McCurtain
PENNSYLVANIA
McIntosh
Bucks
McCormick
Crockett
Murray
Chester
Newberry
Cumberland
Muskogee
Delaware
Oconee
Davidson
Noble
Montgomery
Orangeburg
Decatur
Nowata
Philadelphia
Pickens
DeKalb
Okfuskee
York
Richland
Dickson
Saluda
Dyer
Oklahoma
SOUTH CAROLINA
Okmulgee
Abbeville
Spartanburg
Fayette
Osage
Aiken
Sumter
Fentress
Ottawa
Anderson
Union
Franklin
Pawnee
Calhoun
Williamsburg
Gibson
Payne
Cherokee
York
Giles
Pittsburg
Chester
Pontotoc
Pottawatomie
TENNESSEE
Grainger
Chesterfield
Anderson
Greene
Clarendon
Bedford
Grundy
Building America Best Practices Series: Volume 4 – Builders and Buyers Handbook for
Improving New Home Efficiency, Comfort, and Durability in the Mixed-Humid Climate
Version 1, 9/2005 • APPENDIX IV-8
Appendix IV:
Counties in the Mixed-Humid Climate
Hamblen
Meigs
Washington
Augusta
Hamilton
Monroe
Wayne
Bath
Hancock
Montgomery
Weakley
Bedford
Hardeman
Moore
White
Bedford (city)
Hardin
Morgan
Williamson
Bland
Hawkins
Obion
Wilson
Botetourt
Haywood
Overton
Henderson
Perry
Archer
Brunswick
Henry
Pickett
Clay
Buchanan
Hickman
Polk
Cooke
Buckingham
Houston
Putnam
Eastland
Buena Vista (city)
Humphreys
Rhea
Fannin
Campbell
Jackson
Roane
Grayson
Caroline
Jefferson
Robertson
Jack
Carroll
Johnson
Rutherford
Montague
Charles City
Knox
Scott
Palo Pinto
Charlotte
Lake
Sequatchie
Stephens
Charlottesville (city)
Lauderdale
Sevier
Wichita
Chesapeake (city)
Lawrence
Shelby
Wise
Chesterfield
Lewis
Smith
Young
Clarke
Lincoln
Stewart
Loudon
Sullivan
Accomack
Colonial Heights (city)
Macon
Sumner
Albemarle
Covington (city)
Madison
Tipton
Alexandria (city)
Craig
Marion
Trousdale
Alleghany
Culpeper
Marshall
Unicoi
Amelia
Cumberland
Maury
Union
Amherst
Danville (city)
McMinn
Van Buren
Appomattox
Dickenson
McNairy
Warren
Arlington
Dinwiddie
TEXAS
VIRGINIA
Building America Best Practices Series: Volume 4 – Builders and Buyers Handbook for
Improving New Home Efficiency, Comfort, and Durability in the Mixed-Humid Climate
Bristol (city)
Clifton Forge (city)
Version 1, 9/2005 • APPENDIX IV-9
Appendix IV:
Counties in the Mixed-Humid Climate
Emporia (city)
King and Queen
Petersburg (city)
Tazewell
Essex
King George
Pittsylvania
Virginia Beach (city)
Fairfax
King William
Poquoson (city)
Warren
Fairfax (city)
Lancaster
Portsmouth (city)
Washington
Falls Church (city)
Lee
Powhatan
Waynesboro (city)
Fauquier
Lexington (city)
Prince Edward
Westmoreland
Floyd
Loudoun
Prince George
Williamsburg (city)
Fluvanna
Louisa
Prince William
Winchester (city)
Franklin
Lunenburg
Pulaski
Wise
Franklin (city)
Lynchburg (city)
Radford (city)
Wythe
Frederick
Madison
Rappahannock
York
Fredericksburg (city)
Manassas (city)
Richmond
Galax (city)
Manassas Park (city)
Richmond (city)
Berkeley
Giles
Martinsville (city)
Roanoke
Boone
Gloucester
Mathews
Roanoke (city)
Braxton
Goochland
Mecklenburg
Rockbridge
Cabell
Grayson
Middlesex
Rockingham
Calhoun
Greene
Montgomery
Russell
Clay
Greensville
Nelson
Salem (city)
Gilmer
Halifax
New Kent
Scott
Jackson
Hampton (city)
Newport News (city)
Shenandoah
Jefferson
Hanover
Norfolk (city)
Smyth
Kanawha
Harrisonburg (city)
Northampton
Southampton
Lincoln
Henrico
Northumberland
Spotsylvania
Logan
Henry
Norton (city)
Stafford
Mason
Highland
Nottoway
Staunton (city)
McDowell
Hopewell (city)
Orange
Suffolk (city)
Mercer
Isle of Wight
Page
Surry
Mingo
James City
Patrick
Sussex
Monroe
Building America Best Practices Series: Volume 4 – Builders and Buyers Handbook for
Improving New Home Efficiency, Comfort, and Durability in the Mixed-Humid Climate
WEST VIRGINIA
Version 1, 9/2005 • APPENDIX IV-10
Appendix IV:
Counties in the Mixed-Humid Climate
Morgan
Pleasants
Putnam
Ritchie
Roane
Tyler
Wayne
Wirt
Wood
Wyoming
Building America Best Practices Series: Volume 4 – Builders and Buyers Handbook for
Improving New Home Efficiency, Comfort, and Durability in the Mixed-Humid Climate
Version 1, 9/2005 • APPENDIX IV-11
Appendix V
Web Site References
This section lists all of the Web sites referenced in the Best Practices Series. It is intended to help readers in two ways.
First, those interested in finding a reference without going back through the text may do so. Secondly, this list will
be included as a live portion of the Building America Web site. The list will be updated periodically to incorporate
changes in links. In this way, readers may visit the Building America Web site and click on a current link rather than
monitoring and tracking down links on their own. The links are listed by chapter and for the Designers and Trades
chapters, also by secondary headings.
