CBECC-Res USER MANUAL FOR CALIFORNIA BUILDING

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CBECC-Res USER MANUAL FOR CALIFORNIA BUILDING | Manualzz

California Energy Commission

STAFF REPORT

CBECC-Res USER MANUAL

FOR CALIFORNIA BUILDING ENERGY

CODE COMPLIANCE (CBECC-RES)

PUBLIC DOMAIN SOFTWARE

Computer Performance Compliance with the 2013 California Building Energy Efficiency Standards

MAY 2014

CALIFORNIA

ENERGY

COMMISSION

Dee Anne Ross

Primary Author

Martha Brook

Project Manager

Eurlyne Geisler

Office Manager

Building Standards Office

David Ashuckian

Deputy Director

Efficiency Division

Robert P. Oglesby

Executive Director

ACKNOWLEDGMENTS

The Building Energy Efficiency Standards (standards) were first adopted and put into effect in 1978 and have been updated periodically in the intervening years. The standards are a unique California asset and have benefitted from the conscientious involvement and enduring commitment to the public good of many persons and organizations along the way. The 2013 standards development and adoption process continued that long-standing practice of maintaining the standards with technical rigor, challenging but achievable design and construction practices, public engagement and full consideration of the views of stakeholders.

The revisions in the 2013 standards were conceptualized, evaluated and justified through the excellent work of Energy Commission staff and consultants. This document was created with the assistance of Energy Commission staff including Martha Brook, PE, Doug Herr, Jeff Miller, PE,

Dee Anne Ross, and Danny Tam.

Other key technical staff contributors included Payam Bozorgchami, Tav Commins, Todd Ferris,

Gary Flamm, Rob Hudler, Alan Marshall, Nelson Peña, Bill Pennington, Maziar Shirakh, PE, and the

Energy Commission’s Web Team. Dave Ashuckian, Deputy Director of the Efficiency and Renewable

Energy Division, provided policy guidance to the Staff. Pippin Brehler and Michael Levy provided legal counsel to the staff.

Special thanks to our key consultants, including Scott Criswell, Bruce Wilcox, Ken Nittler, Robert

Scott, and Jennifer Roberts. i

ABSTRACT

The 2013 Building Energy Efficiency Standards for Low-Rise Residential Buildings allow compliance by either a prescriptive or performance method. Performance compliance uses computer modeling software to trade off efficiency measures. For example, to allow more windows, the designer will specify more efficient windows, or to allow more west-facing windows they will install a more efficient cooling system. Computer performance compliance is typically the most popular compliance method because of the flexibility it provides in the building design.

The Energy Commission is required by the Warren-Alquist Act to provide a public domain compliance program. The California Building Energy Code Compliance (CBECC-Res) software is the public domain software that will be certified by the Energy Commission in conformance with the

Residential Alternative Calculation Methods (ACM) Approval Manual, which contains the process for approving compliance software. CBECC-Res must also comply with the modeling requirements of the Residential Alternative Calculation Methods (ACM) Reference Manual, which establishes the rules for the how the proposed design (energy use) is defined, how the standard design (energy budget) is established, and what is reported on the Certificate of Compliance (CF1R).

CBECC-Res is the 2013 Compliance Manager, which is the simulation and compliance rule implementation software. CBECC-Res is used to model all components that affect the energy performance of the building, as required for complying with the 2013 Building Energy Efficiency

Standards. A Certificate of Compliance (CF1R), signed by a documentation author and a responsible party (either the building owner or designer), reports all of the energy features for verification by the building enforcement agency.

Keywords: ACM, Alternative Calculation Method, Building Energy Efficiency Standards, California

Energy Commission, California Building Energy Code Compliance, CBECC, CBECC-Res, Certificate of Compliance, CF1R, compliance manager, computer compliance, energy budget, energy standards, energy use, performance compliance, public domain, Title 24, Title 24 compliance software ii

TABLE OF CONTENTS

Chapter 1.

Overview ...................................................................................................................................... 1-1

1.1

Approval for Compliance ................................................................................................................... 1-1

1.2

1.3

1.4

1.5

Background ....................................................................................................................................... 1-1

Program Updates .............................................................................................................................. 1-2

Software Capabilities ........................................................................................................................ 1-2

Fixed and Restricted Inputs .............................................................................................................. 1-2

1.6

1.7

1.8

Preparing Basic Input ........................................................................................................................ 1-2

Documentation .................................................................................................................................. 1-3

Registered CF1R .............................................................................................................................. 1-3

1.9

Special Features and Modeling Assumptions ................................................................................... 1-3

1.10

Field Verification ................................................................................................................................ 1-3

1.11

Checklist for Compliance Submittal .................................................................................................. 1-4

1.12

Related Publications ......................................................................................................................... 1-4

1.13

Terminology ...................................................................................................................................... 1-5

1.13.1

1.13.2

1.13.3

1.13.4

Compliance Manager ............................................................................................................... 1-5

Report Manager........................................................................................................................ 1-5

Proposed Design ...................................................................................................................... 1-5

Standard Design ....................................................................................................................... 1-5

1.13.5

1.13.6

Mandatory Requirements ......................................................................................................... 1-6

Climate Zone ............................................................................................................................ 1-6

1.13.7

HERS Verification ..................................................................................................................... 1-6

Chapter 2.

Getting Started ............................................................................................................................ 2-1

2.1

2.2

2.2.1

2.2.2

Installing CBECC-Res ....................................................................................................................... 2-1

Menu Bar ........................................................................................................................................... 2-1

File ............................................................................................................................................ 2-2

Edit ........................................................................................................................................... 2-2

iii

2.2.3

2.2.4

Ruleset ..................................................................................................................................... 2-2

View .......................................................................................................................................... 2-2

2.3

2.4

2.2.5

2.2.6

Tools ......................................................................................................................................... 2-2

Help .......................................................................................................................................... 2-3

Tool Bar ............................................................................................................................................. 2-3

Main Screen ...................................................................................................................................... 2-4

2.6

2.7

2.8

2.9

2.5

2.5.1

Right-Click Menu Options ................................................................................................................. 2-4

Analysis Types ......................................................................................................................... 2-5

2.5.2

2.5.3

Building Tree Controls (Parent/Child Relationships) ................................................................ 2-5

Rapid Editing ............................................................................................................................ 2-6

Input Dialog Windows ....................................................................................................................... 2-6

Background Colors ............................................................................................................................ 2-6

Status Bar ......................................................................................................................................... 2-6

Defining New Components ............................................................................................................... 2-7

2.10

Managing Project Files...................................................................................................................... 2-8

2.11

Error Messages ................................................................................................................................. 2-8

Chapter 3.

Tutorial ......................................................................................................................................... 3-1

3.1

Sample Files ..................................................................................................................................... 3-1

3.2

Simple House Example ..................................................................................................................... 3-1

Chapter 4.

Project .......................................................................................................................................... 4-1

4.1

4.2

Tool Tips/Automated Features .......................................................................................................... 4-1

Project Information ............................................................................................................................ 4-2

4.3

4.4

4.4.1

4.4.2

Analysis ............................................................................................................................................. 4-2

Building ............................................................................................................................................. 4-4

Building Information .................................................................................................................. 4-5

Dwelling Unit Details, Multi Family ........................................................................................... 4-7

4.5

4.6

Lighting/Appliances ........................................................................................................................... 4-8

IAQ Ventilation .................................................................................................................................. 4-8

iv

4.7

Cooling Ventilation ............................................................................................................................ 4-9

Chapter 5.

Zones ........................................................................................................................................... 5-1

5.1

5.2

5.2.1

5.2.2

Multiple Conditioned Zones .............................................................................................................. 5-1

Attic ................................................................................................................................................... 5-1

Attic Zone Data ......................................................................................................................... 5-1

Cool Roof .................................................................................................................................. 5-4

5.2.3

5.3

Low Slope Aggregate Roof ...................................................................................................... 5-4

Crawl Space ...................................................................................................................................... 5-4

5.3.1

5.4

Crawl Space Zone Data ........................................................................................................... 5-5

Conditioned Zone .............................................................................................................................. 5-5

5.4.1

5.5

Conditioned Zone Data ............................................................................................................ 5-6

Garage .............................................................................................................................................. 5-7

5.5.2

Garage Zone Data .................................................................................................................... 5-8

Chapter 6.

Construction Assemblies .......................................................................................................... 6-1

6.5.1

6.5.2

6.5.3

6.5.4

6.5.5

6.5.6

6.1

6.2

6.3

6.4

Cavity R-Value .................................................................................................................................. 6-1

Assembly Types ................................................................................................................................ 6-1

Mandatory Envelope Requirements .................................................................................................. 6-2

Spray Foam Insulation (SPF) ............................................................................................................ 6-2

6.4.1

6.4.2

Medium Density Closed-Cell SPF Insulation ........................................................................... 6-3

Low Density Open-Cell SPF Insulation .................................................................................... 6-3

6.4.3

6.5

Advanced Wall Framing ........................................................................................................... 6-3

Attic Roof Terminology ...................................................................................................................... 6-3

Attic ........................................................................................................................................... 6-3

Cathedral Ceiling ...................................................................................................................... 6-3

Ceiling Below Attic .................................................................................................................... 6-4

Knee Wall ................................................................................................................................. 6-4

Low Slope Roof ........................................................................................................................ 6-4

Radiant Barrier ......................................................................................................................... 6-4

v

6.5.7

6.5.8

Roof .......................................................................................................................................... 6-4

Steep Slope Roof ..................................................................................................................... 6-5

6.6

6.6.1

Attic Construction .............................................................................................................................. 6-5

Attic Construction Data ............................................................................................................. 6-5

6.6.2

6.7

Construction Layers ................................................................................................................. 6-6

Ceiling Below Attic and Interior Ceilings ........................................................................................... 6-7

6.7.1

6.7.2

6.7.3

6.7.4

Ceiling Below Attic Construction Data ...................................................................................... 6-7

Construction Layers ................................................................................................................. 6-8

Cathedral Ceiling Construction Data ...................................................................................... 6-10

Construction Layers ............................................................................................................... 6-11

6.7.5

6.8

Cathedral Ceiling Data ........................................................................................................... 6-11

Walls................................................................................................................................................ 6-12

6.8.1

6.8.2

Interior and Exterior Wall Construction Data .......................................................................... 6-13

Framed Wall Construction Layers (inside to outside) ............................................................ 6-13

6.8.3

6.8.4

6.8.5

6.8.6

Mass or Other Unframed Walls .............................................................................................. 6-14

Structurally Insulated Panels (SIPs) ....................................................................................... 6-15

Demising and Interior Walls ................................................................................................... 6-15

Garage Exterior Walls ............................................................................................................ 6-16

6.9

6.9.1

Floors .............................................................................................................................................. 6-16

Raised Floor Construction Data ............................................................................................. 6-17

6.9.2

6.9.3

Raised Floor Construction Layers (top to bottom) ................................................................. 6-18

Floor Over Garage ................................................................................................................. 6-18

6.9.4

Window Types ........................................................................................................................ 6-19

Chapter 7.

Building Envelope ...................................................................................................................... 7-1

7.1

7.2

Orientation ......................................................................................................................................... 7-1

Opaque Surfaces .............................................................................................................................. 7-2

7.2.1

7.2.2

Ceiling below attic .................................................................................................................... 7-2

Cathedral Ceiling ...................................................................................................................... 7-3

vi

7.2.3

7.2.4

Knee Walls ............................................................................................................................... 7-4

Party Walls in Multi-Family ....................................................................................................... 7-4

7.2.5

7.2.6

Walls ......................................................................................................................................... 7-5

Opaque Doors .......................................................................................................................... 7-6

7.2.7

7.3

Garage Door ............................................................................................................................. 7-7

Windows ............................................................................................................................................ 7-7

7.3.1

7.3.2

7.3.3

7.3.4

Windows Data .......................................................................................................................... 7-7

Window Overhang .................................................................................................................... 7-9

Window Fins ........................................................................................................................... 7-10

Glass Doors ............................................................................................................................ 7-11

7.4

7.5

7.5.1

7.5.2

Skylights .......................................................................................................................................... 7-12

Raised Floor .................................................................................................................................... 7-13

Floor over Crawl Space .......................................................................................................... 7-13

Floor Over Garage ................................................................................................................. 7-14

7.5.3

7.6

Floor Over Exterior ................................................................................................................. 7-15

Slab Floor ........................................................................................................................................ 7-17

7.7

Exterior Garage Surfaces................................................................................................................ 7-18

Chapter 8.

Mechanical Systems ................................................................................................................... 8-1

8.1

8.1.2

HVAC System Data ........................................................................................................................... 8-1

Zonal Control ............................................................................................................................ 8-3

8.1.3

8.2

Multiple HVAC Systems ........................................................................................................... 8-4

Heating Systems ............................................................................................................................... 8-4

8.2.1

8.2.2

8.2.3

8.2.4

8.2.5

8.2.6

Heating System Data (other than heat pump) .......................................................................... 8-5

Heat Pumps (Air Source) ......................................................................................................... 8-6

Air to Water Source Heat Pump ............................................................................................... 8-9

Ground Source Heat Pump .................................................................................................... 8-10

Hydronic Heating .................................................................................................................... 8-11

Hydronic Distribution Systems and Terminals ....................................................................... 8-11

vii

8.2.7

8.2.8

Wood Heating ......................................................................................................................... 8-12

Electric Heat ........................................................................................................................... 8-12

8.2.9

8.3

Non-central Heating ............................................................................................................... 8-12

Cooling Systems ............................................................................................................................. 8-12

8.3.1

8.3.2

Cooling System Data .............................................................................................................. 8-13

No Cooling .............................................................................................................................. 8-15

8.3.3

8.3.4

Non-central Cooling ................................................................................................................ 8-15

Evaporative Cooling ............................................................................................................... 8-16

8.4

8.4.2

Distribution System Data................................................................................................................. 8-16

Low Leakage Air Handlers ..................................................................................................... 8-20

8.5

8.6

8.4.3

8.4.4

Verified Low Leakage Ducts in Conditioned Space ............................................................... 8-20

Buried Ducts ........................................................................................................................... 8-20

HVAC Fan System .......................................................................................................................... 8-21

Indoor Air Quality (IAQ) Fan Data ................................................................................................... 8-22

8.7

Cooling Ventilation Fans ................................................................................................................. 8-23

Chapter 9.

Domestic Hot Water (DHW) ........................................................................................................ 9-1

9.1

9.2

Efficiency Information ........................................................................................................................ 9-1

Water Heater Types .......................................................................................................................... 9-1

9.3

9.3.1

Distribution Types ............................................................................................................................. 9-2

Single Family Distribution Type ................................................................................................ 9-2

9.3.2

9.4

Multi-Family Distribution Type .................................................................................................. 9-3

Water Heating System Data ............................................................................................................. 9-4

9.5

9.6

Solar Water Heating Data ................................................................................................................. 9-5

Water Heater Data ............................................................................................................................ 9-6

Chapter 10.