INTRODUCTION
www.buildingamerica.gov
Building America is a private/public partnership that
develops energy solutions for new and existing homes.
HOMEOWNERS
www.ornl.gov/sci/roofs+walls/insulation/ins_16.html
Easy to use R-value recommendation form uses input such
as house status, fuel type and zip code to form analysis
for installation.
www.fanniemae.com
Known for energy-efficient loans, Fannie Mae is the
nation’s largest source of funding for mortgages.
www.natresnet.org
The Residential Energy Services Network’s (RESNET)
mission is to improve the energy efficiency of the nation’s
housing stock and to qualify more families for home
ownership by expanding the national availability of
mortgage financing options and home energy ratings.
www.hud.gov/offices/hsg/sfh/eem/energy-r.cfm
Energy Efficient Mortgages Programs helps to achieve
national energy-efficiency goals (and reduce pollution)
as well as provide better housing for people who might
not otherwise be able to afford it.
www.eflhome.com/index.jsp
The Environments for Living Program’s energy use and
comfort guarantees promise potential savings, comfort
and durability that were never thought possible.
www.us-gf.com/engineered.asp
An Engineered For Life® home is an energy-efficient home
that has been designed, built and tested according to the
principles of building science for optimal safety, durability,
affordability, and comfort.
www.artistichomessw.com/guarantee.htm
Artistic Homes clearly marks every new home floor-plan
with the annual amount of space heating and cooling
energy that is expected to be used. Artistic Homes’
guarantee: If your actual space heating and cooling
usage is less than guaranteed, you pay less.
www.energystar.gov
ENERGY STAR is a government-backed program helping
businesses and individuals protect the environment
through superior energy efficiency.
www.buildingamerica.gov
Building America is a private/public partnership that
develops energy solutions for new and existing homes.
www.housingzone.com
Housingzone.com contains content for builders, remodelers,
architects, suppliers, consumers, and manufacturers.
The Web site includes material from Professional Builder,
Professional Remodeler, and Custom Builder magazines
www.buildiq.com
BuildIQ, a provider of online training for construction
professionals, has an extensive resource list on best
practices in homebuilding for consumers in its Best
Practices area of this site.
MANAGERS
www.energystar.gov
ENERGY STAR is a government-backed program helping
businesses and individuals protect the environment
through superior energy efficiency.
www.housingzone.com
Housingzone.com contains content for builders,
remodelers, architects, suppliers, consumers, and
manufacturers. The Web site includes material from
Professional Builder, Professional Remodeler, and
Custom Builder magazines
Building America Best Practices Series: Volume 4 – Builders and Buyers Handbook for
Improving New Home Efficiency, Comfort, and Durability in the Mixed Humid Climate
Version 1, 9/2005 • APPENDIX V-1
Appendix V: Web Site References
www.energyvideos.com
The California Energy Commission Web site contains
brief videos explaining how building homes beyond the
levels required by code is good for business. Other videos
provide training on meeting California code and installing
energy efficient building measures.
MARKETERS
www.energystar.gov
ENERGY STAR is a government-backed program helping
businesses and individuals protect the environment
through superior energy efficiency.
www.nahbrc.org/tertiaryR.asp?CategoryID=1705&
DocumentID=3404
The EnergyValue Housing Award guide is a compilation
of best practices of winners of the national EnergyValue
Housing Award. It can be purchased from the NAHB
Research Center Web site.
www.efficientwindows.org/index.cfm
The Efficient Windows Collaborative Web site provides
unbiased information on the benefits of energyefficient windows, descriptions of how they work, and
recommendations for their selection and use.
www.builderonline.com/article-builder.asp?channelid=
55&articleid=375&qu=consumer+survey
Builder Online Web site presents a survey that reveals
builders and buyers may be on different wavelengths
when it comes to the choice of products and materials.
www.housingzone.com
Housingzone.com contains content for builders, remodelers,
architects, suppliers, consumers, and manufacturers.
The Web site includes material from Professional Builder,
Professional Remodeler, and Custom Builder magazines
SITE PLANNERS
www.efficientwindows.org
The Efficient Windows Collaborative Web site provides
unbiased information on the benefits of energyefficient windows, descriptions of how they work, and
recommendations for their selection and use.
www.lid-stormwater.net
Sponsored by the EPA, this Web site contains information
and low-impact urban design tools to help developers and
watershed managers.
www.southface.org/home/sfpubs/large-pubs/
Sustainable_community_development.pdf
Located in Atlanta, Southface Energy Institute is a 501(c)(3)
nonprofit corporation that promotes sustainable homes,
workplaces and communities through education, research,
advocacy and technical assistance. This URL contains a
PDF version of the referenced document.
www.eeba.org
The Energy and Environmental Building Association (EEBA)
promotes the awareness, education and development of
energy efficient, environmentally responsible buildings and
communities. The EEBA Web site includes a bookstore
where the referenced document may be purchased.
www.fed.us/ne/newtown_square/publications/
technical_reports/pdfs/scanned/gtr1869.pdf
PDF version of the Chicago’s Urban Forest Ecosystem:
Results of the Chicago Urban Forest Climate Project
from the U.S. Department of Agriculture’s Northeastern
Research Station.
www.BuilderBooks.com
Purchasing Web site of books for the builder, bookstore of
the National Association of Home Builders.
www.SBICouncil.org
Sustainable Buildings Industry Council (SBIC) is an
independent, nonprofit organization whose mission is to
advance the design, affordability, energy performance, and
environmental soundness of America’s buildings.
www.fsec.ucf.edu/bldg/pubs/pf363/index.htm
The Florida Solar Energy Center presents an article on
housing in rural areas that could result in changes to local
climate and increased energy bills.
www.lid-stormwater.net
Sponsored by the EPA, this Web site contains information
and low-impact urban design tools to help developers and
watershed managers.
www.cabq.gov/waterconservation/xeric.html
The City of Albuquerque’s Web site provides information
on xeriscaping strategies for dry climates.
http://xeriscape.org
Xeriscape Colorado, Inc. is a non-profit membership group
promoting creative approaches to water conserving
landscapes.
www.sustainabledesignguide.umn.edu/MSDG/site.html
A guide to sustainable development developed by the
University of Minnesota.
Building America Best Practices Series: Volume 4 – Builders and Buyers Handbook for
Improving New Home Efficiency, Comfort, and Durability in the Mixed Humid Climate
Version 1, 9/2005 • APPENDIX V-2
Appendix V: Web Site References
http://hort.ufl.edu
A guide to environmentally friendly landscaping developed
by the University of Florida.
DESIGNERS
Building Science and the Systems Approach
www.buildingamerica.gov
Building America is a private/public partnership that
develops energy solutions for new and existing homes.
www.fsec.ucf.edu/bldg/science/basics/index.htm
The Florida Solar Energy Center presents the basics of
building science for more efficient and powerful products.
www.nbnnews.com
National Association of Home Builders offers an online
newsletter center with a tool for accessing back issues of
the publications.
www.natresnet.org
The Residential Energy Services Network’s (RESNET)
mission is to improve the energy efficiency of the nation’s
housing stock and to qualify more families for home
ownership by expanding the national availability of
mortgage financing options and home energy ratings.
www.energycodes.gov
A Web site describing U.S. DOE’s Energy Codes Program.
www.ibacos.com/bestprac.html
IBACOS, a Building America team member, offers
guidelines, including graphic details, for designing and
implementing quality construction practices, based on
IBACOS’ research and experience working in the field
with builders.
Foundation Measures
www.epa.gov/199/iaq/radon/images/buildradonout.pdf
A guide to building radon-resistant homes is outlined
by the Office of Radiation and Indoor Air at the U.S.
Environmental Protection Agency.
www.epa.gov/radon/zonemap.html
Environmental Protection Agency’s map of radon zones
includes all states with a breakdown of zone information
classified by region.
www.epa.gov/iaq/whereyoulive.html
State and regional contact information for indoor air
quality and radon control.
www.buildingscience.com/resources/articles
/24-27_Yost_for_author.pdf
An Article by Dr. Nathan Yost, M.D. is presented
by buildingscience.com and offers information on
conditioned, unvented crawl spaces.
www.buildingscience.com/housesthatwork
/hothumid/montgomery.htm
The Building Science Corporation leads a Building America
team. Houses that work provides drawings, specifications,
materials characteristics for sample housing types in five
climate zones.
www.ibacos.com/ghome/Aug04/Aug2004_Water.html
This article from IBACOS discusses best practices for
foundations in areas with expansive soils.
www.ibacos.com/ghome/Jan04/Jan_BPWebBasements.html
www.ibacos.com/ghome/Jan04/bestpractice.pdf
www.ibacos.com/pubs/Newsletter-July02.pdf#page=3
These articles from IBACOS present best practices for
designing and building quality foundation systems.
Site – Drainage, Pest Control, and Landscaping
Structural Moisture Control
www.uky.edu/Agriculture/Entomology/entfacts.htm
www.eere.energy.gov/buildings/info/documents
/pdfs/28600.pdf
University of Kentucky Entomology site has a block
of options to navigate which include field crops, fruit,
livestock, misc., landscape plants, vegetables, home
and health and a list of facts.
www.eere.energy.gov/consumerinfo/factsheets/
landscape.html
This Department of Energy’s Web site includes information
for energy efficiency landscaping.
The Department of Energy presents a Technology Fact
Sheet on how to select and install housewrap and other
types of weather-resistive barriers.
www.fema.gov
The Federal Energy Management Agency’s mission is to
prepare the nation for all hazards and effectively manage
federal response and recovery efforts following any
national incident.
Building America Best Practices Series: Volume 4 – Builders and Buyers Handbook for
Improving New Home Efficiency, Comfort, and Durability in the Mixed Humid Climate
Version 1, 9/2005 • APPENDIX V-3
Appendix V: Web Site References
www.blueprintforsafety.org
Florida Alliance for Safe Homes’ building guidelines for
hazardous areas.
www.ibhs.org
The Institute for Business and Home Safety has building
guidelines and public information for surviving disasters.
www.buildingcodeonline.com
The Miami-Dade County Building Code Compliance
Office offers a searchable database of building materials
approved for high-wind locations.
www.ibacos.com/ghome/March03/
march03_bestpractices_roofflashing.html
This document provides guidelines on roof flashing.
www.ibacos.com/ghome/Aug03/Sug2003_bp_brick.html
This article by IBACOS provides solutions for moisture
issues in brick veneer homes.
www.ibacos.com/ghome/Winter05/
winter05_bestpractices_drainage_plane.html
This article by IBACOS discusses the importance of
providing a continuous drainage plane.
www.eere.energy.gov/weatherization/hazard_workshop.html
U.S. DOE offers a training program for home inspectors to
identify hazards.
www.buildingscience.com/resources/walls
/brick_stucco_housewraps.pdf
Website provides information on housewrap and building
paper performance behind brick and stucco.
www.eere.energy.gov/buildings/documents/pdfs/28600.pdf
The Department of Energy presents a Technology Fact
Sheet on how to select and install housewrap and other
types of weather-resistive barriers.
www.buildingscience.com/housesthatwork
/buildingmaterials.htm
The Building Science Corporation leads a Building America
team. Houses that work provides drawings, specifications,
materials characteristics for sample housing types in five
climate zones.