Additions and Alterations .................................................................................................... 10-1

10.1

Addition Alone ................................................................................................................................. 10-1

10.2

10.2.1

Setting the Standard Design ........................................................................................................... 10-1

Third Party Verification ........................................................................................................... 10-1

viii

10.2.2

Efficiency Threshold ............................................................................................................... 10-2

10.3

Existing Building .............................................................................................................................. 10-2

10.4

Addition ........................................................................................................................................... 10-3

10.5

Addition/Alteration ........................................................................................................................... 10-4

10.5.1

10.5.2

Radiant Barrier ....................................................................................................................... 10-5

HVAC ...................................................................................................................................... 10-6

10.5.3

10.5.4

10.5.5

Water heating ......................................................................................................................... 10-7

Mechanical Ventilation ........................................................................................................... 10-8

Ventilation Cooling/Whole House Fan ................................................................................... 10-8

Appendix A: CBECC Approval

Appendix B: Certificate of Compliance ix

FIGURES

Figure 2-1: Setup ................................................................................................................................................ 2-1

Figure 2-2: Menu and Tool Bar .......................................................................................................................... 2-1

Figure 2-3: Main Screen ..................................................................................................................................... 2-4

Figure 3-1: Simple House Example .................................................................................................................... 3-2

Figure 3-2: Output for Simple House in Climate Zone 12 .................................................................................. 3-6

Figure 3-3: Updated Output for Simple House ................................................................................................... 3-7

Figure 4-1: Project Information ........................................................................................................................... 4-2

Figure 4-2 Analysis Information .......................................................................................................................... 4-2

Figure 4-3: Building Information ......................................................................................................................... 4-4

Figure 4-4: Multi-Family Dwelling Unit Details ................................................................................................... 4-7

Figure 4-5: Cooling Ventilation ........................................................................................................................... 4-9

Figure 5-1: Attic Model Components .................................................................................................................. 5-2

Figure 5-2: Attic Zone Data ................................................................................................................................ 5-2

Figure 5-3: Crawl Space Zone ........................................................................................................................... 5-5

Figure 5-4: Conditioned Zone Data .................................................................................................................... 5-6

Figure 5-5: Garage Zone Data ........................................................................................................................... 5-8

Figure 6-1: Attic Construction Data .................................................................................................................... 6-5

Figure 6-2: Ceiling Below Attic Data ................................................................................................................... 6-7

Figure 6-3: Ceiling Below Attic Assembly........................................................................................................... 6-8

Figure 6-4: Section at Attic Edge with Standard Truss ...................................................................................... 6-9

Figure 6-5: Section at Attic Edge with a Raised Heel Truss .............................................................................. 6-9

Figure 6-6: Cathedral Ceiling ........................................................................................................................... 6-10

Figure 6-7: Cathedral Ceiling Data ................................................................................................................... 6-12

Figure 6-8: Wood-Framed Wall Construction Data .......................................................................................... 6-13

Figure 6-9: Interior Walls .................................................................................................................................. 6-16

Figure 6-10: Uninsulated Exterior Wall ............................................................................................................. 6-16

x

Figure 6-11: Floor over crawl space ................................................................................................................. 6-17

Figure 6-12: Floor over exterior ........................................................................................................................ 6-17

Figure 6-13: Interior Floor ................................................................................................................................. 6-19

Figure 6-14: Window Type ............................................................................................................................... 6-19

Figure 7-1: Conditioned Zone ............................................................................................................................. 7-1

Figure 7-2: Plan Orientation ............................................................................................................................... 7-2

Figure 7-3: Cathedral Ceiling ............................................................................................................................. 7-3

Figure 7-4: Party Wall ......................................................................................................................................... 7-4

Figure 7-5: Exterior Wall ..................................................................................................................................... 7-5

Figure 7-6: Surface Tilt ....................................................................................................................................... 7-6

Figure 7-7: Opaque Door ................................................................................................................................... 7-6

Figure 7-8: Window Data .................................................................................................................................... 7-8

Figure 7-9: Overhang ....................................................................................................................................... 7-10

Figure 7-10: Window Fin .................................................................................................................................. 7-11

Figure 7-11: Skylight ......................................................................................................................................... 7-12

Figure 7-12: Raised Floor ................................................................................................................................. 7-13

Figure 7-13: Garage or Interior Floor ............................................................................................................... 7-14

Figure 7-14: Multi-Family Interior Floor ............................................................................................................ 7-14

Figure 7-15: Zone Elevation Height .................................................................................................................. 7-15

Figure 7-16: Exterior Floor ............................................................................................................................... 7-16

Figure 7-17: Slab Floor Data ............................................................................................................................ 7-17

Figure 7-18: Attached Garage .......................................................................................................................... 7-18

Figure 8-1: Mechanical Tab ................................................................................................................................ 8-1

Figure 8-2: HVAC System Data ......................................................................................................................... 8-2

Figure 8-3: Zonal Control from Section 4.4.1.8 .................................................................................................. 8-3

Figure 8-4: Type from Section 5.4.1 ................................................................................................................... 8-4

Figure 8-5: Heating System Data ....................................................................................................................... 8-6

Figure 8-6: Heat Pump Data .............................................................................................................................. 8-9

xi

Figure 8-7: Air to Water Source Heat Pump..................................................................................................... 8-10

Figure 8-8: Hydronic Heating Data ................................................................................................................... 8-11

Figure 8-9: Cooling System Data ..................................................................................................................... 8-14

Figure 8-10: Distribution System Data ............................................................................................................. 8-17

Figure 8-11: Duct Leakage ............................................................................................................................... 8-17

Figure 8-12: Buried Ducts ................................................................................................................................ 8-21

Figure 8-13: HVAC Fan .................................................................................................................................... 8-22

Figure 8-14: IAQ Fan Data ............................................................................................................................... 8-22

Figure 8-15: Cooling Ventilation ....................................................................................................................... 8-24

Figure 9-1: Single Family Distribution Systems ................................................................................................. 9-2

Figure 9-2: Multi-Family Distribution Systems .................................................................................................... 9-4

Figure 9-3: Recirculation Loops ......................................................................................................................... 9-5

Figure 9-4: Solar Water Heating Data, Annual ................................................................................................... 9-6

Figure 9-5: Solar Water Heating Data, Monthly ................................................................................................. 9-6

Figure 9-6: Water Heater Data Small Storage ................................................................................................... 9-7

Figure 9-7: Large Storage Water Heater Data ................................................................................................... 9-7

Figure 10-1: Run Scope ................................................................................................................................... 10-1

Figure 10-2: Existing Surface ........................................................................................................................... 10-3

Figure 10-3: Addition HVAC and DHW ............................................................................................................ 10-3

Figure 10-4: Altered with Verified Existing Conditions ..................................................................................... 10-4

Figure 10-5: Altered Without Verified Existing Conditions ............................................................................... 10-5

Figure 10-6: Altered HVAC and DHW .............................................................................................................. 10-6

Figure 10-7: Existing System ........................................................................................................................... 10-7

Figure 10-8: Duct System ................................................................................................................................. 10-7

xii

TABLES

Table 2-1: Input Classification Explanations ....................................................................................................... 2-7

Table 2-2: Data Source Explanations ................................................................................................................. 2-7

Table 4-1: PV Credit Calculation Factors ........................................................................................................... 4-4

Table 4-2: Ventilation Cooling Fans ................................................................................................................... 4-9

Table 5-1: Solar Reflectance and Emittance for Aggregate Materials ............................................................... 5-4

Table 6-1: Compressed Insulation R-values ...................................................................................................... 6-1

Table 6-2: Required Thickness Spray Foam Insulation ..................................................................................... 6-2

Table 8-1: Heating Equipment ............................................................................................................................ 8-5

Table 8-2: Heat Pump Equipment ...................................................................................................................... 8-8

Table 8-3: Cooling Equipment .......................................................................................................................... 8-13

Table 8-4: Air Conditioning Measures Requiring HERS Verification ................................................................ 8-15

Table 8-5: Distribution Type ............................................................................................................................. 8-18

Table 8-6: Summary of Verified Air Distribution Systems ................................................................................ 8-19

Table 8-7: Buried Duct Effective R-values ....................................................................................................... 8-21

Table 9-1: Water Heater Distribution System Multipliers ................................................................................... 9-3

Table 9-2: Default Recirculating Pump Motor Efficiency .................................................................................... 9-5

xiii

CBECC User Manual

Overview

Chapter 1. Overview

1.1 Approval for Compliance

California Building Energy Code Compliance (CBECC-Res 2013) is an open-source software program developed by the California Energy Commission for demonstrating compliance with the low-rise residential 2013 Building Energy Efficiency Standards (“standards”). The standards become effective for new construction on July 1, 2014.

CBECC-Res was originally approved on September 11, 2013 (see Appendix A for the most recent resolution from the Energy Commission). The low-rise residential standards apply to single family dwellings (R-3 occupancy group) and to multi-family buildings (R-1 or R-2) with 3 stories or less.

Hotels, motels, and multi-family buildings with 4 or more stories are outside the scope of the lowrise standards.

The 2013 compliance manager is the simulation and compliance rule implementation software specified by the Energy Commission. The compliance manager, called CBECC-Res, models all features that affect the energy performance of the building . Mandatory requirements, as specified in

Sections 110.0 through 110.10 and 150.0 of the standards, are not always modeled. An exception, for example, is insulation values. Section 150.0 includes mandatory minimum insulation levels for framed walls, floors and ceilings. It is the responsibility of the program’s user to be aware of the requirements of the Building Energy Efficiency Standards .

This manual is a guide to the program’s use. It provides a description of software inputs and a guide to using the software. Knowledge of the standards is a pre-requisite. As the documentation author, you are responsible for the content of the compliance documents produced by CBECC-Res, which are submitted to the enforcement agency as proof of compliance with the standards.

1.2 Background

The standards allow compliance using either a prescriptive or performance method. The prescriptive

method is found in the Residential Compliance Manual (see Section 1.12, Related Publications for

information on obtaining this document). Performance compliance uses building modeling software to demonstrate compliance with the standards. CBECC-Res is the public domain compliance manager, meaning it is the simulation and compliance rule implementation software specified by the

Energy Commission.

The document Residential Alternative Calculation Methods (ACM) Reference Manual (see Section 1.12

Related Publications) explains how the proposed and standard designs are determined. If you have

questions about how the software models a building feature refer to this Reference Manual.

1-1

CBECC User Manual

Overview

1.3 Program Updates

For software updates and valid version numbers check link to the the project website , accessible from www.energy.ca.gov/title24/2013standards/2013_computer_prog_list.html

.

NOTE: Be sure to check for updates regularly and/or get notifications from the Energy Commission because submittals with outdated software will be rejected by the building department. Sign up for e-mail notifications at http://www.energy.ca.gov/efficiency/listservers.html.

1.4 Software Capabilities

Chapter 7 of this User Manual describes what features of the opaque envelope may be modeled and how they are modeled. Chapter 8 addresses the same for mechanical systems and Chapter 9 covers water heating systems. Chapter 10 discusses addition and alteration modeling. For a complete discussion of how the standard design is established, see the 2013 Residential ACM Reference Manual.

1.5 Fixed and Restricted Inputs

When the specified analysis type is compliance, fixed and restricted inputs cannot be changed by the user. Since sample files may include assumptions that are not standard in a given climate zone, to determine the standard assumption for a given input, consult either Section 150.1, Package A, of the

Building Energy Efficiency Standards, or the 2013 Residential ACM Reference Manual.

1.6 Preparing Basic Input

The software includes several sample files, and the user manual provides a tutorial as well as a guide through program inputs. Required inputs include:

1. Building address, climate zone, front orientation, and availability of natural gas,

2. Conditioned floor area and average ceiling height,

3. Attic/roof details, roof pitch, roofing material, solar reflectance and emittance,

4. Ceilings below attic and vaulted ceiling R-values,

5. Wall areas, orientation, and construction details,

6. Door areas and orientation,

7. Slab or raised floor area and construction details,

8. Window and skylight areas, orientation, U-factor, Solar Heat Gain Coefficient,

9. Building overhang and side fin shading,

10. Mechanical heating and cooling equipment type and efficiency,

11. Distribution system location and construction details,

12. Method for providing mechanical ventilation, and

13. Domestic water heating system details, including type of water heating equipment, fuel type, efficiency, distribution system details.

1-2

CBECC User Manual

Overview

1.7 Documentation

CBECC creates a CF1R when you check the PDF box under the Analysis tab (accessible by doubleclicking on Project) . The CF1R will have a watermark that the CF1R is not yet registered (see Section

1.8)

if using valid software with the CF1R generated as part of the compliance calculations . During the registration process the documentation author and responsible person fields will be completed.

There fields are not program inputs for these fields .

Another option for generating a CF1R is toAfter an analysis is performed, you can also produce a

CF1R by select ing Generate Draft T-24 Compliance Report from the tools menu. Note: the watermark will display “not useable for compliance” (for a full explanation of the security features that results in the different watermarks, see the frequently asked question s from November 20, 2013 and March

18, 2014 , accessible from Help/Quick Start Guide).

See Appendix B for a sample of the CF1R.

The Energy Commission no longer produces a Mandatory Measures (MF-1R) form. Mandatory measures documentation is found on the installation certificates (CF2R). You can see a list of forms in

Appendix A of the 2013 Residential Manual and you can access/print forms at the Energy

Commission’s web site: http://www.energy.ca.gov/title24/2013standards/.

1.8 Registered CF1R

When compliance requires HERS verification (some of which are mandatory requirements), the compliance documents must be registered with a HERS provider before applying for a building permit

(see Residential Compliance Manual, Section 2.1.1). The primary document, which is produced by

CBECC-Res, is the Certificate of Compliance (CF1R). Additionally, as construction progresses, follow-up documentation (certificates of installation (CF2R) and certificates of verification (CF3R)) are required to confirm that the required measures are installed.

The file needed to upload a project to a HERS provider is created only when you check the box labeled “Full (XML)” on the Analysis tab. When uploading to the HERS provider, the file is found in the projects folder and is entitled: “[filename] - AnalysisResults-BEES.xml” found in a location such as My Documents/CBECC-Res 2013 Projects folder.

1.9 Special Features and Modeling Assumptions

The 2013 Residential ACM Reference Manual identifies the features that are to be shown as a Special

Feature and Modeling Assumption on the CF1R.

1.10 Field Verification

Appendix C of the 2013 Residential ACM Reference Manual identifies the specific measures that require HERS verification or diagnostic testing. The CF1R produced by CBECC-Res identifies if a

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building includes any measures requiring field testing or verification by a HERS rater as part of the compliance results on the first page. Additionally, as part of the component details, any specific

measures requiring testing or verification are identified. See also Section 1.8 and Section 1.13.7.

1.11 Checklist for Compliance Submittal

The forms and documentation needed for a compliance submittal includes an electronic version of the CF1R, registered with a HERS provider.

Supporting documentation that may could also be required is the roofing material rating from the

Cool Roof Rating Council, solar water heating documentation to support a modeled solar fraction,

AHRI certified efficiency of cooling, heating and/or water heating equipment, NFRC certified Ufactor and Solar Heat Gain Coefficient for windows and skylights.

Any supporting documentation requested by the building department to verify modeled features.

1.12 Related Publications

In addition to this manual, users of the software need to have the following documents as a resource during the compliance process:

2013 Building Energy Efficiency Standards (P400-2012-004-CMF, May 2012) contains the official standards adopted by the Energy Commission.

Residential Compliance Manual (P400-2013-001-SD, June 2013) is the interpretive manual for complying with the standards (also contains sample compliance forms).

Reference Appendices for the 2013 Building Energy Efficiency Standards (P400-2012-005-CMF, May

2012) is the source document for climate zones, HERS protocols for measures requiring verification by a HERS rater, as well as eligibility and installation criteria for energy efficiency measures.

Residential Alternative Calculation Methods (ACM) Reference Manual contains the rules that the software follows to establish the standard and proposed designs for a proposed building.

These documents can be obtaineddownloaded from the Energy Commission website

(www.energy.ca.gov/title24) or purchased from:

California Energy Commission

Publications Office

1516 9th Street

Sacramento, CA 95814

(916) 654-5200

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1.13 Terminology

1.13.1 Compliance Manager

The compliance manager is the simulation and compliance rule implementation software specified by the Energy Commission, otherwise known as the public domain compliance software. The compliance manager is named CBECC-Res and it models the features of the building as specified in the standards, Section 150.1(c) and Table 150.1-A (Package A) to establish the energy budget for the building.

1.13.2 Report Manager

The report manager is a separate program used to generate the Certificate of Compliance (CF1R).

This is a web based application, which enables registering the CF1R, which is required any time there are HERS measures in a building. For more on CF1R registration, see Residential Compliance

Manual, Section 2.1.1.

1.13.3 Proposed Design

The user-defined proposed building modeled in CBECC-Res is called the proposed design. The proposed design energy use is compared to the standard design to determine if the building complies with the standards.

The building configuration is defined by the user through entries for floors, walls, roofs and ceilings, windows, and doors. The areas are defined along with performance characteristics such as insulation

R-values, U-factors, SHGC, etc. The entries for all of these building elements must be consistent with the actual building design and configuration.

1.13.4 Standard Design

CBECC-Res creates a version of the proposed building that has the features of Section 150.1(c) and

Table 150.1-A (Package A) in the specified climate zone to establish the allowed energy budget or standard design. The standard design is compared to the proposed design, and if it complies a

Certificate of Compliance (CF1R) can be produced.

For newly constructed buildings, the standard design building is in the same location and has the same floor area, volume, and configuration as the proposed design, except that wall and window areas are distributed equally between the four main compass points, North, East, South and West.

For additions and alterations, the standard design has the same wall and window areas and orientations as the proposed building.

The basis of the standard design is prescriptive Package A (from Section 150.1(c) of the standards,

Table 150.1-A). Package A requirements (not repeated here) vary by climate zone. Reference

Appendices for the 2013 Building Energy Efficiency Standards (Reference Appendices), Joint Appendix JA2,

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Table 2-1, contains the 16 California climate zones and their representative city. The climate zone can be found by city, county and zip code in JA2.1.1.

Detailed information about how the standard design is established can be found in the Reference

Manual (see Section 1.12).

1.13.5 Mandatory Requirements

Mandatory requirements are found in Sections 100.0 through 110.10 and 150.0 of the standards. Any requirement that is mandatory (some are modeled, some are not) cannot be removed from the proposed building. For example, a building in climate zone 10 may be built without a whole house fan as long as it complies without that feature, because the whole house fan is a feature of Package A in Section 150.1. While the standard design building has all of the features of Package A, measures that are more efficient or less efficient can be modeled in the proposed design as long as it meets the mandatory minimum requirements and meets the energy budget.

A partial list of the changes affecting the building envelope is a minimum of R-30 ceiling/roof insulation, R-19 raised floor insulation, and a maximum of 0.58 U-factor for window (see Section

150.0(q) for exceptions). Space conditioning system mandatory requirements include ducts with R-6 insulation that are sealed and have tested duct leakage, air-handler fan efficacy of 0.58 W/CFM or less, and cooling airflow of greater than 350 CFM/ton. These measures require a Home Energy

Rating System (HERS) rater.

1.13.6 Climate Zone

California has 16 climate zones. The climate zone can be found in the Reference Appendices, Joint

Appendix JA2.1.1, by looking up the city, county, or zip code. The climate zone determines the measures that are part of the building’s standard design (see Section 150.1, Table 150.1-A in the standards).

1.13.7 HERS Verification

Some mandatory requirements and other optional compliance features require a Home Energy

Rating Systems (HERS) rater to perform diagnostic testing or verify the installation. HERS raters are trained and certified by one of the HERS Providers . For a list of currently approved providers see www.energy.ca.gov/HERS/providers.html, which currently includes California Certified Energy

Rating and Testing (CalCERTS) and ConSol Home Energy Efficiency Rating Services, Inc. (CHEERS) .

HERS raters are trained and certified by the provider to perform duct leakage testing, quality insulation installation inspections, refrigerant charge testing, and anyverification and testing requirements as specified in the Reference Appendices, Residential Appendices RA1 – RA4.

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Chapter 2. Getting Started

2.1 Installing CBECC-Res

Click on the hyperlink for CBECC-Res or copy the link into your browser’s address box. Follow the prompts and read/accept the license agreement. You can direct the software to a different drive, but do not change the names of the file folders. The software will create a desktop icon.

Figure 2-1: Setup

2.2 Menu Bar

The menu bar at the top of the screen (see Figure 2-1) allows you to access many of the program’s

features.

Figure 2-2: Menu and Tool Bar

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2.2.1 File

The file menu contains the standard functions for file management, opening and saving files, save as

(to rename a file), and exiting the program.

2.2.2 Edit

In addition to the standard cut, copy, and paste commands, the edit menu contains several commands for editing building descriptions. They are:

• Edit component

• Create component

• Delete component

These menus allow you to edit all building components, including components that are not

displayed on the tree control. Use this method to edit components like schedules and performance

curves.

2.2.3 Ruleset

CBECC-Res 2013 is designed to support multiple rulesets that implement the requirements in different codes. When enabled, the ruleset menu will allow switching to a different compliance ruleset. Typically, changing to a different code requires changes to inputs. Users will need to pay special attention to instructions for performing accurate analysis under a different ruleset.

2.2.4 View

The view menu enables you to toggle on and off the display of the tool bar at the top of the screen and the status bar at the bottom of the screen.

2.2.5 Tools

The tools menu contains the following options:

• Check Building Database

• Generate HVAC Equipment Report Records / documentation for installer and HERS Rater

• Generate DHW Equipment Report Records / documentation for installer and HERS Rater

• Generate IAQ Ventilation Report Records / documentation for installer and HERS Rater

• Building Summary Report (input model) / opens a .csv file in Excel

• Building Summary Report (proposed/standard) / opens two .csv files in Excel (one standard and

one proposed)

• Perform Analysis [same as short-cut key] / runs file to determine if it passes or fails compliance

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• Review Analysis Results / displays compliance results, if available

• Generate T-24 Compliance Report / generates a CF1R with a watermark that it is not useable for

compliance (for a “not registered” watermark see Section 1.7)

2.2.6 Help

• Help Topics (not yet enabled)

• Quick Start Guide (opens an overview of the software and frequently asked questions)

• User Manual (opens this document)

• Mandatory Requirements for Assemblies (opens a list of requirements for construction assemblies; for example, a steel framed wall with no rigid insulation does not comply with the minimum requirement of Section 150.0)

• About . . . (to determine the version of CBECC-Res)

2.3 Tool Bar

This section explains the program features accessed by clicking the icons on the tool bar at the top of

the screen (see Figure 2-2).

New File

This button closes the current file (if one is open) and opens a new file.

Open Existing File

This button launches the open dialog box to enable opening an existing file. If another file is open, a prompt to save that file before proceeding will appear.

Save File

This button saves the file under its current name or launches the save as dialog to enable a new file name.

Cut Selected Item

This button is not currently enabled in CBECC-Res 2013.

Copy Selected Item

This button enables you to copy the selected item on the tree control (along with any child components) to the clipboard. If the copy button is not available from within program dialogs use the keyboard equivalent (Ctrl+C) to copy selected text.

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Paste Contents of Clipboard

This button enables pasting components copied from the tree control to the selected location in the tree control (provided that location is compatible with the stored component). The Paste button is not available from within program dialogs, but you can use the keyboard equivalent, Ctrl+V, to paste text from the Windows clipboard to the selected input field.

Print

This button

is inactive in CBECC-Res. Once a CF1R is produced (see Section 1.7), it is printed

via Adobe Acrobat print options.

Perform Analysis

This button enables launching a compliance analysis using the currently loaded building description. You must save the current building description before performing the analysis.

Compliance Reports

This icon launches the CBECC-Res 2013 Report Viewer when there is a report available to view.

About CBECC-Res 2013

View program license and version information. To access the Quick Start Guide, Frequently

Asked Questions or the User Manual, select Help from the file menu.

2.4 Main Screen

The main screen (see Figure 2-3) is used for editing building descriptions. There are two folder tabs

at the top of the main screen—Envelope and Mechanical. These tabs provide different views of the building description and provide access to two different subsets of building description data.

Figure 2-3: Main Screen

2.5 Right-Click Menu Options

CBECC-Res makes extensive use of menus accessible by right-clicking the mouse button. The functions available through these menus depend on whether you are on the main screen or in an input dialog window.

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Main Screen—Right-Click Menu. When clicked over a building component, the following choices are available:

Edit – Opens the input dialog window for the selected component

Rename – Enables renaming the selected component

Delete – Deletes the selected component

Copy – Copies the selected component with all of its associated (“children”) components

Paste – Adds copied components and children to the selected component

Expand/Contract – Expands or contracts the list of children components (shortcut key is to use the + or – signs)

Create – Enables you to create new child components for the selected component

Input Dialog—Right Mouse Menu. When clicked over an input value in the window, the following choices are available:

Item Help – Accesses help information applicable to the selected input field (feature currently not available)

Topic Help – Accesses help information applicable to the selected component (feature currently not available)

Restore Default – Returns the value of the field to its default value (if applicable)

Critical Default Comment – Opens a dialog enabling you to enter a justification for overriding values designated by the standards as critical defaults, i.e., a value that should only be overridden with special justification (feature currently not available)

2.5.1 Analysis Types

Proposed Only: Simulates the proposed building’s energy use using the 2013 compliance rules without establishing the standard design.

Proposed and Standard: In addition to simulating the proposed design, simulates the standard design building (one that complies with the 2013 prescriptive standards) to establish the energy budget for compliance.

Research: Not yet implemented. Simulates the building input by the user but does not apply the

2013 compliance rules.

2.5.2 Building Tree Controls (Parent/Child Relationships)

In order to analyze a building's energy use, it is necessary to track relationships among building components. CBECC-Res displays these relationships using the familiar tree control found in

Windows™ Explorer and many other applications. For example, under the envelope tab, exterior walls are shown as parents to windows. Windows are connected to exterior walls and appear under walls as children to spaces. The tree controls vary in the components they display depending on which folder is selected.

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2.5.3 Rapid Editing

The tree control can be used to move and copy components or groups of components. To move a component, just drag and drop. If an association is not allowed, the program will prevent the move.

To copy a component, select the component, copy, and paste. It is advisable to rename copied components to maintain readability. Whenever parents components are moved, copied, or deleted, child components are included.

Components shown on the tree can be moved using a drag-and-drop technique provided it results in a compatible parent-child relationship. For example, you can drag a window onto a different wall, but not vice versa.

A set of right-click edit commands can be used with the tree control. These are described above in

Section 2.5. Double-clicking on any component on the tree opens its input dialog window.

2.6 Input Dialog Windows

The attributes of each building component can be edited by opening the input dialog window for the component. The dialog can be opened by double-clicking on the component on the tree control, using the edit option on the right mouse menu, or using the edit component option on the edit menu.

(The tree control does not appear until you have created a project description or loaded an existing project file [Ctrl+O]).

2.7 Background Colors

The following background color convention is used in displaying data on the dialogs:

• White background = available for user input

• Gray background = not user editable

2.8 Status Bar

The status bar at the bottom of the screen provides useful information about each input field. There are three panes on the status bar that provide context-sensitive information. This same information is displayed in the tool tips if you allow the mouse to linger over an input field.

1. Input Description Pane – Concise descriptions of the selected input field are displayed at the far left of the status bar.

2. Input Classification Pane – The next pane to the right on the status bar displays a set of labels

that indicates whether an input is required, optional, or unavailable for input (see Table 2-1).

3. Data Source Pane – The pane at the far right of the status bar displays a set of labels that identify the source of the information (if any) contained in the field. This distinguishes

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between information that is dictated by the compliance checking process and the information

entered, for which you are responsible. The data source labels are explained in Table 2-2.

TEXT DISPLAYED

No field selected

Input is compulsory

Input is required

Input is optional

Input is Critical Default

Field is not editable

Navigation input

Table 2-1: Input Classification Explanations

EXPLANATION

No building data field is currently selected.

Data is required; the program cannot perform a compliance analysis without this input.

Data is required if the field is applicable to your project.

If applicable to your project, you may enter a value; a default value is always acceptable.

You may overwrite the data with a more appropriate entry. You must be prepared to provide documentation substantiating the input value.

The data in this field cannot be edited either because it is defined by the compliance ruleset, is not applicable to the selected compliance ruleset, or is an intermediate calculated parameter.

The purpose of the selected field is to enable you to select a component for editing without having to exit the current component and choose the next component from the tree

TEXT DISPLAYED

No field selected

Value from user

Value from simulation

Value undefined

Value from program

Table 2-2: Data Source Explanations

EXPLANATION

No building data field is currently selected.

The data shown is defined by the user either by direct input or through a wizard selection.

The data shown is defined by an energy simulation.

No data is defined for the field.

The data in this field is defined by the program either to implement requirements and procedures specified in the standards or to conform to building energy modeling conventions.

2.9 Defining New Components

From the main program screen or at any point where you would like to create a component under (a child to the parent component):

• Right-click on the component to which you want to add the new component.

• Select Create, then select the type of object you want to add (only applicable component types will appear on the list).

• Accept the defaults or edit the name, parent, and existing component from which to copy, and click OK.

• Edit the input fields with white backgrounds to describe the new component, and click OK.

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2.10 Managing Project Files

By default, project files are stored at C:\Users\<your username>\My Documents\CBECC-Res-2013-

0\Projects, although this depends on where you installed the program.

To retain a project in the most efficient manner, keep the file name with extension “.ribd” (residential input building design). Additionally, the file name with the extension “.log” is useful for troubleshooting. The other project files are recreated when an analysis is performed.

2.11 Error Messages

If a file will not run and you receive no clear error message a file stored in the projects folder contains the entire record of what occurred with the file. Find a file in the Projects folder with the same name as your input file, with the extension “.log,” and open this text file in notepad:

2013-Jun-06 11:51:52 - Opening Project 'jones1.ribd'...

2013-Jun-06 12:03:20 - Project Saved

2013-Jun-06 12:03:23 - Performing Building Database check...

2013-Jun-06 12:03:23 - Building Database check completed, 0 error(s) found.

2013-Jun-06 12:03:23 - Error: Garage 'Garage' has too few child and/or adjacent surfaces (5, minimum is 6) to be simulated. evaluating rule: Rule

130, 37, Line 10660: Check for sufficient Garage:SurfaceCount

2013-Jun-06 12:03:23 - ERROR: Error encountered evaluating rulelist

'ProposedModelSimulationCheck'

2013-Jun-06 12:03:27 - Opening Project 'jones1.ribd'...

2013-Jun-06 12:04:16 - Project Saved

This identifies a problem with the garage model, which does not have enough surfaces modeled.

After adding a slab floor and a ceiling below attic, the file runs.

If you still find no obvious errors, look for a field in your input file that is blank, such as an area or a

U-factor. This type of error does not always produce an error message. If it is necessary to send an email to [email protected], include the *.ribd file with your name and contact information.

Following is a list of potential error messages:

1 : pszCSEEXEPath doesn't exist

2 : pszCSEWeatherPath doesn't exist

3 : pszDHWDLLPath doesn't exist

4 : One or more missing files (CSE, ASHWAT or T24*(DHW/ASM32/TDV/UNZIP/WTHR) DLLs)

5 : pszBEMBasePathFile doesn't exist

6 : pszRulesetPathFile doesn't exist

7 : Error initializing BEMProc (database & rules processor module)

8 : Error initializing compliance ruleset

9 : Invalid project log file name (too long)

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10 : Error writing to project log file

11 : Building model input/project file not found

12 : Error reading/initializing model input/project file

13 : Error evaluating ProposedInput rules

14 : Error retrieving CSE weather file name (from Proj:WeatherFileName)

15 : Energy (CSE) simulation weather file not found

16 : Error retrieving DHW weather file name (from Proj:DHWWthrFileName)

17 : DHW simulation weather file not found

18 : Error retrieving required data: Proj:RunID and/or Proj:RunAbbrev

19 : Analysis processing path too long

20 : Error evaluating ProposedInput rules

21 : Error evaluating PostProposedInput rules

22 : Error evaluating BudgetConversion rules

23 : Error evaluating ProposedModelCodeCheck rules

24 : Unable to create or access analysis processing directory

25 : Unable to open/delete/write simulation output file (.csv or .rep)

26 : Unable to open/delete/write simulation weather file

27 : Error copying simulation weather file to processing directory

28 : Unable to open/delete/write simulation input (.cse) file

29 : Error writing simulation input (.cse) file

30 : CSE simulation not successful - error code returned

31 : DHW simulation not successful

32 : Error encountered loading CSE DLL(s)

33 : Error evaluating ProposedModelCodeCheck rules

34 : Error evaluating ProposedModelSimulationCheck rules

35 : Error evaluating ProposedModelCodeAdditions rules

36 : User aborted analysis via progress dialog 'Cancel' button

37 : Error evaluating ProposedInput rules

38 : Error performing range and/or error checks on building model

39 : Error evaluating CSE_SimulationCleanUp rules

40 : Error generating model report

41 : Error evaluating ProcessResults rules

42 : Error evaluating ProposedCompliance rules

43 : Error(s) encountered reading building model (project) file

44 : Error(s) encountered evaluating rules required analysis to abort

45 : Unable to write compliance report file (.pdf or .xml)

46 : Error(s) encountered generating compliance report file (.pdf or .xml)

47 : Error setting up check of weather file hash

48 : Error evaluating CheckFileHash rules

49 : Weather file hash failed consistency check

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Tutorial

Chapter 3. Tutorial

Note: This tutorial is specific to CBECC-Res 2013 version 2.

3.1 Sample Files

This is a step-by-step tutorial for modeling a simple single-family residence in CBECC-Res 2013 1f.

Although this tutorial will begin with a blank project, it is helpful to note that in the CBECC-Res

“Projects” directory are several sample input files, including:

1. 1StoryExample13.ribd. Based on the Energy Commission’s 2100 ft 2 single floor prototype with slab-on-grade floors, a tile roof, an attached garage, window dimension inputs, overhangs, with the garage modeled as a fin (providing shading to windows).

2. 1StoryExample13Crawl.ribd. Same as above with a crawl space.

3. 2StoryExample13.ribd. Based on the CEC 2700 ft 2 two-story prototype with asphalt shingle roof, this file has window dimension inputs, Compliance 2015, and a Photovoltaic power compliance credit.

4. 2Story2ZoneExample13.ribd. Same as above but zoned 1st and 2nd story each with its own

HVAC system.

5. MFexample13.ribd. An eight-unit two-story multi-family 6960 ft 2 two-story building with each story as a separate zone with four dwelling units in each zone, served by individual water heaters.

Not every input field will be discussed in this tutorial, but every input has a description in the appropriate chapter. Use the Table of Contents or the Index to find specific information. Additional information may also be found in the 2013 Residential Alternative Calculation Method (ACM)

Reference Manual which discusses how the standard design is determined which may provide insight on the compliance results.

TIP: As you are progress through the tutorial, look around each of the screens and fields so you get an idea where changes can be made when you are working on a project.

3.2 Simple House Example

The house pictured in Figure 3-1 has a 30 ft by 20 ft living area, 8-ft ceilings with an attic above, and a

slab-on-grade floor.

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Figure 3-1: Simple House Example

Tutorial

On the south façade (front) is a single 3'-0" x 6'-8" front door. The east (right) has a 3'0” 3'0”window and north (back) facades has two 3'0” 3'0”windows and a 5’0” 6’8” sliding glass door with insulated glazing.

To model this home:

1. Download, install and start the CBECC-Res program. (The program can be downloaded from www.bwilcox.com/BEES/BEES.html ). At the opening (main) screen dialog box, activate the button “Start with a Blank Project” and click <OK>.

2. Right click on the “Press Alt+F…” text line. Choose create project from the drop-down menu, and enter the project name “Simple House” and click <OK>.

3. Next you will pick the climate zone. Select Zone 12 (Sacramento) . You can select any climate zone, however program defaults are based on Package A so your results for this tutorial may be different.

4. You will now be at the Project tab of the building model data. The name “Simple House” is filled in, and becomes the default name for the input file. Enter the address:

1450 20th St

Sacramento, CA

95811

<Select> CZ12 (Sacramento)

5. Rather than clicking OK (which will take you out of the building model data) click the

Analysis tab to enter a run title, which is a field for your own notes or project information such as a compliance variable (e.g., w/ tankless water heater). The information will appear on the CF1R as “Calculation Description.”

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6. Check the box to Generate Report(s),  PDF (note: the Full (XML) box generates the file that will get uploaded to the HERS provider). Keep the run scope as Newly Constructed.

7. Click on Building and enter a description such as “Single Family Residence,” enter the front orientation as “180” (see North arrow in above figure) and number of bedrooms as “2.” For this example, we will assume the building has natural gas and we will not model an attached garage.

8. For now we will leave the Indoor Air Quality and Cool Vent tabs alone. IAQ will model an appropriately sized default exhaust fan. Cool vent (for example, a whole house fan) will be set for you based on the climate zone and the presence of an attic.