www.buildingscience.com/resources/walls
/problems_with_housewraps.htm
The function of a housewrap and the problems associated
with them are laid out in a well written article on
buildingscience.com.
www.cdnarchitect.com
Canadian Architect is a magazine that offers information
for architects and other professionals in related fields.
www.nahbrc.org/docs/mainnav/moistureandleaks
/792_moisture.pdf
This document from the NAHB Research Center provides
information to help control leaks.
www.eeba.org/bookstore
The Energy and Environmental Building Association (EEBA)
promotes the awareness, education and development of
energy efficient, environmentally responsible buildings and
communities. The EEBA Web site includes a bookstore
where the referenced document may be purchased.
www.buildingscience.com/housesthatwork/airsealing.htm
The Building Science Corporation leads a Building America
team. Houses that Work provides drawings, specifications,
materials characteristics for sample housing types in five
climate zones.
www.eere.energy.gov/buildings/info/documents/
pdfs/26448.pdf
The Department of Energy presents a Technology Fact
Sheet on the benefits of sealing air leaks to save energy.
Structural Thermal Performance
www.ornl.gov/sci/roofs+walls/insulation/ins_08.html
What kind of insulation should you buy? An insulation fact
sheet presented by the Department of Energy clarifies.
www.fsec.ucf.edu/bldg/pubs/rbs/index.htm
The FPC Monitoring project has evaluated radiant barrier
systems (RBS) as a new potential DSM program.
www.ornl.gov/sci/roofs+walls/radiant/rb_01.html
Provides descriptions and a fact sheet about radiant barriers.
Building America Best Practices Series: Volume 4 – Builders and Buyers Handbook for
Improving New Home Efficiency, Comfort, and Durability in the Mixed Humid Climate
Version 1, 9/2005 • APPENDIX V-4
Appendix V: Web Site References
www.energystar.gov
ENERGY STAR is a government-backed program helping
businesses and individuals protect the environment
through superior energy efficiency.
www.ornl.gov/sci/roofs+walls/insulation/ins_16.html
Easy to use R-Value recommendation form uses input such
as house status, fuel type and zip code to form analysis
for installation.
www.eere.energy.gov/consumerinfo/energy_savers
/r-value_map.html
A detailed map represents recommended total R-Values
for existing houses according to the Department of Energy.
www.buildingscience.com/housesthatwork
/advancedframing/default.htm
Advanced framing details the Building Science Corporation.
www.buildingscience.com/housesthatwork/hothumid/
orlando.htm
The Building Science Corporation leads a Building
America team. Houses that work provides drawings,
specifications, materials characteristics for sample
housing recommendations in five climate zones.
www.nfrc.org
National Fenestration Rating Council (NFRC) is a non-profit,
public/private organization created by the window, door
and skylight industry which provides consistent ratings on
window, door and skylight products.
www.efficientwindows.org/index.cfm
The Efficient Windows Collaborative Web site provides
unbiased information on the benefits of energyefficient windows, descriptions of how they work, and
recommendations for their selection and use.
www.susdesign.com/sunangle/
Input and output variables form a calculation tool for sun angles.
www.wunderground.com
A weather forecasting and data Web site.
www.susdesign.com/overhang/index.html
Overhang design tool allows the shading performance of
window overhangs to be easily analyzed using precise
calculations and positioning.
www.eere.energy.gov/buildings/index.cfm?flash=yes
DOE’s Building Technologies Program works to improve
the energy efficiency of our nation’s buildings through
innovative new technologies and better building practices.
Site includes research and regulatory activities.
www.sbse.org/resources/sac/index.htm
Presented by the Society of Building Science Educators,
this Web page offers general information and purchasing
details on the sun angle calculator.
www.ibacos.com/ghome/March04/Mar_BPRoofs.html
This article by IBACOS discusses best practices for an
airtight, insulated roof system, and provides specific
solutions insulating cathedral roofs.
www.ibacos.com/ghome/March04/Mar_Tech_
VentedAttics.html
This article by IBACOS discusses insulating vented attics
for performance.
www.ibacos.com/ghome/Oct03/duct.html
This article by IBACOS discusses controlling condensation
on duct systems.
Heating, Ventilating and Air Conditioning
www.acca.org
From technical topics to management tips, the Air
Conditioning Contractors of America provide a wealth
of knowledge and information useful for the successful
contracting business, including selection and sizing
manuals.
www.energy.ca.gov/2005publications/CEC-400-2005
005/CEC-400-2005-005-CMF.pdf
California Energy Commission’s 2005 Residential
Compliance Manual
www.eere.energy.gov/buildings/appliance_standards/
DOE’s tips on saving energy and money at home.
www.energystar.gov/index.cfm?c=appliances.pr_appliances
A list of appliances with an ENERGY STAR rating can be
found on this Web page.
www.buildingscience.com/resources/mechanical
/air_distribution.pdf
Examples of HVAC systems with detailed information
on the energy and economic benefit is provided by
buildingscience.com.