9. Click “OK”. Either click on the save button or Select <File>, <Save As> and name the file

Simple House.ribd.

10. Some getting around tips are that the project is called Simple House (so that is the default name for the input file). This name appears at the head of the project tree of the main CBECC-

Res screen. Next we will add child components to the parent component.

To add components, right click on the parent component and choose <create> and pick the type of component you wish to add.

To edit an existing component, either double click, or right click and pick <edit>.

If you need to edit or check a project component (address, climate zone, front orientation,

IAQ ventilation, etc.) double click on the word project and it brings up the initial screen with the project tabs running across the top of the screen.

Items in the project tree Construction Assemblies and Material Layers are not project components, but are a library of assemblies and materials. At this point some of the folders are empty but will be populated by the time the input file is fully created.

11. To continue, right click on the Project title. From the drop-down menu choose <create> then choose <zone>. Enter the zone name “House” and click <OK>.

12. At the next dialog box, the zone type is “Conditioned” and you will enter “600” square feet for the floor area and “8” feet for the average ceiling height. Click <OK>. You have created a child component to the project component, which can now be described more fully.

13. You are at the Zone Data tab of the building model data dialog box, where you will add an

HVAC system to the conditioned zone. a. Click the drop-down menu arrow at the HVAC System box and choose to <Create new

HVAC System>. At the next dialog box accept the default name by clicking <OK>. b. At the HVAC System Type, pick from the drop down menu “Other Heating and Cooling

System” and click <OK>.

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c. This opens the HVAC System Data fields where you will define the system, starting with the Heating Unit. From the drop down box where it has “–none-“ pick <create new heating system>. For now keep the default name Heating System 1 and click <OK>. Pick the equipment type as “CntrlFurnace” and keep the default 78 AFUE and click <OK>. d. Now move to Cooling Unit and follow the same process – picking SplitAirCond and keeping the default efficiencies and refrigerant charge settings (since this sample is in a hot climate, we will keep the verified refrigerant charge, which is a HERS verification test, to avoid an energy penalty in this climate zone. The 11.3 default EER does not require

HERS verification. A value higher than 11.3 does require verification as explained in

Section 8.3.1. Click <OK>.

e. In the Distribution field follow the same procedure—selecting ducts in an unconditioned attic and accepting the default values (a check box sets the default values based on the climate zone). Click <OK>. f. Next create the Fan data. Pick the Single speed furnace fan and click <OK>. Accept the

W/CFM cooling value of “0.58” and click <OK>. g. You are now back at the HVAC System Data tab. Click <OK> to return to the Zone Data.

Although in this exercise we will not further edit the HVAC system, to do so you would access it by clicking on the Mechanical tab at the CBECC-Res main screen where a tree similar to the Envelope tree appears. h. Next click on the drop-down menu arrow at DHW System to begin defining the domestic hot water system components. Pick “create new DHW System” and keep the default system name. Keep the Distribution as “Standard”. Pick from the drop-down menu for

Water Heater(s) 1 “create new Water Heater” and keep the default name. Click <OK> to accept the default characteristics for the water heating system. Click <OK>. We will keep the water heater count as 1. Click <OK> again to accept the building details for floor area, stories, HVAC and DHW systems.

NOTE: In this tutorial we often accept the default names. But you may wish to name your components something more descriptive since you will likely use a previous project to begin a new project and the names will help you identify the characteristics of that component.

14. Next we will add components from the top down, beginning with a 600 square foot ceiling.

Right click on the House zone and choose <create> and then “Ceiling (below attic).” Accept the default name and click <OK>. Then follow the prompts to create a 600 square feet and create a new construction assembly. Set the cavity insulation to R-38 ceiling below attic. Click

<OK> three times. Notice that in addition to the ceiling, the program has created an attic zone with 600 square feet.

15. Next add exterior walls. a. Right click on the House zone again. Choose <create> and then pick <exterior wall>.

Change the Exterior Wall Name to “Front Wall” and click <OK>.

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b. Enter a gross area of 240 square feet of wall area, and for the construction assembly create a new construction. Call it Wall R15/4.” Pick R-15 cavity insulation and an Exterior Finish of R4 Synthetic Stucco (this is the appropriate method for modeling 1-coat stucco). Since the rest of the inputs are correct, click <OK> twice. c. Set the Orientation to front (Note: if you like to model an orientation value rather than

front, left, etc., please read section 7.1 and check the CF1R before printing because

whatever number you enter is added to the front orientation). Leave the wall tilt as 90.

And click <OK>. d. From the House, repeat step b. three more times for a “Left Wall,” “Back Wall” and “Right

Wall” remembering to enter the correct gross wall area (160 for left and right walls, 240 for back wall) and change the orientation to <Left>, <Back> or <Right>. The program will let you copy data from any of the previous Exterior Walls or you can choose “none” at the <Copy Data From> dialog box. Return to the main screen by clicking <OK> after entering the last wall. The walls are child components to the parent House zone.

16. Before creating any windows, first set up the Window Types library in a manner that works for your projects. For example, if you use certain brands of windows, on the row Window

Types, Right Click, and pick <Create>. Give it a name such as Operable.BrandX (0.32, 0.23),

Picture.BrandY (0.31, 0.20), SGD.BrandX (0.28, 0.24) and set the U-factor and SHGC values only (NOTE: even if you wish to accept the default values, type the value in so that the field turns red). This set up allows you to change only the U-factor and SHGC values on a project in the Window Types list without having to go back and edit every window entry (see also

6.9.4). When adding the windows to the given walls, the fields will be blue indicating they are

connected to the Window Type library correctly.

17. Now add the door and windows to the envelope description. The door and windows will be child components of the respective walls in which they are located. Begin with the front door. a. Right click on the Front Wall, choose <create> and then click on <InputDoor>. b. Follow the prompts. The door is 20 square feet. Use the default U-factor (0.50). Return to the main screen.

18. Now move back up to the walls, right click on the Back Wall to <create> a window. Name it

B1 and click <OK>.

19. The next dialog box asks you to choose between window dimensions and overall window

area. Choose window dimension so an overhang can be modeled and click <OK>.

20. You are now at the Window Data tab. Select the Window Type from the library types just added (e.g., Operable) and enter the window height “3” and width “3” and set the multiplier to 2 since we will model identical overhangs for the two windows.

21. Notice that it has picked up the U-factor and SHGC from the window Type. Leave the remaining values as defaults.

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22. To add an overhang, click on the Window Overhang tab at the top of the screen. You will see an illustration of the inputs. Enter a Depth of “2” feet, a Dist Up of “1” foot, and an Extends

Left and Extends Right of “7” feet each. Leave the Flap Height as “0.” Complete the overhang by clicking <OK>.

23. Still on the back wall, create a 5’x6’8” sliding glass door by right-clicking, picking <create> a window named SGD, copy window B1. Pick SGD from the window type library and enter the width as 5 and a height of 6.67. Change the overhang to have a left distance of 3 and a right distance of 22.

24. Finally, right click the Right Wall using the same method to create a window. Tell the program to copy the data from the first window, changing the multiplier to 1. Change the overhang Extends Left and Extends Right values to “10.5” each. All other data remain the same. Click <OK>.

25. Next add a slab floor by moving back up to House. Right click and choose <create> and then pick <Slab on Grade.> Enter an area of 600 square feet, a floor elevation of 0.67 (or the level of the surface of the floor above grade) and a perimeter equal to the length of the four sides exposed to the exterior (100). Note: If there was a garage, the edge no longer includes the length of the edge adjacent to the garage, but only adjacent to the exterior. Keep the surface set to default (80% covered, 20% exposed).

26. The model is now complete. You can edit envelope components by right clicking on them and choosing <edit>. You can add components by right clicking on a parent component and choosing <create> and then clicking on a component type. By choosing the Mechanical tab at the main screen you can similarly edit components of the mechanical systems.

27. To perform an analysis, save your input file using the Save shortcut key, and the Perform

Analysis shortcut key (see page 2-3) (also accessible under the menu for Tools). This will

perform the simulation of the current model, which takes from 3-5 minutes. For comparison,

Figure 3-2 shows the output screen for the model built in this tutorial. You will be able to

view the CF1R since we checked the box to create the PDF. The PDF is generated using a web-based application.

Figure 3-2: Output for Simple House in Climate Zone 12

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28. The project complies. Note that due to the defaulting built into the program it is assumed to have a whole house fan, and a radiant barrier, which may not be desired. As part of this tutorial, we will try trading off some features. If you notice the above compliance margin is in compliance on cooling, so trading away some of the measures that help cooling is feasible.

29. Double click on Attic. This is where the Reflectance and Emittance values for a cool roof product are changed. The roof has a roof rise (pitch) of 5:12. The Construction is where the radiant barrier and above deck (not typical ceiling) insulation and the roofing material is modeled. Click <OK> and move down to the Construction Assemblies (click on the + sign) and double click on Asphalt Shingle Roof. Because Package A in climate zone 12 has a radiant barrier the program included that feature. Uncheck the radiant barrier box. Click <OK> again.

30. Double click on Project and pick the Cool Vent tab (off to the right). If no whole house fan is desired, change the default prescriptive whole house fan to none and click <OK>.

31. Click on the Mechanical tab and double click on the Heating or Cooling System to change the efficiencies. Change the heating system to 80% (not 0.80).

32. Double click on Water Heater 1. Change the Energy Factor to 0.62. Click <OK>. At this point either save the input file with a new name or close the PDF of the CF1R. Save the file and perform the analysis to see if it still complies.

Figure 3-3: Updated Output for Simple House

(results may vary slightly)

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Chapter 4. Project

It is often best to start with an existing input file for a similar project, which will have the structure of the building set up. However, you have the option of starting with a blank project. The sample files included with the software are one-story (slab or crawl space), two-story buildings (one or two zones), and a multi-family building.

Once familiar with the program, you can set up a file template for projects that have a library of assemblies and equipment common to your projects. For example, R-30 cathedral ceilings; R-30 and

R-38 ceilings below attic; tile roofs and asphalt/comp roofs, with or without radiant barriers; typical

2x4 and 2x6 wall construction assemblies; furnaces with 80% and 92% AFUE; and various water heater types and efficiencies typical for your clients.

4.1 Tool Tips/Automated Features

Tool Tips. Some fields have tool tips that are activated by hovering over the field.

File Save. If a file was not saved before you choose to perform an analysis, you are prompted to save it before running. If you select the default save, the file will be saved over the existing file. Thus, if your intention is to create a new version of the file, be sure to pick <cancel> and select <file> and <save as> from the file menu.

Cooling Efficiencies. When minimum cooling equipment efficiencies are specified, these will be updated to the new minimum efficiencies when you switch from 2014 analysis to 2015 (see

Section 4.3.1.4).

Duct R-value. When the “defaults” for ducts are used, if you change the climate zone and the new zone has a different Package A basis, the minimum will be updated (e.g., zone 12 is based on R-6 while zone 11 is based on R-8).

Automated Defaults Based on Climate Zone. When a field such as duct R-value, window Ufactor or SHGC is blue rather than red the value will update based on the default for the selected climate zone. If the field is red and you wish to enable this feature, swipe the cursor across the field, right-click and select “Restore Default.” The field will change from red to blue to indicate that it will change if a climate zone with a different standard design assumption is selected. To prevent unintended changes on window efficiencies, see also

Window Types in Section 7.3.1.4.

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4.2 Project Information

Figure 4-1: Project Information

Project

4.2.1.1 Project Name

The project name is user-defined project information that will appear as the first piece of general information on the CF1R.

4.2.1.2 Building Address

Enter a building address, APN or legal description to identify the location of the proposed building project.

4.2.1.3 City, State

Enter the city or town in which the proposed building is located.

4.2.1.4 Zip Code

The zip code is used to establish the correct climate zone.

4.2.1.5 Climate Zone

Use the zip code and Reference Appendices, JA2.1.1. to determine the correct climate zone.

4.3 Analysis

Figure 4-2 Analysis Information

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4.3.1.1 Run Title

Run title is a field for the software user’s own notes or project information. The information will not appear on the CF1R. It can be used to identify information such as a compliance variable being considered (e.g., “w/ tankless water heater”).

4.3.1.2 Analysis Type

The two types of analysis are proposed and standard design (typical for compliance), and proposed

only.

4.3.1.3 Generate Report(s)

Two options are provided to generate (1) a PDF of the compliance report for review purposes, and

(2) the full (XML) once the project is ready to produce the compliance documentation for upload/submittal. The PDF automatically generated by having the PDF option checked will have a watermark that it has not been registered. Projects that require HERS verification will need to be uploaded to a HERS provider to obtain a registered CF1R before applying for a building permit.

4.3.1.4 Standards Version

Default Compliance 2015.

Compliance 2014 is valid only for permit applications through December 31, 2014 (at which time federal air conditioning efficiency requirements change).

Compliance 2015 is valid any time and required for permit applications made on or after January 1,

2015. At that time new federal cooling equipment standards of 14 SEER and an EER requirement based on equipment capacity of 11.7 EER or higher take effect (for simplification, CBECC assumes

11.7 as the standard minimum EER for all equipment). Compliance 2015 also allows credit for

photovoltaic systems in some climate zones (see 4.3.1.5 below). New standards for water heating also

take effect.

NOTE: When switching between Compliance 2014 and 2015, the minimum cooling efficiency values will change if you used default appliance efficiency levels. The standard design for Compliance 2014 is based on 13 SEER, and is 14 SEER and 11.7 EER for Compliance 2015.

4.3.1.5 PV System Credit

Optional photovoltaic system (PV) credit is available only when Compliance 2015 is selected, and only in climate zones 9-15 for single family and town house projects. Compliance 2015 may be used voluntarily at any time if credit for a PV system is desired. A minimum of 2 kWdc is required for the compliance credit.

The credit assumes updated federal cooling equipment appliance standards and is the smaller of:

PV Generation Rate (kTDV/kWdc) * kWdc

Max PV Cooling Credit * Standard Design Cooling Energy (kTDV)

Where the factors are shown in Table 4-1.

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Table 4-1: PV Credit Calculation Factors

Climate Zone

09

10

11

12

13

14

15

PV Generation Rate

(kTDV/kWdc)

30269

30342

29791

29556

29676

31969

29536

Max PV Cooling Credits ($ of

Standard Design Cooling kTDV/ft2)

13%

15%

18%

17%

17%

16%

19%

The software calculates the solar credit, which is reported as a Special Feature on the CF1R. Systems must meet the eligibility criteria specified in Residential Appendix RA4.6.1.

4.3.1.6 Analysis Report

The default report type is Building Summary (csv).

4.3.1.7 Run Scope

The two types of projects are Newly Constructed or Addition and/or Alteration [NOTE: for addition alone analysis, select Newly Constructed, check Addition Alone, and enter the Fraction of a dwelling unit (Addition Area / (Existing + Addition) = Fraction)] .

4.4 Building

The Building tab (see Figure 4-3) is used to provide basic information about the building.

Figure 4-3: Building Information

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4.4.1 Building Information

4.4.1.1 Building Description

The building description will appear as the second line of general project information on the CF1R. It is a user-defined label and is different from the project name.

4.4.1.2 Air Leakage

Default value (no blower door test) for buildings with space conditioning ducts in unconditioned space (and the default condition for no cooling) is 5 for single family and 7 for other buildings. When there are no heating and/or cooling system ducts in unconditioned space, the default is 4.4 for singlefamily buildings and townhomes and 6.2 for all others buildings.

If a single family or town home will have HERS verified infiltration testing (blower door test), model an achievable target leakage area value. For multi-family buildings there is no compliance option for infiltration testing.

When a value lower than default is modeled, diagnostic testing for reduced infiltration, with the details and target values modeled, is reported as a HERS Required Verification on the CF1R.

This input represents the air flow through a blower door at 50 pascals (Pa) of pressure measured in cubic feet per minute, called CFM50 or ACH50. CFM50 x 60 minutes divided by the volume of conditioned space is the air changes per hour at 50 Pa, called ACH50.

4.4.1.3 Insulation Construction Quality

The presence of improved/verified high quality insulation installation certified by the installer and field verified to comply with RA3.5. Default value is “standard.” Specify either standard (unverified) or improved, which means verified high quality insulation installation. Also called Quality

Insulation Installation (QII), improved requires HERS verification. Credit for verified quality insulation installation is applicable to all insulated assemblies in the building—ceilings/attics, knee walls, exterior walls and exterior floors. See Reference Appendices, Residential Appendix RA3.5.

4.4.1.4 Front Orientation

This field defines the front orientation in degrees and must be accurate within 5 degrees. This value

is from the site plan, and differs from the window and wall orientation (see Section 7.1). While this

input is typically the side of the building where the front door is located, if the front door, front façade, or the side of the building facing the street are different, any choice is acceptable as long as the end result is a CF1R with windows facing the correct orientationactual azimuth .

The front orientation or actual azimuth is used to establish the orientation of walls and windows, which are modeled using either labels such as “front” or “left,” or the orientation with respect to the front and plan azimuth,

not the actual orientation (see Orientation in Section 7.1).

Multiple orientation (or cardinal compliance) is a valid selection for subdivisions where homes may be built in any orientation. The building must comply with the same energy features in all

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orientations. A single CF1R will display the compliance for the four cardinal orientations—north, east, south and west.