Building America Best Practices Series: Volume 4 – Builders and Buyers Handbook for
Improving New Home Efficiency, Comfort, and Durability in the Mixed Humid Climate
Version 1, 9/2005 • APPENDIX V-5
Appendix V: Web Site References
www.ibacos.com/pubs/Newsletter-July02.pdf
This article by IBACOS discusses best practices for
achieving thermal comfort.
www.ibacos.com/ghome/March03/march03_cover.html
This article by IBACOS presents HVAC optimization strategies.
www.ibacos.com/ghome/June03/wtrhtr.html
This article by IBACOS discusses sizing strategies for
water heaters.
www.buildingscience.com/resources/mechanical
/conditioning_air.pdf
The Building Science Consortium’s Houston study of
dehumidifiers (BSC 2002) is available on the referenced
Web page.
http://ducts.lbl.gov/Publications/lbl-41118.pdf
A technical report on duct sealants can be found on the
referenced Web page.
www.homeenergy.org/archive/hem.dis.anl.gov/
eehem/98/9807.html
The magazine, Home Energy, contains an article describing
duct sealants.
www.fsec.ucf.edu/bldg/baihp//pubs/interior_ducts.pdf
Web page offers information on designing and building an
interior chase.
www.buildingscience.com/resources/roofs
/unvented_roof_summary_article.pdf
The linked article summarizes the various papers on
unvented conditioned cathedralized attics found on the site.
www.buildingscience.com/housesthatwork/hothumid
/montgomery.htm
The Building Science Corporation leads a Building America
team. Houses that work provides drawings, specifications,
materials characteristics for sample housing types in five
climate zones.
www.energystar.gov/ia/new_homes/features
/DuctInsulation1-17-01.pdf
Recommendations for insulation levels for ducts in uncondi
tioned spaces can be found on this site.
www.buildingscience.com/resources/moisture
/relative_humidity_0402.pdf
Relative humidity discussion.
Mechanicals Management and Appliances
www.toolbase.org
This Web site contains PATH’s listing of building
technologies, including air admittance vents and
manifold water distribution systems. PATH stands for the
Partnership for Advanced Housing Technology. To reach
information about air admittance valves after reaching
the Web site select new building technologies, plumbing,
distribution systems, and finally, air admittance vents.
www.gamanet.org
GAMA, the Gas Appliance Manufacturers Association, is a
national trade association of manufacturers of residential,
commercial and industrial appliances and equipment,
components and related products.
www.energy.state.or.us/res/tax/appheat.htm
A list of high-efficiency water heaters that qualify for state
tax credits is presented by The Oregon Department of
Energy. Only Oregon taxpayers qualify for the credits.
www.pnl.gov/cfldownlights/
The purpose of the Residential Recessed Downlights
Project is to increase the availability and use of highly
energy-efficient recessed downlight fixtures for homes.
Website provides highly energy-efficient recessed
downlight fixtures that have undergone stringent testing
available for purchase.
www.eere.energy.gov/consumerinfo/energy_savers
/appliances.html
A list of major appliances with high-energy efficiency
standards are documented by the Department of Energy.
Only appliances in the top one-third of the DOE Energy
Guide rating scale should be selected.
www.ibacos.com/hpl.html
Designed for builders, this High Performance Lighting Guide
developed by IBACOS discusses high performance lighting
strategies for new homes.
Web Sites Listed Only in Designers Chapter References
www.buildingscience.com/resources/mechanical
/advanced_space_conditioning.pdf
A Building Science Corporation document discussing
system tradeoffs between building envelopes and heating
and ventilation equipment.
www.buildingamerica.gov
Building America is a private/public partnership that
develops energy solutions for new and existing homes.
Building America Best Practices Series: Volume 4 – Builders and Buyers Handbook for
Improving New Home Efficiency, Comfort, and Durability in the Mixed Humid Climate
Version 1, 9/2005 • APPENDIX V-6
Appendix V: Web Site References
www.wwnorton.com/npb/welcome.htm
Norton Professional Books offers an online bookstore in
subjects such as architecture/design.
www.eere.energy.gov/buildings/documents/pdfs/28600.pdf
The Department of Energy presents a Technology Fact
Sheet on how to select and install housewrap and other
types of weather-resistive barriers.
www.eeba.org/bookstore
The Energy and Environmental Building Association (EEBA)
promotes the awareness, education and development of
energy efficient, environmentally responsible buildings and
communities. The EEBA Web site includes a bookstore
where the referenced document may be purchased.
www.fsec.ucf.edu/bldg/baihp/pubs/interior_ducts.pdf
www.buildingscience.com/resources/articles
/24-27_Yost_for_author.pdf
An Article by Dr. Nathan Yost, M.D. is presented
by buildingscience.com and offers information on
conditioned, unvented crawl spaces.
www.eere.energy.gov/buildings/index.cfm?flash=yes
DOE’s Building Technologies Program works to improve
the energy efficiency of our nation’s buildings through
innovative new technologies and better building practices.
Site includes research and regulatory activities.
www.energystar.gov/index.cfm?c=bop.pt_bop_index
ENERGY STAR is a government-backed program helping
businesses and individuals protect the environment
through superior energy efficiency. Index includes builder
option packages referenced by state.
Web page offers information on designing and building an
interior chase.
www.fsec.ucf.edu/bldg/pubs/rbs/index.htm
The FPC Monitoring project has evaluated radiant barrier
systems (RBS) as a new potential DSM program.
www.buildingscience.com/resources/mechanical
/air_conditioning_equipment_efficiency.pdf
A Building Science Corporation document providing
procedures for refrigeration system installation and start up.
www.homeenergy.org/898ductape.title.html
Home Energy Magazine contains an article describing
duct sealants.
www.SBICouncil.org
Sustainable Buildings Industry Council (SBIC) is an
independent, nonprofit organization whose mission is to
advance the design, affordability, energy performance,
and environmental soundness of America’s buildings.
www.energystar.gov/ia/new_homes/features
/DuctInsulation1-17-01.pdf
Recommendations for insulation levels for ducts in
unconditioned spaces in the hot and humid climate can
be found on this site.
www.fsec.ucf.edu/bldg/pubs/ACsize/index.htm
The Florida Solar Energy Center presents a document
on how air conditioning systems are sized.
http://ducts.lbl.gov/Publications/lbl-41118.pdf
A technical report on duct sealants can be found on the
referenced Web page.