4.4.1.5 Single Family or Multi-family

Use the check box to indicate if the building is a single-family dwelling (R-3 occupancy group), or is a multi-family building (R-1 or R-2 occupancy group) with three stories or less. When multi-family is selected, the dwelling unit information is defined under the separate dwelling unit tab. This structure allows for modeling different dwelling unit configurations within a single building with unique HVAC, ventilation and water heating conditions.

Multi-family buildings can be modeled with each dwelling unit as a separate zone (the most detailed and complex) or with each floor as a separate zone. A 2-story, two zone sample file is included with

CBECC-Res. This structure requires the dwelling units be defined separately for each floor. For example, if there are 1-bedroom and 2-bedroom configurations on both the first floor and second

floor, they must be identified separately under the dwelling unit tab (see Section 4.4.1.10). For

additional guidance, see Section 5.4.1.10 for structuring the HVAC system inputs, and Section 5.5 for

information about defining the garage zone in a multi-family building. Party walls or a party floor must be modeled as an interior surface, with the box checked to indicate a different dwelling unit is on the other side of the surface being modeled.

4.4.1.6 Number of Bedrooms

The number of bedrooms in a building is used to establish mechanical ventilation requirements and to determine if a building qualifies as a compact building for purposes of incentive programs. For single family dwellings, indicate the number of bedrooms under the building tab and for multifamily dwellings under the dwelling unit tab.

4.4.1.7 Natural Gas Availability

Check the box if natural gas is available at the building site. The field does not indicate what fuel type is being used in the building for heating, cooling or water heating. Whether natural gas is available determines the fuel type used as the basis for time dependent value (TDV) in the standard design (see Reference Appendices, Joint Appendix JA3).

4.4.1.8 Zonal Control

Checking this box enables modeling a building that meets zonal control requirements of the heating system. Zonal control credit requires compliance with several eligibility criteria (see Residential

Compliance Manual, Chapter 4, Section 4.5.2 for the complete list). The living and sleeping areas are modeled and conditioned separately, with either zonally-controlled equipment or separate space conditioning equipment, and with living and sleeping schedules for the thermostat settings.

Some of the requirements for this compliance option include each habitable room must have a source of space conditioning, the sleeping and living zones must be separately controlled, a non-closeable opening between the zones cannot exceed 40 ft 2 , each zone must have a temperature sensor and a setback thermostat, and the return air for the zone must be located within the zone.

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4.4.1.9 Has Attached Garage

This check box is used to indicate if there is an attached garage, which must be modeled. While there are no minimum requirements for the garage construction, it is modeled to accurately represent the building to be constructed and typically improves compliance due to the buffering effects of an enclosed attached space.

4.4.1.10 Dwelling Units

In a multi-family building, the dwelling unit information is identified under this tab (see Figure 4-4).

For single family dwelling units the characteristics are defined under the Building tab.

Figure 4-4: Multi-Family Dwelling Unit Details

Each dwelling unit type must be separately identified. A dwelling unit type will have the same floor area, number of bedrooms, appliances (only the presence of clothes washer and dryer can be shut off), the same IAQ ventilation system type, and be located on the same floor. Identify each dwelling unit type and the number of that dwelling unit type that is included in the building or zone (see

Figure 4-4).

4.4.2 Dwelling Unit Details, Multi Family

4.4.2.1 Unit

This is a short distinguishing piece of information to describe the dwelling unit.

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4.4.2.2 Count

This input is to specify how many of this dwelling unit type are included in this zone. In the above figure, the bottom floor has 780 x 4 = 3120 ft 2 .

4.4.2.3 # Bedrooms

Number of bedrooms in the dwelling unit used to establish the minimum ventilation requirements.

4.4.2.4 Zone & Area/Unit

The zone name is entered here. Multi-family buildings that have floors between dwelling units, must either define each floor as a separate zone or each dwelling unit as a separate zone. In this example, each floor is defined as a separate zone, with four dwelling units per zone.

4.4.2.5 Ft

2

The number of square feet in the one dwelling unit type being defined.

4.4.2.6 IAQ (Indoor Air Quality) Ventilation

Used to identify that a default minimum IAQ fan is being used or another method of meeting the mandatory ventilation requirement.

4.4.2.7 Zone

The zone in which the dwelling unit is modeled.

4.5 Lighting/Appliances

The inputs under these tabs are for project types other than energy compliance for new construction.

4.6 IAQ Ventilation

For single-family dwelling units, the mandatory indoor air quality (IAQ) ventilation is specified here.

The minimum required ventilation rate is provided based on the conditioned floor area and number

of bedrooms in the dwelling unit. See Section 8.6 for more information on the specific IAQ fan

details. For more information on this mandatory requirement, see Residential Compliance Manual,

Section 4.6.

4.6.1.1 Model as

Select method of ventilation as either default minimum IAQ fan or specify individual fans (as

described in Section 8.6).

4.6.1.2 Zone

Assign to one of the conditioned zones.

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4.7 Cooling Ventilation

Figure 4-5: Cooling Ventilation

Project

Cooling ventilation systems use fans to bring in outside air to cool the house when this could reduce cooling loads and save energy. The simplest approach is a whole house fan, which is the basis of the standard design in climate zones 8-14 where the evenings may cool down enough to be an effective

means of cooling the house. The types of cooling ventilation are shown in Table 4-2. Additional

inputs are discussed in Section 8.7.

4.7.1.1 Cooling Ventilation

Default value is none. Other options are a default prescriptive whole house fan (will set to exactly 2

CFM/ft 2 ), specify individual fans, or a central fan integrated system which uses the space conditioning duct system to provide outside air for cooling (additional inputs are discussed in

Chapter 8). Whole house fan operation requires that the building have an attic.

Table 4-2: Ventilation Cooling Fans

Measure

Whole House Fan

CFI (Central Fan

Integrated) cool vent

Description

Traditional whole house fan is mounted in the ceiling to exhaust air from the house to the attic, inducing outside air in through open windows. Whole house fans are assumed to operate between dawn and 11 PM only at 25% of rated CFM to reflect manual operation of fan and windows by occupant.

Fans must be listed in the California Energy Commission’s Whole House

Fan directory. If multiple fans are used, enter the total CFM.

These systems use the furnace or air handler fan to deliver outdoor air to conditioned space. With an automated damper, outside air duct, temperature sensors and controls, these systems can automatically deliver filtered outdoor air to occupant set comfort levels when outdoor conditions warrant the use of ventilation.

4.7.1.2 Zone

Assign to any conditioned zone that has a ceiling below an attic. Since a whole house fan uses attic venting to exhaust the hot air, an attic is required for this measure.

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Zones

Chapter 5. Zones

5.1 Multiple Conditioned Zones

Decide in advance how many zones are needed to adequately define a building. A zone is typically an area with specific details that require it to be modeled separately from another area (a more complex building model does not necessarily yield better compliance results).

Some cases where multiple zones are required are:

• When taking credit for zonal control (with at least one living and one sleeping zone).

• Spaces are served by different types of heating/cooling equipment (such as a heat pump and a gas furnace)

• Different duct conditions or locations.

• A radiant barrier in part of an attic, and not in another part.

The simplest approach is to model the worst case in a single zone, but a more detailed model may be needed to achieve compliance.

NOTE: Different types of water heating can be modeled within the same zone.

In addition to the conditioned zones, attics, garages, attached unconditioned spaces and crawl spaces zones must be modeled.

5.2 Attic

The compliance software models attics as a separate thermal zone and includes the interaction with the air distribution ducts, infiltration exchange between the attic and the house, the solar gains on the

roof deck and other factors. These interactions are illustrated in Figure 5-1.

5.2.1 Attic Zone Data

The software automatically creates an attic zone once you define a ceiling below an attic as part of

the conditioned space or garage (see Figure 5-2).

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Figure 5-1: Attic Model Components

Roof Deck

Convection & Radiation

Solar

Vent

Vent

Duct

Attic

Ceiling

House

Conduction & Infiltration

Figure 5-2: Attic Zone Data

Zones

5.2.1.1 Name

User-defined name. If the building plans have a unique identifier, that should be used here to assist in the plan checking and inspection processes.

5.2.1.2 Attic Conditioning

The conditioning is either ventilated (typical attic) or conditioned (unvented) , which is not yet implemented .

5.2.1.3 Roof Rise

Specify the roof rise or roof pitch, which is the number of feet the roof rises in a span of 12 feet

(shown on elevations as 4:12 or 4 in 12). If there are multiple pitches you can enter the roof rise of the largest area of roof.

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5.2.1.4 Area

The area is not a user input. The area is derived from the combination of ceilings below attic modeled as part of the conditioned and unconditioned zones.

5.2.1.5 Attic Status

Default is new. Other options include altered and existing for Existing+Addition+Alteration analysis.

5.2.1.6 Construction

The roof construction is the connection to an assembly that contains the roofing material (such as tile

or asphalt shingles), radiant barrier, and other construction details (see more in Chapter 6,

Construction Assemblies).

5.2.1.7 Solar Reflectance

The default aged solar reflectance is 0.10 for all roof types. The aged solar reflectance for a roof product , as published by the Cool Roof Rating Council (CRRC) (www.coolroofs.org) , or calculated from the initial value using the equation in 3.7.1 of the 2013 Residential Compliance Manual. The aged solar reflectance measures the roofing product’s ability to reflect solar heat. A higher value is better for warmer climates, so if a specific product color is unknown use a lower value among options to avoid having to recalculate compliance during construction.

If the roof membrane has a mass of at least 25 lb/ft 3 or any roof area that incorporates integrated solar

collectors, the roof may assume the Package A solar reflectance value (see Section 5.2.2).

If the roof is a cathedral ceiling or rafter roof, the solar reflectance is defined as part of the ceiling (see

Chapter 7, Building Envelope).

The roofing material and roof structure is specified via the Roof Deck/Surface: Construction, which is accessed under construction assemblies or by creating a new roof construction assembly as

discussed in Chapter 6, Construction Assemblies.

5.2.1.8 IR Emittance

The default infrared or thermal emittance (or emissivity) for all roofing materials is 0.85. Otherwise, enter the emittance value published by the Cool Roof Rating Council (CRRC) (www.coolroofs.org).

If the roof membrane has a mass of at least 25 lb/ft 3 or for any roof area that incorporates integrated

solar collectors, the roof may assume the Package A emittance value (see Section 5.2.2).

If the roof is a cathedral ceiling or rafter roof, the emittance is defined as part of the ceiling (see

Chapter 7, Building Envelope).

The roofing material and roof structure is specified via the Roof Deck/Surface: Construction which is accessed under construction assemblies or by creating a new roof construction assembly which is

discussed in Chapter 6, Construction Assemblies.

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5.2.2 Cool Roof

Cool roof is a term that refers to the ability of roofing materials to both reflect and absorb solar heat.

It typically means a high solar reflectance and a high emittance, but can also be a low emittance and a very high solar reflectance.

Although specific values are not mandatory, Package A (the basis of the standard design) contains a minimum requirement for solar reflectance and emittance that varies by climate zone and roof slope.

A low slope roof has a ratio of rise to run (or pitch) of 2 in 12 or less (<9.5 degrees from the horizontal). In climate zones 13 and 15 a low slope roof is compared to a roof with 0.63 aged solar reflectance and 0.75 emittance. A steep slope roof has a ratio of rise to run of greater than 2:12 (>9.5 degrees from the horizontal). In climate zones 10 through 15 a steep slope roof is compared to a roof with 0.20 aged solar reflectance and 0.75 emittance.

The CF1R reflects that a cool roof is modeled when a reflectance of greater than 0.20 is modeled. If a reflectance value greater than 0.10 but less than or equal to 0.20 is modeled, the CF1R reflects a special features message that the building contains a non-standard roof reflectance.

5.2.3 Low Slope Aggregate Roof

Although more common in nonresidential applications, aggregate is a roofing product made up of stone or gravel material that is used as a finish surface for low-sloped roofing. A compliance option

(see Publication CEC-400-2012-018-SF) allows for default efficiencies when the material is tested to

the initial solar reflectance value shown in Table 5-1. The compliance option allows compliance using

the default values for aged solar reflectance and emittance values shown in the table.

Table 5-1: Solar Reflectance and Emittance for Aggregate Materials

Tested Initial Solar

Reflectance

Default Aged Solar

Reflectance Default Emittance Aggregate Size

Built-Up Roofs

Size 6-8 confirming to

ASTM D448 and D1863

Ballasted Roofs

Size 2-4 confirming to

ASTM D448

0.50

0.45

0.48

0.40

0.85

0.85

5.3 Crawl Space

The software automatically creates a crawl space zone when a floor over crawl space is defined. The

floor characteristics are more fully discussed in Chapter 6, Construction Assemblies).

The crawl space zone (see Figure 5-3) is created using the area specified for the raised floor above the

crawl space and the floor elevation to set the area and height of the crawl space.

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Figure 5-3: Crawl Space Zone

Zones

5.3.1 Crawl Space Zone Data

5.3.1.1 Crawl Space Name

User-defined name. If the building plans have a unique identifier, that should be used here to assist in the plan checking and inspection processes.

5.3.1.2 Crawl Space Type

The default type is a vented crawl space. The three available types are (1) normal vented crawl space

(has a conditioned space above with raised floor insulation), (2) insulated with reduced ventilation

[as used in the Building Code], or (3) sealed and mechanically ventilated crawl space (also called a controlled ventilation crawl space or CVC). For CVC credit installation requirements see Reference

Appendices, Residential Appendix RA 4.5.1.

5.3.1.3 Crawl Perimeter

The length (in feet) of the perimeter (similar to the slab edge length for a slab on grade floor).

5.3.1.4 Crawl Height

The depth of the crawl space, in feet.

5.4 Conditioned Zone

To create the house or dwelling unit, right-click on project or edit an existing conditioned zone (see

Figure 5-4).

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Figure 5-4: Conditioned Zone Data

Zones

5.4.1 Conditioned Zone Data

5.4.1.1 Name

User-defined name. If the building plans have a unique identifier, that should be used here to assist in the plan checking and inspection processes.

5.4.1.2 Zone Status

The default is new for new construction or the added floor area of an addition. Other options include altered and existing.

5.4.1.3 Type

The default zone type is conditioned. If the building is designated as meeting the zonal control criteria (under the building tab), the type is defined as living or sleeping. For more information on

zonal control see Section 8.1.2.

5.4.1.4 Floor Area

Specify the floor area and the number of stories in the zone (not the building) and the average ceiling height.

5.4.1.5 Number of Stories

The number of stories in the zone. If each floor of a 2-story home is modeled as a separate zone, the number of stories is 1 for each zone. If the home is modeled as a single zone, then this value is 2.

5.4.1.6 Ceiling Height

Average ceiling height, in feet.

5.4.1.7 Floor to Floor

Distance between the floor being modeled and any floor above. Default value is average ceiling height plus one foot.

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Zones

5.4.1.8 Bottom

Distance above grade of the surface of the floor (in feet). Slab floor will be the height from the grade to the top of the slab. Raised floor will be the height from grade to the top of the raised floor.

For multi-story buildings where the second or third floors are modeled as a separate zone, the bottom must be the total distance from grade to the bottom of the floor (e.g., if the first floor is at 0.7 feet, with 9 foot ceilings, and 10 feet as the floor to floor height, the second floor bottom is 10.7).

5.4.1.9 Window Head Height

Default value is based on the average ceiling height.

5.4.1.10 HVAC System

Identify the name of the heating, ventilating and air conditioning (HVAC) system by picking a defined system or creating a new system. The system is made up of the heating, cooling and

distribution systems, and a furnace fan. See more in Chapter 8, Mechanical Systems.

In a multi-family building each floor must have at least one HVAC system (if the system characteristics are the same, use the copy/paste feature).

5.4.1.11 DHW System 1

Identify the name of the domestic water heating (DHW) system by picking a defined system or

creating a new system. See more in Chapter 9, Domestic Hot Water.

5.4.1.12 DHW System 2

Identify a second DHW system or none.

5.5 Garage

An attached unconditioned space is modeled as a separate unconditioned zone. When the project

was defined as having an attached garage, the software created an unconditioned zone (see Figure

5-5). The buffering effect of this zone is modeled to accurately represent the building.

The walls between the house and garage are modeled as part of the conditioned space as an interior

wall. For details on modeling the walls, ceiling, slab floor and garage door, see Chapter 6,

Construction Assemblies and Chapter 7, Building Envelope.

When a multi-family building is modeled as having an attached garage, the software creates only one unconditioned garage zone. To represent a garage attached to each unit increase the size of the single garage zone to have the area and all the surfaces of all the garages combined.

5.5.1.1 Party Walls

For multi-family building party walls between conditioned zones you need to check the "Different

Dwelling Unit on Other Side" for each of those walls (and floors).

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5.5.2 Garage Zone Data

Figure 5-5: Garage Zone Data

Zones

5.5.2.1 Garage Name

User-defined name. If the building plans have a unique identifier, that should be used here to assist in the plan checking and inspection processes.

5.5.2.2 Area

The area of the garage or unconditioned space, in square feet (ft 2 ).

5.5.2.3 Volume

Volume of the space in cubic feet (ft 3 ) .The program defaults the volume based on the average ceiling height defined for the conditioned zone.

5.5.2.4 Bottom

Floor elevation or distance above grade of the surface of the floor (in feet).

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Chapter 6. Construction Assemblies

CBECC-Res does not use the assembly U-factors from the Reference Appendices, Joint Appendix 4.

Instead, assemblies are created inside the program. As you build an assembly, the screen displays a

U-factor and R-value only as a guide for the user to see how the assembly compares to the standard design assembly (Section 150.1(c), Table 150.1-A, Package A). Model the closest insulation R-value without exceeding the product’s R-value. The U-factor is not reported on the CF1R. Only the insulation R-values and construction details are reported.

In addition to typical wood-frame construction, CBECC-Res can model wood framed walls with advanced wall framing (AWF), steel-frame construction, concrete, masonry, insulated concrete form

(ICF), brick, log, strawbale, and structurally insulated panels (SIPs).

6.1 Cavity R-Value

When completing assemblies, use the compressed product R-value for the cavity space (Table 6-1).

Nominal

Lumber

Size

2x12

2x10

2x8

2x6

2x4

2x3

2x2

2x1

Standard Product

Thickness

1-1/2”

3/4"

Cavity

Depth

11-1/4”

9-1/4”

7-1/4”

5-1/2”

3-1/2”

2-1/2”

R-38

37

32

27

12”

Table 6-1: Compressed Insulation R-values

Compressed R-value Inside Cavity for Product Rated as…

R-38C

38

35

30

R-30 R-30C R-25

30

30

25

21

30

27

22

10-1/4” 9-1/2” 8-1/4”

25

24

20

8”

R-22

22

19

14

6-3/4”

R-21C

21

21

15

R-19

19

18

13

R-15C R-13

15

11

13

10

6.6 6.2

5-1/2” 6-1/4” 3-1/2” 3-1/2” 3-1/2”

R-11

11

8.9

6.2 Assembly Types

The types of assemblies that can be created in the program are:

Exterior wall

Interior wall (also used for demising walls or walls between house and garage)

Attic roof

Cathedral roof

Ceiling below attic

Interior floor

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Exterior floor

Floor over crawl space

Also included are some typical assemblies:

T24-2013 exterior wall wood 2x4

T24-2013 R38 ceiling below attic

T24-2013 R30 ceiling below attic

T24-2013 R19 exterior floor

T24-2013 R19 floor over crawl

T24-2013 R15 interior wall

T24-2013 R19 interior floor

Construction Assemblies

6.3 Mandatory Envelope Requirements

The mandatory roof insulation requirement in new construction is a wood-framed ceiling or rafter roof with R-30 (Section 150.0(a)), or a weighted average U-factor of 0.031 (formerly R-19).

The mandatory floor insulation requirement is a wood-framed raised floor (Section 150.0(d)) with R-

19, or a weighted average U-factor of 0.037 (formerly R-13).

Under the Help button is a summary of the minimum mandatory requirements for opaque surfaces.

6.4 Spray Foam Insulation (SPF)

The R-values for spray applied polyurethane foam insulation differ depending on whether the product is closed cell (default R-5.8/inch) or open cell (default R-3.6/inch). When completing a

construction assembly for the roof/ceiling, walls, or floor, use the values shown in Table 6-2 to

determine the default R-value for the cavity size. Alternatively, with HERS verification and additional documentation requirements, a higher than default value may be used, as indicated by checking the box for non-standard spray foam in cavity as part of the construction assembly (see

Reference Appendices, Residential Appendix RA3.5.6).

Table 6-2: Required Thickness Spray Foam Insulation

Required R-values for SPF insulation R-11 R-13 R-15 R-19 R-21 R-22 R-25 R-30 R-38

Required thickness closed cell @ R5.8/inch 2.00 inches

2.25 inches

2.75 inches

3.50 inches

3.75 inches

4.00 inches

4.50 inches

5.25 inches

6.75 inches

Required thickness open cell @ R3.6/inch 3.0 inches

3.5 inches

4.2 inches

5.3 inches

5.8 inches

6.1 inches

6.9 inches

8.3 inches

10.6 inches

To receive the most credit, spray foam insulation may be combined with improved construction

quality, which is modeled at the project level (see Section 4.4.1.3) and requires HERS verification

(Reference Appendices, Residential Appendix RA3.5).

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Construction Assemblies

6.4.1 Medium Density Closed-Cell SPF Insulation

The default R-value for spray foam insulation with a closed cellular structure is R-5.8 per inch, based on the installed nominal thickness of insulation. Closed cell insulation has an installed nominal density of 1.5 to less than 2.5 pcf.

6.4.2 Low Density Open-Cell SPF Insulation

The default R-value for spray foam insulation with an open cellular structure is calculated as an R-

3.6 per inch, calculated based on the nominal required thickness of insulation. Open cell insulation has an installed nominal density of 0.4 to 1.5 pounds per cubic foot (pcf).

6.4.3 Advanced Wall Framing

Advanced wall framing (AWF) is applicable to wood framed walls that meet the installation criteria from Reference Appendices, Joint Appendix JA 4.1.6 to reduce the amount of wood used for framing..

The construction technique, also referred to as an advanced wall system, incorporates the following construction techniques: 24-inch on center framing, eliminates intermediate framing for cripple and king studs, uses single top plates, double stud corners, and in-line (i.e., stack) framing to maintain continuity of transferring live loads of roof framing to wall framing (which allows roof sheathing and exterior siding to be installed at full widths), reduces framing for connections at interior partition walls (i.e., T-walls), and reduces window and door header sizes.

6.5 Attic Roof Terminology

6.5.1 Attic

Attic is an enclosed space directly below the roof deck and above the ceiling beams. The attic component of the building contains the roof and attic, and any insulation that occurs at the roof deck.

In CBECC-Res, the attic is a separate zone. A typical attic does not include the ceiling or ceiling insulation which is modeled as part of the ceiling below attic.

6.5.2 Cathedral Ceiling

A cathedral ceiling or rafter roof is modeled when there is no attic above with a ceiling below. A cathedral ceiling typically has insulation installed between the rafters and may be flat or sloped. The insulation is in contact with the ceiling and there is typically a one-inch air gap above the insulation so that moisture can be vented. Whether there is an air space required above the insulation, or the entire cavity is filled with insulation with no venting, is up to the local building official.

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6.5.3 Ceiling Below Attic

The ceiling is defined as the interior upper surface of a space separating it from an attic, plenum, indirectly or directly conditioned space or the roof assembly, which has a slope less than 60 degrees from horizontal (definition from Reference Appendices).

6.5.4 Knee Wall

A knee wall is a sidewall separating conditioned space from attic space under a pitched roof. Knee walls are modeled in CBECC-Res as an interior wall (although actually a demising surface) and are insulated as an exterior wall.

6.5.5 Low Slope Roof

A low slope roof has a ratio of rise to run (or pitch) of 2 in 12 or less (<9.5 degrees from the horizontal). Although a specific value is not mandatory, the standard design for a low slope roof in climate zones 13 and 15 is a 0.63 aged solar reflectance.

If the roof membrane has a mass of at least 25 lb/ft 3 or the roof area incorporates integrated solar collectors, the roof may assume the standard design value for solar reflectance (exceptions to Section

150.1(c)11).

6.5.6 Radiant Barrier

A radiant barrier installed below the roof decking reduces radiant heat to any ducts and insulation below. While not a mandatory requirement, the standard design used to establish a building’s energy budget has a radiant barrier in climate zones 2-15. Installation requirements for a radiant barrier (see CF2R form) require the radiant barrier in the garage/unconditioned space if a radiant barrier is installed in the attic over conditioned space and that same attic is over the unconditioned space.

6.5.7 Roof

A roof is defined as the outside cover of a building or structure including the structural supports, decking, and top layer that is exposed to the outside with a slope less than 60 degrees from the horizontal.

When Package A (the basis of the standard design) contains a minimum requirement for solar reflectance and emittance, the values vary by roof slope. A low slope roof has a ratio of rise to run (or pitch) of 2 in 12 or less (<9.5 degrees from the horizontal). A steep slope roof has a ratio of rise to run of greater than 2:12 (>9.5 degrees from the horizontal). Although there is no mandatory cool roof requirement, these are the characteristics used to establish the standard design, so there will be an energy penalty when default roof values are used.

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Construction Assemblies

6.5.8 Steep Slope Roof

A steep slope roof has a ratio of rise to run of greater than 2:12 (>9.5 degrees from the horizontal).

Although a specific value is not mandatory, the standard design for climate zones 10 through 15 is an aged solar reflectance of 0.20.

If the roof membrane has a mass of at least 25 lb/ft 3 or the roof area incorporates integrated solar collectors, the roof may assume the standard design value for solar reflectance (exceptions to Section

150.1(c)11).

6.6 Attic Construction

Attic constructions are accessed by creating a new attic roof construction, or modifying an existing assembly in the list of Construction Assemblies.

6.6.1 Attic Construction Data

6.6.1.1 Construction Name

User-defined name. If the building plans have a unique identifier, that should be used here to assist in the plan checking and inspection processes.

6.6.1.2 Can Assign To

This is a fixed field. To create a new assembly type, at the zone level, select <create> and pick the appropriate construction assembly type.

Figure 6-1: Attic Construction Data

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6.6.1.3 Construction Type

Options are wood framed , or built up roof , steel framed, and SIPs .

6.6.1.4 Roofing Type

Pick the appropriate roof type as either (1) steep slope roof tile, metal tile, or wood shakes, or (2) all other.

6.6.2 Construction Layers

Working from the top to the bottom of the construction layers:

6.6.2.1 Roofing

The available types will depend on the roofing type specified. Types include light roof, roof tile, asphalt, gravel, tile, heavy ballast or pavers, and very heavy ballast or pavers.

6.6.2.2 Above Deck Insulation

If above deck insulation is shown as part of the attic details, model the R1 through R8to R60 insulation.

6.6.2.3 Roof Deck

The default is wood siding/sheathing/decking.

6.6.2.4 Cavity/Frame

List the compressed R-value of cavity insulation (see Section 6.1) in the cavity column.

This is the insulation that is installed at the roof. Typical insulation is modeled as part of the ceiling below attic.

The framing column is to indicate the size and spacing of the framing . Options are 2x4 to 2x12 with

16- or (e.g., 2x4 with 24-inch on center framing).

6.6.2.5 Inside Finish

This is the inside finish (if any), of the attic space, and does not include the ceiling below the attic. A layer of gypsum is not typically included.

6.6.2.6 Non-Standard Spray Foam in Cavity

This check box identifies additional documentation and HERS verification requirements due a claimed R-value that exceeds the default assumption of R-5.8 per inch for closed cell and R-3.6 per

inch for open cell (see Section 6.4).

6.6.2.7 Radiant Barrier Exposed on the Inside

This check box identifies whether a radiant barrier is being installed in the attic.

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6.7 Ceiling Below Attic and Interior Ceilings

Figure 6-2: Ceiling Below Attic Data

Construction Assemblies

The Construction called “Ceiling below attic cons” in Figure 6-2 is accessing the construction

assembly shown in Figure 6-3.

6.7.1 Ceiling Below Attic Construction Data

6.7.1.1 Construction Name

User-defined name. If the building plans have a unique identifier, that should be used here to assist in the plan checking and inspection processes.

6.7.1.2 Can Assign To

This is a fixed field. To create a new assembly type, at the zone level, pick create and make the appropriate construction assembly type.

6.7.1.3 Construction Type

Options are wood or steel framed and SIPsor built up roof .

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Figure 6-3: Ceiling Below Attic Assembly

Construction Assemblies

6.7.2 Construction Layers

6.7.2.1 Attic Floor

The available types include no attic floor and wood siding/sheathing/decking.

6.7.2.2 Cavity/Frame

List the compressed R-value of cavity insulation (see Section 6.1) in the cavity column. In the framing

column select the size of the framing and the spacing, such as 2x12 with 24-inch on center framing, or

2x4 roof truss at 24-inches on center.

6.7.2.3 Sheathing/Insulation

List the sheathing or insulation layer. Options are none, gypsum board, wood sheathing, and R1 through R12to R60 insulation.

6.7.2.4 Inside Finish

This is the inside finish (if any), of the attic space, and does not include the ceiling below the attic. A layer of gypsum is not typically included.

6.7.2.5 Non-Standard Spray Foam in Cavity

This check box identifies additional documentation and HERS verification requirements due a claimed R-value that exceeds the default assumption of R-5.8 per inch for closed cell and R-3.6 per

inch for open cell (see Section 6.4).

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Construction Assemblies

6.7.2.6 Raised Heel Truss

Check box to indicate if there is a raised heel truss and its height (in inches). With a standard roof

truss (Figure 6-4) the depth of the ceiling insulation is restricted to the space left between the roof

deck and the wall top plate for the insulation path and the space between the bottom and top chord of the truss in the framing path. If the modeled insulation completely fills this space, there is no attic air space at the edge of the roof. Heat flow through the ceiling in this attic edge area is directly to the outside both horizontally and vertically, instead of to the attic space.

Figure 6-4: Section at Attic Edge with Standard Truss

A raised heel truss (Figure 6-5) provides additional height at the attic edge that, depending on the

height and the ceiling insulation, can either reduce or eliminate the attic edge area and its thermal impact.

Figure 6-5: Section at Attic Edge with a Raised Heel Truss

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6.7.3 Cathedral Ceiling Construction Data

Each surface facing a different orientation will be modeled as a separate surface (see Figure 6-7 and

Section 6.7.5).

Figure 6-6: Cathedral Ceiling

6.7.3.1 Construction Name

User-defined name. If the building plans have a unique identifier, that should be used here to assist in the plan checking and inspection processes.

6.7.3.2 Can Assign To

This is a fixed field. To create a new assembly type, at the zone level, pick create and make the appropriate construction assembly type.

6.7.3.3 Construction Type

Options are wood framed , or built up roof , steel framed, and SIPs .

6.7.3.4 Roofing Type

Pick the appropriate roof type as either (1) steep slope roof tile, metal tile, or wood shakes, or (2) all other.

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6.7.4 Construction Layers

6.7.4.1 Roofing

The available types include no attic floor and wood siding/sheathing/decking.

6.7.4.2 Above Deck Insulation

If above deck insulation is shown as part of the attic details, model the R1 to R 860 insulation.

6.7.4.3 Roof Deck

The default is wood siding/sheathing/decking.

6.7.4.4 Cavity/Frame

List the compressed R-value of cavity insulation (see Section 6.1) in the cavity column. The framing

column is to indicate the size of the framing and the spacing (e.g., 2x12 with 24-inch on center framing). Also included is an option for a 2x4 bottom chord of truss at 24-inches on center.

6.7.4.5 Sheathing/Insulation

List the sheathing or insulation layer. Options are none, gypsum board, wood sheathing, and R1 to

R 860 insulation.

6.7.4.6 Inside Finish

This is the inside finish (if any), of the roof. A layer of gypsum is typically included.

6.7.4.7 Non-Standard Spray Foam in Cavity

This check box identifies additional documentation and HERS verification requirements due a claimed R-value that exceeds the default assumption of R-5.8 per inch for closed cell and R-3.6 per

inch for open cell (see Section 6.4).

6.7.5 Cathedral Ceiling Data

Once you have an assembly to match your building and select <OK>, the screen shown in Figure 6-7

appears allowing you to complete the data for the roof assembly. Each surface facing a different orientation is modeled as a separate surface.

6.7.5.1 Ceiling Area

The area of the ceiling (in square feet) that meets all the same specified criteria. If parts of the roof face different orientations, they must be modeled separately.

6.7.5.2 Roof Rise

Specify the roof rise or roof pitch, which is the number of feet the roof rises in a span of 12 feet (may be shown as 4:12 for a roof rise of 4 feet in 12 feet). If there are multiple pitches you can enter the roof rise of the largest area of roof.

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Figure 6-7: Cathedral Ceiling Data

Construction Assemblies

6.7.5.3 Orientation

The plan view using labels front, left back and right or specify a value based on front = 0, left = 90, back = 180, and right = 270. If the cathedral ceiling is on a part of the building facing an angle, match

the orientation of the walls. For more on orientation and plan azimuth, see Section 7.1.

6.7.5.4 Solar Reflectance

The default aged solar reflectance is 0.10 for all roof types. Alternatively, enter the aged solar reflectance for a roof product as published by the Cool Roof Rating Council (CRRC)

(www.coolroofs.org). If only an initial value is available, calculate the aged value using the equation in 3.7.1 of the 2013 Residential Compliance Manual. A higher value is better, so if a specific product color is unknown use a lower value among options to avoid having to regenerate compliance during

construction. See also Section 5.2.1.7.

6.7.5.5 IR Emittance

The default infrared or thermal emittance (or emissivity) for all roofing materials is 0.85.

Alternatively, enter the emittance is the value published by the Cool Roof Rating Council (CRRC)

(www.coolroofs.org). See also Section 5.2.1.8.

6.8 Walls

Wall constructions are accessed by creating a new wall inside the conditioned zone or modifying an

existing assembly in the list of Construction Assemblies. Walls (Figure 6-8) are defined from the

inside surface to the outside. Interior walls are modeled the same as exterior walls. For a description of when a wall is modeled as interior (for example, demising or walls separating the house from the

garage), see Section 6.8.5.

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6.8.1

Interior and

Exterior Wall Construction Data

6.8.1.1 Construction Name

User-defined name.

6.8.1.2 Can Assign To

This is a fixed field. To create a new assembly type, at the zone level pick <create> and select the appropriate construction assembly type.

6.8.1.3 Construction Type

Options available include wood frame d, and steel frame

d (section 6.8.2)

, unframed wall types are concrete, Insulated Concrete Form (ICF), brick, hollow unit masonry, adobe, strawbale, log (section

6.8.3), and

structurally insulated panel s (SIP s )

(section 6.8.4)

. [Limited during program development to wood frame.]