SITE SUPERVISORS
www.comfortwise.com/installationprotocols.shtml
ConSol leads a Building America team and developed the
statements of work listed on this Web site for builders in
California. These statements of work can be incorporated
into contracts.
www.thebii.org/rpsw.asp
Statements of work developed by ConSol for builders
in California are also available on this Web site. These
statements of work can be incorporated into contracts.
www.energycodes.gov/support/code-notes.stm
DOE’s building codes program provides draft Code Notes
to help code officials
www.buildingamerica.gov
Building America is a private/public partnership that
develops energy solutions for new and existing homes.
www.eeba.org
The Energy and Environmental Building Association (EEBA)
promotes the awareness, education and development of
energy efficient, environmentally responsible buildings and
communities. The EEBA Web site includes a bookstore
where the referenced document may be purchased.
www.buildingscience.com/workshops/default.htm
Building Science Corporation offers workshops and
seminars that are tailored towards building professionals.
Building America Best Practices Series: Volume 4 – Builders and Buyers Handbook for
Improving New Home Efficiency, Comfort, and Durability in the Mixed Humid Climate
Version 1, 9/2005 • APPENDIX V-7
Appendix V: Web Site References
www.nahbrc.org
The National Association of Home Builders Research
Center leads a Building America team and conducts
training for builders. This Web site contains articles,
schedules, and links describing technical materials and
training opportunities.
www.southface.org
Located in Atlanta, Southface Energy Institute is a 501(c)(3)
nonprofit corporation that promotes sustainable homes,
workplaces and communities through education, research,
advocacy and technical assistance.
www.ibacos.com
IBACOS, Inc. (Integrated Building and Construction
Solutions) was created to help enable the homebuilding
industry to deliver Quality Homes®—homes of inherently
higher performance that are safe, healthy, durable,
comfortable and efficient.
www.acca.org
From technical topics to management tips, the Air
Conditioning Contractors of America provide a wealth
of knowledge and information useful for the successful
contracting business, including selection and
sizing manuals.
www.installationmastersusa.com
This Web site describes a window installation training
program developed by the American Architectural
Manu-facturers Association.
www.energyvideos.com
The California Energy Commission Web site contains
brief videos explaining how building homes beyond the
levels required by code is good for business. Other videos
provide training on meeting California code and installing
energy efficient building measures.
www.pathnet.org/sp.asp?id=10787
This Web site contains training videos available from
PATH TV. PATH stands for the Partnership for Advancing
Technology in Housing.
www.natresnet.org
The Residential Energy Services Network’s (RESNET)
mission is to improve the energy efficiency of the nation’s
housing stock and to qualify more families for home
ownership by expanding the national availability of
mortgage financing options and home energy ratings.
http://hem.dis.anl.gov/eehem/00/001105.html
Home Energy Magazine explores HVAC questions.
TRADES
Slab Insulation - Cold Climates
www.eere.energy.gov/buildings/info/documents/
pdfs/29237.pdf
The Department of Energy presents a Technology Fact
Sheet on how to improve comfort and save energy in
homes with slab-on-grade floors.
www.epa.gov/199/iaq/radon
A guide to building radon-resistant homes is outlined
by the Office of Radiation and Indoor Air at the U.S.
Environmental Protection Agency.
www.southface.org/web/resources&services/
publications/factsheets/29_insulatefloors4PDF.pdf
Located in Atlanta, Southface Energy Institute is a 501(c)(3)
nonprofit corporation that promotes sustainable homes,
workplaces and communities through education, research,
advocacy and technical assistance. This URL contains a
PDF version of the referenced document.
www.southface.org/web/resources&services/
publications/factsheets/30_radonresistantconst.pdf
Located in Atlanta, Southface Energy Institute is a 501(c)(3)
nonprofit corporation that promotes sustainable homes,
workplaces and communities through education, research,
advocacy and technical assistance. This URL contains a
PDF version of the referenced document.
www.buildingscience.com/housesthatwork
The Building Science Corporation leads a Building America
team. Houses that Work provides drawings, specifications,
materials characteristics for sample housing types in five
climate zones.
Basement & Conditioned (Unvented)
Crawlspace Insulation
www.buidingamerica.gov
Building America is a private/public partnership that
develops energy solutions for new and existing homes.
www.eeba.org/bookstore
The Energy and Environmental Building Association (EEBA)
promotes the awareness, education and development of
energy efficient, environmentally responsible buildings and
communities. The EEBA Web site includes a bookstore
where the referenced document may be purchased.
Building America Best Practices Series: Volume 4 – Builders and Buyers Handbook for
Improving New Home Efficiency, Comfort, and Durability in the Mixed Humid Climate
Version 1, 9/2005 • APPENDIX V-8
Appendix V: Web Site References
www.epa.gov/199/iaq/radon
A guide to building radon-resistant homes is outlined
by the Office of Radiation and Indoor Air at the U.S.
Environmental Protection Agency.
Housewraps
www.southface.org/home/sfpubs/techshts
/8_airsealing.pdf
Located in Atlanta, Southface Energy Institute is a 501(c)(3)
nonprofit corporation that promotes sustainable homes,
workplaces and communities through education, research,
advocacy and technical assistance. This URL contains a
PDF version of the referenced document.
www.eere.energy.gov/buildings/info/documents/
pdfs/26448.pdf
The Department of Energy presents a Technology Fact
Sheet on the benefits of sealing air leaks to save energy.
http://construction.tyvek.com/en/productServices
/HomeWrap/index.shtml
Tyvek® HomeWrap® is a weatherization membrane that
provides a protective layer under a home’s siding and over
the sheathing.
www.cdnarchitect.com
Canadian Architect is a magazine that offers information
for architects and other professionals in related fields.