Figure 6-8: Wood-Framed Wall Construction Data

6.8.2

Framed Wall

Construction Layers (inside to outside)

6.8.2.1 Inside Finish

Default value gypsum board.

6.8.2.2 Sheathing/Insulation

List the sheathing or insulation layer in a wall on the inside surface (conditioned space side) of the framingframed wall, or the size and material of furring on the inside surface . Options are none, gypsum board, wood sheathing, and R 1to R 12 60 insulation.

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6.8.2.3 Cavity/Frame

List the compressed R-value of cavity insulation (see Section 6.1) in the cavity column. The framing

column is to indicate the size of the framing and the spacing (e.g., 2x6 with 16-inch on center framing)

, or advanced wall framing (AWF), see Section 6.4.3

.

6.8.2.4 Sheathing/Insulation

List the sheathing or insulation layer on the outside of the framing. Do not enter 1-coat stucco here.

Options are none, gypsum board, wood sheathing, and R 1to R 12 60 insulation.

6.8.2.5 Exterior Finish

Exterior finish options are wood siding, 3 coat stucco, or R4 synthetic stucco (also known as 1-coat stucco).

6.8.2.6 Non-Standard Spray Foam in Cavity

This check box identifies that additional documentation and HERS verification requirements apply because the claimed R-value exceeds the default assumption of R-5.8 per inch for closed cell and R-

3.6 per inch for open cell (see Section 6.4).

6.8.3

Mass or Other Unframed Walls

6.8.3.1 Inside Finish

Default value gypsum board.

6.8.3.2 Insulation/Furring

List the insulation installed if the walls are furred on the inside. Select the thickness and type of furring which is 0.5-inch to 5.5-inch thick wood or metal.

6.8.3.3 Mass Layer

List the material which varies based on the construction type and includes concrete, brick, light weight (LW), medium weight (MW) or normal weight (NW) concrete masonry units (CMU) with solid grout, insulated cores, or empty cores. Select the thickness.

6.8.3.4 Insulation/Furring

List the insulation installed if the walls are furred on the outside. Select the thickness and type of furring which is 0.5-inch to 5.5-inch thick wood or metal.

6.8.3.5 Exterior Finish

Exterior finish options are wood siding, 3 coat stucco, or R4 synthetic stucco (also known as 1-coat stucco) and wood siding/sheathing/decking.

6.8.3.6 Non-Standard Spray Foam in Cavity

This check box identifies that additional documentation and HERS verification requirements apply because the claimed R-value exceeds the default assumption of R-5.8 per inch for closed cell and R-

3.6 per inch for open cell (see Section 6.4).

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Construction Assemblies

6.8.4

Structurally Insulated Panels (SIPs)

6.8.4.1 Inside Finish

Default value gypsum board.

6.8.4.2 Sheathing/Insulation

List the continuous insulation layer on the inside surface (conditioned space side) of the SIP wall.

Options are R1 to R60 insulation.

6.8.4.3 Panel Rated R (@ 75 F)

Specify the panel’s rated R-value at 75 degrees in the cavity path (R14 to R55). In the frame path list the thickness of the panel and whether it is or is not OSB.

6.8.4.4 Sheathing/Insulation

List the continuous insulation layer on the outside surface of the SIP wall. Options are R1 to R60 insulation.

6.8.4.5 Exterior Finish

Exterior finish options are wood siding, 3 coat stucco, or R4 synthetic stucco (also known as 1-coat stucco) and wood siding/sheathing/decking.

6.8.5 Demising and Interior Walls

Walls separating conditioned space from unconditioned space (e.g., from house to garage, knee walls) are modeled in the conditioned space as interior, although actually demising walls. In creating the building envelope, the wall will have conditioned space on one side and unconditioned space or zone on the other side.

When defining multi-family buildings, party walls separating zones are defined as part of both zones in which they occur. The box indicating that there is a dwelling unit on the other side is checked.

When the wall is an interior or demising wall, both the inside and outside surfaces are gypsum board, and there will be no solar gains on the unconditioned side. Knee walls are insulated as a wall.

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Figure 6-9: Interior Walls

Construction Assemblies

6.8.6 Garage

Exterior

Walls

The outermost walls of the garage wall or unconditioned storage space, which are modeled as part of

an unconditioned zone, typically do not have insulation (see Figure 6-10).

Figure 6-10: Uninsulated Exterior Wall

6.9 Floors

Raised floor types that can be created include wood framed , steel framed, and SIPs over a crawl space (with a crawl space zone associated with the building), over exterior (no crawl space), or

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interior floor (which includes a floor over garage (although actually a demising surface)). See Figure

6-11 through Figure 6-13.

Figure 6-11: Floor over crawl space

Figure 6-12: Floor over exterior

6.9.1 Raised Floor Construction Data

6.9.1.1 Construction Name

User-defined name.

6.9.1.2 Can Assign To

This is a fixed field. To create a new assembly type, at the zone level, pick create and make the appropriate construction assembly type.

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6.9.1.3 Construction Type

Options includeDefault is wood and steel frame construction , or SIPs .

Construction Assemblies

6.9.2 Raised Floor Construction Layers (top to bottom)

6.9.2.1 Floor Surface

The available floor surface type s isare carpeted , hardwood, tile, and vinyl .

6.9.2.2 Concrete Fill

Default is no concrete fill. Select no concrete fill, or concrete fill.

6.9.2.3 Floor Deck

Select (1) no floor deck or (2) wood siding, sheathing, decking

6.9.2.4 Cavity/Frame

List the compressed R-value of cavity insulation (see Section 6.1) in the cavity column. The framing

column is to indicate the size of the framing and the spacing (e.g., 2x6 with 16-inch on center framing) or panel size for SIPs .

6.9.2.5 Sheathing/Insulation

List the sheathing or insulation layer on the outside of the framing. Options are none, gypsum board, and R1 to R 1260 insulation.

6.9.2.6 Exterior Finish or Ceiling Below Finish

Optional input. Select either (1) wood siding, or (2) – select finish for exterior floors or gypsum board for an interior floor or floor over garage.

6.9.2.7 Non-Standard Spray Foam in Cavity

This check box identifies additional documentation and HERS verification requirements due a claimed R-value that exceeds the default assumption of R-5.8 per inch for closed cell and R-3.6 per

inch for open cell (see Section 6.4).

6.9.3 Floor Over Garage

A floor over a garage is modeled as an interior floor. When defining the building envelope, the outside surface will be set to garage rather than another conditioned zone. By modeling it as an interior floor, the ceiling below can be set to gypsum board or be left undefined (“- select inside finish –“).

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Figure 6-13: Interior Floor

Construction Assemblies

6.9.4 Window Types

Create a library of window types using product specific values for U-factor and SHGCs. Even if you wish to keep the default values, be sure to retype them. You may notice the text change from blue to red. This ensures the values will not change (if you change to a climate zone with different window requirements). For the greatest flexibility, leave size, overhang or fin fields blank and create values for products with different values, such as operable, fixed, glass block, doors, existing single pane windows, or a specific brand of windows.

If you wish to take advantage of the defaulting system, leave the fields blue (or swipe the cursor across the field, right-click and pick “restore default”). This will change the SHGC value to 0.50 if you pick climate zone 1 , 3 or 165 , or to 0.25 in climate zones 2 , 4, or 6-16-15 .

Figure 6-14: Window Type

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Chapter 7. Building Envelope

Once the conditioned zone is defined (see Figure 7-1) the different components of the building

envelope can be created or modified.

Figure 7-1: Conditioned Zone

7.1 Orientation

The orientation of walls, windows, and any orientation other than front orientation is the plan azimuthorientation or plan view. It is the view looking at the plans (front, left, back, right) or as if standing outside and looking at the front of the building. The numeric value for the plan view of walls and windows is the same for every building—front is 0, left is 90, back is 180, and right is 270.

When defining surfaces use the labels front, left, back and right, and only specify a value when the walls are at an angle, such as a bay or corner wall, in which case you will specify the orientation

“ relative to the front.

If there is a bay off the back of a building (see Figure 7-2) the back angled

walls are entered as 135 and 225. If the bay is off the front, the angled walls are at 315 and 45. The software adjusts these for the energy use and as reported on the CF1R based on the front orientation entered for Building, Front Orientation , and will report the actual azimuth .

NOTE: if you enter the actual orientation of walls, the software models the value entered plus the building front orientation, and the output will not match the proposed building. If you enter the actual orientation of the walls, the only way for the output to be correct would be to define the front orientation as 0 and most plan checkers will not understand why the site plan and your building front do not match.

Additionally, to assist inspectors, the CF1R report was modified to include the side of the building or plan orientation.

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Figure 7-2: Plan AzimuthOrientation

Building Envelope

7.2 Opaque Surfaces

Working from top down, add any ceilings below attic as well as any cathedral ceilings.

7.2.1 Ceiling below attic

7.2.1.1 Name

User-defined name. If the building plans have a unique identifier, that should be used here to assist in the plan checking and inspection processes.

7.2.1.2 Belongs to Zone

Select any appropriate zone already included in the building model. When copying components of one zone to another, this field automatically changes.

7.2.1.3 Construction

If no appropriate construction assembly is available, right-click and pick create (discussed in depth

in Chapter 6, Construction Assemblies).

7.2.1.4 Ceiling Area

Area of the ceiling, in square feet.

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7.2.2 Cathedral Ceiling

The information needed to define a cathedral ceiling is shown in Figure 7-3). Because the orientation

is entered for cathedral ceilings, the ceiling will be modeled in multiple entries, with a typical cathedral ceiling having two or more parts (e.g., left and right).

Figure 7-3: Cathedral Ceiling

7.2.2.1 Ceiling Name

User-defined name. If the building plans have a unique identifier, that should be used here to assist in the plan checking and inspection processes.

7.2.2.2 Belongs to Zone

Select any appropriate zone already included in the building model. When copying components of one zone to another, this field automatically changes.

7.2.2.3 Construction

If no appropriate construction assembly is available, right-click and pick create (discussed in depth

in Chapter 6, Construction Assemblies).

7.2.2.4 Ceiling Area

Area of the ceiling, in square feet.

7.2.2.5 Roof Rise

Specify the roof rise or roof pitch, which is the number of feet the roof rises in a span of 12 feet (e.g., shown on plans as 4:12 or 4 feet in 12 feet). If there are multiple pitches you can enter the roof rise of the largest area of roof

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7.2.2.6 Orientation

The plan view using labels front, left back and right. If specifying a value, it is based on front = 0, left

= 90, back = 180, and right = 270. If the cathedral ceiling is on a part of the building facing an angle,

match the orientation of the walls. See Section 7.1.

7.2.2.7 Solar Reflectance

The default aged solar reflectance is 0.10 for all roof types. Alternatively, enter the aged solar reflectance for a roof product, as published by the Cool Roof Rating Council (CRRC)

(www.coolroofs.org). A higher value is better, so if a specific product color is unknown use a lower value among options to avoid having to regenerate compliance documentation during construction.

See also Section 5.2.1.7.

7.2.2.8 IR Emittance

The default thermal emittance (or emissivity) for all roofing materials is 0.85. Alternatively, enter the emittance value published by the Cool Roof Rating Council (CRRC) (www.coolroofs.org). See also

Section 5.2.1.8.

7.2.3 Knee Walls

Model any knee walls (a sidewall separating conditioned space from attic space under a pitched roof or where ceiling heights change), as an interior wall with the outside surface as attic, with insulation value typical for a wall.

7.2.4 Party Walls in Multi-Family

If each dwelling unit in a multi-family building is modeled as a separate zone, model any interior walls separating one dwelling unit from another as part of both dwelling units. Both zones are identified, as well as checking the box that the zone on the other side is modeled

(see Figure 7-4).

Figure 7-4: Party Wall

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7.2.5 Walls

Add the walls in a clockwise or counter-clockwise direction and in the order you would like them to

appear because it is not possible to change the order. See Figure 7-5.

Figure 7-5: Exterior Wall

7.2.5.1 Exterior Wall Name

If the building plans use a unique tag or ID, use that for the name, otherwise a simple name such as front or front wall is sufficient. Each name within a zone or on a surface must be unique.

7.2.5.2 Belongs to Zone

The name of the zone in which the wall is being modeled.

7.2.5.3 Surface Status

Surface status is used to identify an existing, altered or new wall. Any surfaces that are part of a new building or addition are new.

7.2.5.4 Construction

Pick one of the construction assemblies or create a new construction assembly (see Section 6.8)

7.2.5.5 Wall Area

Gross wall area, in square feet (the area of windows and doors associated with the wall will be subtracted).

7.2.5.6 Wall Tilt

A wall typically has a tilt of 90 degrees but may range from greater than 60 degrees to less than 120

degrees (see Figure 7-6).

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7.2.5.7 Orientation

The plan view orientation. Use front, left, back and right. If specifying a value, it is based on front being equal to 0, left is 90, back is 180, and right is 270, rather than the actual building orientation.

The software will add the front orientation and this plan orientation to determine the actual

orientation of the modeled surface. See Section 7.1.

Figure 7-6: Surface Tilt

Outside Inside

Outside

Inside

Inside

Outside

Walls have a tilt greater than 60 but less than 120 degrees from the horizontal

Roofs have a tilt less than 60 degrees from the horizontal

Floors have a tilt of 180 degrees from the horizontal

7.2.6 Opaque Doors

Figure 7-7: Opaque Door

Doors and windows (fenestration) are modeled separately. For doors with glass, first determine if only part of the door or the entire door is a window. When a door is less than 50 percent glass, calculate the glass area plus two inches on all sides (to account for a frame) and model that as

window (see Section 7.3.1). The opaque area of the door is the total door area minus the calculated

glass area. For doors with 50 percent or more glass area see Section 7.3.4. The standard design

building has the same area of opaque door as the proposed design building.

7.2.6.1 Door Name

User defined name. If the plans use a door schedule or unique identifier, that identifier can be used for the door name. Each surface must have a unique name.

7.2.6.2 Belongs to Exterior Wall

Default is the existing wall. When copying window data to another zone, the program changes this to the new exterior wall.

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7.2.6.3 Door Status

The default is new for new construction or if part of an addition. Other options include altered and existing.

7.2.6.4 Door Area

Enter the door area, in square feet.

7.2.6.5 U-factor

Default value is 0.50 for opaque doors, 1.00 for the large garage doors (roll-up or wood). Other values allowed are from Joint Appendix 4, Table 4.5.1, only.

7.2.7 Garage Door

When modeling a garage zone, the large garage doors (metal roll-up or wood) are modeled with a

1.00 U-factor.

7.3 Windows

The 2013 standards establish a maximum weighted average U-factor of 0.58 (Section 150.0(q)) for fenestration, including skylights. The exception allows the greatest of 10 ft 2 or 0.5 percent of the conditioned floor area to exceed the maximum 0.58 U-factor.

Create a library of window types using either default values or product specific values for U-factor

and SHGCs (see 6.9.4). Since you must model each window individually, this gives you the greatest

flexibility by allowing you to update the window efficiencies with the least amount of effort. When you create a new window type, even if you wish to keep the default values, be sure to retype them so the values on the window type screen are red. Then when you pick the window type the window data screen picks up the values (in blue) from the window type fields.

7.3.1 Windows Data

Right-click on the wall to which you will add windows and pick <create> and select window. The

screen shown in Figure 7-8 is displayed.

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Figure 7-8: Window Data

Building Envelope

7.3.1.1 Window Name

User defined name. If the plans use a window schedule or unique identifier, that identifier can be used for the window name. Each window on a given surface must have a unique name.

7.3.1.2 Belongs to Exterior Wall

Defaults to the wall on which the window was created. When copying window data to another zone, the program changes this to the new exterior wall.

7.3.1.3 Surface Status

Select new, altered or existing.

7.3.1.4 Window Type

If using a window type from the library you created, select from the valid options. This field can also be left as “none.”

7.3.1.5 Specification Method

Select either Window Dimensions (required for fins and overhangs) or Overall Window Area.

7.3.1.6 Model Window Fins and/or Overhangs

Check box is available only when Section 7.3.1.4 is set to window dimensions.

7.3.1.7 Window Area

If using the overall window area, enter the area of a window (in square feet) and the multiplier. For example, if there are three 3 0 5 0 windows, enter window area “15” ft 2 and multiplier “3.”

7.3.1.8 Width

If using the window dimensions method, enter the window width (in feet).

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7.3.1.9 Height

If using the window dimensions method, enter the window height (in feet).

7.3.1.10 Multiplier

The number of identical windows (NOTE: must also have identical overhang and fin conditions, if modeled).

7.3.1.11 NFRC U-factor

U-factor from National Fenestration Rating Council (NFRC) for the window product (not the center of glass value) (www.nfrc.org). Alternatively, enter the default value from standards Section 110.6,

Table 110.6-A.

7.3.1.12 Solar Heat Gain Coefficient

Solar Heat Gain Coefficient (SHGC) from NFRC for the fenestration product (www.nfrc.org).

Alternatively, enter the default value from standards Section 110.6, Table 110.6-B.