Window Flashing
www.eeba.org
The Energy and Environmental Building Association (EEBA)
promotes the awareness, education and development of
energy efficient, environmentally responsible buildings and
communities. The EEBA Web site includes a bookstore
where the referenced document may be purchased.
www.eere.energy.gov/buildings/info/documents/
pdfs/28600.pdf
The Department of Energy presents a Technology Fact
Sheet on how to select and install housewrap and other
types of weather-resistive barriers.
www.ibacos.com/ghome/Jan03/jan03_windows.html
This document from IBACOS present window flashing and
installation guidelines.
Air Sealing – Plumbing
www.eeba.org
The Energy and Environmental Building Association (EEBA)
promotes the awareness, education and development of
energy efficient, environmentally responsible buildings and
communities. The EEBA Web site includes a bookstore
where the referenced document may be purchased.
www.eere.energy.gov/buildings/info/documents/
pdfs/26448.pdf
The Department of Energy presents a Technology Fact
Sheet on the benefits of sealing air leaks to save energy.
www.toolbase.org
This Web site contains PATH’s listing building
technologies, including air admittance vents and
manifold water distribution systems. PATH stands for the
Partnership for Advanced Housing Technology. To reach
information about air admittance valves after reaching
the Web site select new building technologies, plumbing,
distribution systems, and finally, air admittance vents.
Electrical Air Sealing
www.eeba.org
The Energy and Environmental Building Association (EEBA)
promotes the awareness, education and development of
energy efficient, environmentally responsible buildings and
communities. The EEBA Web site includes a bookstore
where the referenced document may be purchased.
www.eere.energy.gov/buildings/info/documents
/pdfs/26448.pdf
The Department of Energy presents a Technology Fact
Sheet on the benefits of sealing air leaks to save energy.
Air Sealing Glossary
www.eere.energy.gov/buildings/info/documents
/pdfs/26448.pdf
The Department of Energy presents a Technology Fact
Sheet on the benefits of sealing air leaks to save energy.
Masonry Construction
www.eeba.org
The Energy and Environmental Building Association (EEBA)
promotes the awareness, education and development of
energy efficient, environmentally responsible buildings and
communities. The EEBA Web site includes a bookstore
where the referenced document may be purchased.
Building America Best Practices Series: Volume 4 – Builders and Buyers Handbook for
Improving New Home Efficiency, Comfort, and Durability in the Mixed Humid Climate
Version 1, 9/2005 • APPENDIX V-9
Appendix V: Web Site References
Radiant Barriers
APPENDIX II
www.eere.energy.gov/consumerinfo/refbriefs/bc7.html
www.fsec.ucf.edu/bldg/fyh/ratings/e_terms.htm
The Department of Energy presents an information fact
sheet on radiant barriers.
www.southface.org/home/sfpubs/techshts
/14radiantbarriers.pdf
Located in Atlanta, Southface Energy Institute is a 501(c)(3)
nonprofit corporation that promotes sustainable homes,
workplaces and communities through education, research,
advocacy and technical assistance. This URL contains a
PDF version of the referenced document.
www.southface.org/home/sfpubs/techshts
/25_insulateceilings_4pdf.pdf
Located in Atlanta, Southface Energy Institute is a 501(c)(3)
nonprofit corporation that promotes sustainable homes,
workplaces and communities through education, research,
advocacy and technical assistance. This URL contains a
PDF version of the referenced document.
Duct Sealing
www.southface.org/home/sfpubs/techshts
/2duct_q&a.pdf
Located in Atlanta, Southface Energy Institute is a 501(c)(3)
nonprofit corporation that promotes sustainable homes,
workplaces and communities through education, research,
advocacy and technical assistance. This URL contains a
PDF version of the referenced document.
www.southface.org/home/sfpubs/techshts/checklist.pdf
Located in Atlanta, Southface Energy Institute is a 501(c)(3)
nonprofit corporation that promotes sustainable homes,
workplaces and communities through education, research,
advocacy and technical assistance. This URL contains a
PDF version of the referenced document.
www.ibacos.com/ghome/Oct03/bpflexduct.html
This document by IBACOS provides guidelines for
connecting flex duct to duct board.
Terms and definitions for energy efficiency economics is
offered in two organized lists: Energy-Efficiency, Code and
Rating Terminology & Economic, Financial & Real Estate
Terminology. Both lists are useful for Energy Raters to
effectively perform their function as energy auditors.
www.eeba.org
The Energy and Environmental Building Association (EEBA)
promotes the awareness, education and development of
energy efficient, environmentally responsible buildings and
communities. The EEBA Web site includes a bookstore
where the referenced document may be purchased.
APPENDIX III
www.energycodes.gov/support/code-notes.stm
DOE’s building codes program provides draft Code Notes
to help code officials
www.eeba.org
The Energy and Environmental Building Association (EEBA)
promotes the awareness, education and development of
energy efficient, environmentally responsible buildings and
communities. The EEBA Web site includes a bookstore
where the referenced document may be purchased.
www.fsec.ucf.edu
Florida Solar Energy Center (FSEC), A Research Institute
of the University of Central Florida, conducts research
and develops energy technologies that enhance Florida’s
and the nation’s economy and environment. FSEC also
educates the public, students and practitioners on the
results of the research.
www.e-star.com
E-Star Energy Ratings allow homeowners and builders
to create energy-efficient homes that are economical,
comfortable, and better for the environment.
APPENDIX I
No Web sites
Building America Best Practices Series: Volume 4 – Builders and Buyers Handbook for
Improving New Home Efficiency, Comfort, and Durability in the Mixed Humid Climate
Version 1, 9/2005 • APPENDIX V-10
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Building America Best Practices Series: Volume 4. Builders and
Buyers Handbook for Improving New Home Efficiency, Comfort, and
Durability in the Mixed-Humid Climate
DE-AC36-99-GO10337
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Michael C. Baechler, Z. Todd Taylor, Rosemarie Bartlett, Theresa
Gilbride, Marye Hefty, Heidi Steward, Pat M. Love, and Jennifer A.
Palmer
NREL/TP-550-38448
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Golden, CO 80401-3393
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14. ABSTRACT (Maximum 200 Words)
This best practices guide is part of a series produced by Building America. The guide book is a resource to help
builders large and small build high-quality, energy-efficient homes that achieve 30% energy savings in space
conditioning and water heating in the mixed-humid climate region. The savings are in comparison with the 1993
Model Energy Code. The guide contains chapters for every member of the builder’s team—from the manager to the
site planner to the designers, site supervisors, the trades, and marketers. There is also a chapter for homeowners on
how to use the book to provide help in selecting a new home or builder.
15. SUBJECT TERMS
Building America; mixed-humid climate region; U.S. Department of Energy; energy-efficient houses; home comfort;
house durability
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Standard Form 298 (Rev. 8/98)
Prescribed by ANSI Std. Z39.18
F1146-E(12/2004)
A Strong Energy Portfolio
for a Strong America
Energy efficiency and clean, renewable
energy will mean a stronger economy,
a cleaner environment, and greater
energy independence for America.
Working with a wide array of state,
community, industry, and university
partners, the U.S. Department of
Energy’s Office of Energy Efficiency
and Renewable Energy invests in a
diverse portfolio of energy technologies.
Research and Development
of Buildings
Our nation’s buildings consume more
energy than any other sector of the
U.S. economy, including transportation
and industry. Fortunately, the opportunities to reduce building energy use—
and the associated environmental
impacts—are significant.
DOE’s Building Technologies Program
works to improve the energy efficiency
of our nation’s buildings through innovative new technologies and better
building practices. The program
focuses on two key areas:
• Emerging Technologies
Research and development of the
next generation of energy-efficient
components, materials, and
equipment
• Technology Integration
Integration of new technologies
with innovative building methods
to optimize building performance
and savings
For more information contact:
EERE Information Center
1-877-EERE-INF (1-877-337-3463)
www.eere.energy.gov
Visit our Web sites at:
www.buildingamerica.gov
www.pathnet.org
www.energystar.gov
Building America Program
George S. James • New Construction • 202-586-9472 • fax: 202-586-8134 • e-mail: [email protected]
Terry Logee • Existing Homes • 202-586-1689 • fax: 202-586-4617 • e-mail: [email protected]
Lew Pratsch • Integrated Onsite Power • 202-586-1512 • fax: 202-586-8185 • e-mail: [email protected]
Building America Program • Office of Building Technologies, EE-2J • U.S. Department of Energy • 1000 Independence Avenue, S.W. •
Washington, D.C. 20585-0121 • www.buildingamerica.gov
Building Industry Research Alliance (BIRA)
Robert Hammon • ConSol • 7407 Tam O’Shanter Drive #200 • Stockton, CA 95210-3370 • 209-473-5000 • fax: 209-474-0817 •
e-mail: [email protected] • www.bira.ws
Building Science Consortium (BSC)
Betsy Pettit • Building Science Consortium (BSC) • 70 Main Street • Westford, MA 01886 • 978-589-5100 • fax: 978-589-5103 •
e-mail: [email protected] • www.buildingscience.com
Consortium for Advanced Residential Buildings (CARB)
Steven Winter • Steven Winter Associates, Inc. • 50 Washington Street • Norwalk, CT 06854 • 203-857-0200 • fax: 203-852-0741 •
e-mail: [email protected] • www.carb-swa.com
Davis Energy Group
David Springer • Davis Energy Group • 123 C Street • Davis, CA 95616 • 530-753-1100 • fax: 530-753-4125 •
e-mail: [email protected][email protected] • www.davisenergy.com/index.html
IBACOS Consortium
Brad Oberg • IBACOS Consortium • 2214 Liberty Avenue • Pittsburgh, PA 15222 • 412-765-3664 • fax: 412-765-3738 •
e-mail: [email protected] • www.ibacos.com
Industrialized Housing Partnership (IHP)
Subrato Chandra • Florida Solar Energy Center • 1679 Clearlake Road • Cocoa, FL 32922 • 321-638-1412 • fax: 321-638-1439 •
e-mail: [email protected] • www.baihp.org
National Association of Home Builders (NAHB) Research Center
Tom Kenney • National Association of Home Builders (NAHB) Research Center • 400 Prince George’s Boulevard •
Upper Marlboro, MD 20774 • 301-430-6246 • fax: 301-430-6180 • toll-free: 800-638-8556 • www.nahbrc.org/
National Renewable Energy Laboratory
Ren Anderson • 1617 Cole Boulevard, MS-2722 • Golden, CO 80401 • 303-384-7433 • fax: 303-384-7540 •
e-mail: [email protected] • www.nrel.gov
U.S. Department of Energy
Energy Efficiency
and Renewable Energy
An electronic copy of this publication is
available on the Building America Web
site at www.buildingamerica.gov
Tim Merrigan • 1617 Cole Boulevard, MS-2722 • Golden, CO 80401 • 303-384-7349 • fax: 303-384-7540 •
e-mail: [email protected] • www.nrel.gov
Oak Ridge National Laboratory
Pat M. Love • P.O. Box 2008 • One Bethel Valley Road • Oak Ridge, TN 37831 • 865-574-4346 • fax: 865-574-9331 •
e-mail: [email protected] • www.ornl.gov
Produced for the U.S. Department of Energy (DOE) by the National Renewable Energy Laboratory, a DOE national laboratory.
September 2005 • NREL/TP-550-38448
Printed with a renewable-source ink on paper containing at least 50% wastepaper, including 20% postconsumer waste.
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