7.3.1.13 Source of U-factor/SHGC

The three valid sources are NFRC, default, or Alternate Default Fenestration Procedure (ADFP). A rarely used provision in the standards is for unrated site-built fenestration, which requires use of

Reference Appendix NA6 to calculate both the U-factor and SHGC. Whichever source is used, the standards require a temporary label on every window. See References Appendices (CEC-400-20012-

005), p. NA6-1 through 6-5 for further information and responsibilities associated with this calculation procedure.

7.3.1.14 Exterior Shade

Default bug screens for windows, none for skylights.

7.3.2 Window Overhang

Under the Window Overhang tab (see Figure 7-9) enter the overhang dimensions and position.

7.3.2.1 Depth

Distance the overhang projects out from the wall (in feet).

7.3.2.2 Distance Up

The distance (as viewed from elevations) from the top of the window to the bottom of the overhang

(in feet).

7.3.2.3 Extends Left

Distance (in feet) the overhang extends from the left edge of the window to the end of the overhang.

7.3.2.4 Extends Right

Distance (in feet) the overhang extends from the right edge of the window to the end of the overhang.

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Figure 7-9: Overhang

Building Envelope

7.3.2.5 Flap Height

Default 0 feet. If the overhang has a flap that extends lower than the bottom of the overhang, thereby increasing the potential shading of the overhang, this added length is modeled as the flap height.

7.3.3 Window Fins

A window fin is a building feature that provides shading benefit to a window (for example, a

recessed entry area). Figure 7-10 shows inputs found in the Window Fins tab.

7.3.3.1 Left Fin Depth

Depth (in feet) of the wall (fin) to the left of the window that provides shading to the window.

7.3.3.2 Distance Left

Distance (in feet) from the left edge of the window to the left fin.

7.3.3.3 Top Up

Distance (in feet) from the top of the window to the top of the wall (fin).

7.3.3.4 Bottom Up

Distance (in feet) from the bottom of the window to the bottom of the left fin.

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Figure 7-10: Window Fin

Building Envelope

7.3.3.5 Right Fin Depth

Depth (in feet) of the wall (fin) to the right of the window that provides shading to the window.

7.3.3.6 Distance Right

Distance (in feet) from the right edge of the window to the right fin.

7.3.3.7 Top Up

Distance (in feet) from the top of the window to the top of the wall (fin).

7.3.3.8 Bottom Up

Distance (in feet) from the bottom of the window to the bottom of the right fin.

7.3.4 Glass Doors

For a door with 50 percent or more glass area, or a door with an NFRC rating, the entire door area is modeled as a window.

The glass area (in square feet) of a door with less than 50 percent glass is the sum of all glass surfaces plus two inches on all sides of the glass (to account for a frame). This area is modeled as a window.

The remaining area of the door is modeled as opaque door (see Section 7.2.6).

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7.4 Skylights

To create a skylight, a section of cathedral ceiling with an area slightly larger than the skylight must be created. Right-click on the cathedral ceiling surface and pick <create> and se lect skylight (see

Figure 7-11).

Figure 7-11: Skylight

7.4.1.1 Skylight Name

User defined name. If the plans use a window schedule or unique identifier, that identifier can be used for the window name. Each skylight on a given surface must have a unique name.

7.4.1.2 Belongs to Cathedral Ceiling

Defaults to the cathedral ceiling on which you picked create.

7.4.1.3 Skylight Area

Area of the skylight (in square feet).

7.4.1.4 Skylight Status

Select New, Existing, or Altered.

7.4.1.5 Multiplier

The number of identical skylights.

7.4.1.6 NFRC U-factor

U-factor from National Fenestration Rating Council for the skylight (www.nfrc.org), or default from

Section 110.6, Table 110.6-A.

7.4.1.7 Solar Heat Gain Coefficient

Solar Heat Gain Coefficient (SHGC) from National Fenestration Rating Council for the skylight

(www.nfrc.org), or default from Section 110.6, Table 110.6-B.

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7.4.1.8 Source of U-factor/SHGC

The three valid sources are NFRC, default, or Alternate Default Fenestration Procedure (ADFP). See

Section 7.3.1.13

.

7.5 Raised Floor

When a raised floor is over an unconditioned space, such as a garage, model this as an interior floor.

CBECC recognizes that the outside condition is an unconditioned space. When creating a raised floor over a crawl space, the software will create the associated crawl space zone.

7.5.1 Floor over Crawl Space

Figure 7-12: Raised Floor

7.5.1.1 Exterior Floor Name

User-defined name. If the building plans have a unique identifier, that should be used here to assist in the plan checking and inspection processes.

7.5.1.2 Belongs to Zone

Select any appropriate zone already included in the building model. When copying components of one zone to another, this field automatically changes.

7.5.1.3 Surface Status

Select New, Existing, or Altered.

7.5.1.4 Construction

Raised floor over crawl space, exterior floor, or interior floor. If an appropriate construction assembly

is not available, right-click and pick <create> (discussed in depth in Chapter 6, Construction

Assemblies).

7.5.1.5 Floor Area

Area of the floor, in square feet.

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7.5.1.6 Floor Elevation

Height above grade or depth of crawl space, in feet. For multi-story buildings, this value must match the input “bottom” in modeled in the zone data.

7.5.2 Floor Over Garage

A raised floor over a garage or over another conditioned space is modeled as an interior floor, but with an unconditioned zone on the other side.

Figure 7-13: Garage or Interior Floor

Figure 7-14: Multi-Family Interior Floor

7.5.2.1 Interior Floor Name

User-defined name. If the building plans have a unique identifier, that should be used here to assist in the plan checking and inspection processes.

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7.5.2.2 Belongs to Zone

Select any appropriate zone already included in the building model. When copying components of one zone to another, this field automatically changes.

7.5.2.3 Surface Status

Select New, Existing, or Altered.

7.5.2.4 Construction

Interior raised floor. If an appropriate construction assembly is not available, right-click and pick

create (discussed in depth in Chapter 6, Construction Assemblies).

7.5.2.5 Outside

The outside condition or adjacent zone.

7.5.2.6 Different Dwelling Unit on Other Side

A checkbox(see Figure 7-14) is included when the project is identified as multi-family to indicate

whether another dwelling unit is on the other side of the surface being modeled.

7.5.2.7 Floor Area

Area of the floor, in square feet.

7.5.2.8 Floor Elevation

Height above grade or depth of crawl space, in feet. For multi-story buildings modeled as multiple

zones, this value must be consistent with the value input for “bottom” in zone data (see Figure 7-15).

Figure 7-15: Zone Elevation Height

7.5.3 Floor Over Exterior

This type of floor is only used when there is no crawl space and no unconditioned space underneath the floor. Floors with a garage or unconditioned space underneath are modeled an interior floor

(with the adjacent zone being unconditioned).

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Figure 7-16: Exterior Floor

Building Envelope

7.5.3.1 Exterior Floor Name

User-defined name. If the building plans have a unique identifier, that should be used here to assist in the plan checking and inspection processes.

7.5.3.2 Belongs to Zone

Select any appropriate zone already included in the building model. When copying components of one zone to another, this field automatically changes.

7.5.3.3 Surface Status

Select New, Existing, or Altered.

7.5.3.4 Floor Type

Raised light floor or other floor type available from the drop-down menu.

7.5.3.5 Construction

Raised floor over exterior. If an appropriate construction assembly is not available, right-click and

pick create (discussed in depth in Chapter 6, Construction Assemblies).

7.5.3.6 Floor Area

Area of the floor, in square feet.

7.5.3.7 Floor Elevation

Height above grade or depth of crawl space, in feet. For multi-story buildings modeled as multiple

zones, this value must be consistent with the value input for “bottom” in zone data (see Figure 7-15).

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7.6 Slab Floor

Slab on grade floors are modeled in conditioned spaces, unconditioned spaces, heated slab floors, slab floors with mandatory or optional slab edge insulation, floors with 20% exposed and 80% covered, or some other combination of exposed and covered slab.

Figure 7-17: Slab Floor Data

7.6.1.1 Slab Floor Name

If the building plans use a unique tag or ID, use that for the name. Each name within a zone or on a surface must be unique.

7.6.1.2 Belongs to Zone

The name of the zone in which the slab is being modeled.

7.6.1.3 Slab Floor Status

Select New, Existing, or Altered.

7.6.1.4 Floor Area

Area in square feet measured from the outside of the exterior surface of the zone.

7.6.1.5 Perimeter

Length of slab edge (in feet) between the space modeled and exterior only. Do not include the length of edge that occurs between the house and garage (an area that cannot be insulated if the edge is being insulated).

7.6.1.6 Heated slab

Check box to indicate that the slab is heated, in which case mandatory insulation requirements apply. See Standards Section 110.8.

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7.6.1.7 Surface

Default 20% exposed/80% covered, otherwise specify exposed or covered slab (modeled separately).

Covered slab includes carpet, cabinets, and walls. No building has 100% exposed slab.

7.6.1.8 Slab Has Edge Insulation

Check box to indicate that the slab edge will be insulated.

7.6.1.9 R-value & Depth

When slab edge insulation is indicated in the check box, the R-value and depth of the proposed slab edge insulation is identified. Depth of insulation installed vertically is specified in inches. Depth of insulation installed horizontally is specified in feet.

7.7 Exterior Garage Surfaces

In addition to the surfaces separating the house from the garage (which continue to be modeled as

part of the conditioned zone), model attached unconditioned spaces (see Figure 7-18).

No surface is modeled more than once, so if the garage ceiling is a floor in the conditioned space zone, it is not modeled in the garage zone. The garage surfaces are typically not insulated and it is not necessary to model any windows. Model the area and type of ceiling, slab floor (perimeter length is only to exterior), any walls (typically with R-0 insulation) and the large metal roll-up or wood door

(U-factor 1.00) and the door to outside. In a one-story building, the attic is typically shared with the conditioned space (NOTE: this is why the attic area (which cannot be edited) is bigger than the conditioned space).

The surfaces that separate the house or conditioned zone from the garage are modeled with the

conditioned zone as interior walls and interior floors (see Sections 6.8.3 and 6.9.3).

Figure 7-18: Attached Garage

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Chapter 8. Mechanical Systems

The heating, cooling, duct/distribution system and space conditioning fans are defined at the zone

level (see Section 5.4.1.10). The indoor air quality ventilation and cooling ventilation are defined at

the project level (see Sections 4.6 and 4.7). The details of these systems are contained under the

mechanical tab (see Figure 8-1). The information in this chapter is from the point of view of the

mechanical tab.

Figure 8-1: Mechanical Tab

NOTE: Until an exceptional method is approved for mini-split, multi-split, evaporative cooling, room air conditioners, room heat pumps or ground source heat pumps systems, these systems are modeled as equivalent to a standard design system with no penalty and no credit.

8.1 HVAC System Data

The details of the HVAC system are shown in Figure 8-2.

8.1.1.1 System Name

User-defined name.

8.1.1.2 System Type

Select the correct system type as:

• Heat pump heating and cooling system,

• Variable outdoor air ventilation central heat/cool system for central fan integrated night ventilation cooling - variable speed (for example, NightBreezeSmart Vent ™), or

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• Other heating and cooling system for typical HVAC systems or for central fan integrated night ventilation cooling - fixed speed (for example, SmartVentNight Breeze ™).

Figure 8-2: HVAC System Data

8.1.1.3 Unique Heating Unit Types

Indicate the number of unique system types. Not the same as “count” which is the number of systems.

8.1.1.4 Heating Unit

Name of the heating system, details of which are specified as shown in Section 8.2.

8.1.1.5 Count

Number of specified heating units to be installed.

8.1.1.6 Unique Cooling Unit Types

Indicate the number of unique system types. Not the same as “count” which is the number of systems.

8.1.1.7 Cooling Unit

Name of the cooling system, details of which are specified as shown in Section 8.3 (heat pump

cooling is included with heating in Section 8.2.2).

8.1.1.8 Count

Number of specified cooling units to be installed.

8.1.1.9 Cooling Vent

When displayed for a central fan integrated night ventilation cooling system, select Fixed Flow.

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8.1.1.10 Cool Vent Fan

When displayed for central fan integrated night ventilation cooling, specify the fan that circulates air for cooling ventilation, or create a new fan with CFM and W/CFM details. This system will require

HERS verification.

8.1.1.11 Distribution

Name of the duct or distribution system, details of which are specified as shown in Section 8.4.

8.1.1.12 Fan

Name of the HVAC fan system, details of which are specified as shown in Section 8.5. If using central

fan integrated night ventilation cooling, this is the furnace fan that operates in ventilation mode.

8.1.2 Zonal Control

With zonal control, the sleeping and living areas are modeled separately for space conditioning.

Some of the requirements for this compliance option include each habitable room must have a source of space conditioning, the sleeping and living zones must be separately controlled, a non-closeable opening between the zones cannot exceed 40 ft 2 , each zone must have a temperature sensor and a setback thermostat, and the return air for the zone must be located within the zone. Additionally, zonal control credit is not available if space heating is provided by a heat pump or combined hydronic system. A full list of eligibility criteria for this measure is presented in the Residential

Compliance Manual, Section 4.5.2. Figure 8-3 and Figure 8-4 show where the ability to model zonal

control is activated via a check box and the zone type. See also Sections 8.3.1.5 and 8.4.1.6 for

information about the exception to the 350 CFM requirement for single-speed zoned systems.

Figure 8-3: Zonal Control from Section 4.4.1.8

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Figure 8-4: Type from Section 5.4.1

Mechanical Systems

8.1.3 Multiple HVAC Systems

When multiple systems of the same type serve different areas of a building, it is the user’s option to separately zone the systems. If modeled as one system, use either a weighted average efficiency or the lowest efficiency. For multi-family buildings modeled by floor rather than by dwelling unit, if the equipment efficiencies are different, the software will use the lowest efficiency unit.

When multiple systems of different equipment or fuel types serve the building, each type must be modeled as a separate zone to accommodate the different equipment types.

When multiple systems serve the same floor area, only one system can be modeled. The system modeled depends on the size and types of systems. If the capacity of the secondary system does not exceed 2 kW or 7,000 Btu/hr and is controlled by a time-limiting device of 30 minutes or less, the system is considered supplemental and may be ignored (Residential Compliance Manual, Section 8.7.3, and Section 150.1(c)6). If the system does not meet these criteria, the system that is modeled is the one that consumes the most TDV energy. For spaces with electric resistance heat in addition to another heating system, the electric resistance heat is the system that must be modeled.

8.2 Heating Systems

The heating system is the equipment that supplies heat to an HVAC System. Heating systems are

categorized according to the types show in Table 8-1.

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8.2.1 Heating System Data (other than heat pump)

See Figure 8-5 for the heating system data input screen, which varies slightly by equipment type. Not

all system types are currently implemented.

8.2.1.1 Name

User-defined name for the heating system.

8.2.1.2 Type

Heating system type (see Table 8-1).

8.2.1.3 Efficiency

Enter an appropriate efficiency for the equipment type (e.g., 80.6 AFUE). The software will include the minimum efficiency for typical system types. Efficiency information for a specific model number of heating and cooling equipment is found by performing an “advanced search” in the Energy

Commission’s appliance directories (http://www.appliances.energy.ca.gov/) or from the Air-

Conditioning, Heating, and Refrigeration Institute (AHRI) Certified Products Directory http://www.ahridirectory.org.

For more information on the default efficiency for wall furnaces, floor furnaces, and heaters, see

Section 8.2.6.

Table 8-1: Heating Equipment

Descriptor

Central Furnace

Heater [wall, floor or space heater]

Boiler

Electric

Combined

Hydronic

Heating Equipment Reference

Fuel-fired central furnaces, propane furnaces or heating equipment considered equivalent to a gas-fired central furnace, such as wood stoves that qualify for the wood heat exceptional method. Gas fan-type central furnaces have a minimum AFUE=78%.

Distribution is ducted. [Efficiency metric: AFUE]

Non-central fuel-fired space heaters, such as wall heaters, floor heaters or unit heaters.

Distribution is non-ducted. [Efficiency metric: AFUE]

Gas or oil boiler. Boiler may be specified for dedicated hydronic systems or as part of a combined hydronic system (providing space and water heating). Distribution is nonducted. [Efficiency metric: AFUE]

All electric heating systems (other than heat pumps), including electric resistance, electric boilers and storage electric water heaters. Distribution system is ducted or non-ducted.

[Efficiency metric: HSPF]

Water heating system can be storage gas, storage electric or heat pump water heater.

Distribution systems can be ducted or non-ducted. [Efficiency metric AFUE, Recovery

Efficiency or Thermal Efficiency]

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Figure 8-5: Heating System Data

Mechanical Systems

8.2.2 Heat Pumps

(Air Source)

See Figure 8-6 for heat pump system data input screen, which varies slightly by equipment type.

8.2.2.1 Name

User-defined name for the system.

8.2.2.2 Type

Heat pump system type (see Table 8-2).

8.2.2.3 Heating Performance HSPF

Enter the heating seasonal performance Factor (HSPF). Efficiency information for a specific model number is found by performing an “advanced search” in the Energy Commission’s appliance directories (http://www.appliances.energy.ca.gov/) or from the AHRI Certified Products Directory http://www.ahridirectory.org.

For systems rated with a COP only , which require an HSPF , convert the COP to a Heating Seasonal

Performance Factor (HSPF)

using Equation 8-1.

Equation 8-1: H SPF = (3.2 x COP) – 2.4

8.2.2.4 Capacity @ 47 Degrees F

Required value from the AHRI Certified Products Directory http://www.ahridirectory.org. Capacity is used to determine the energy use of the backup electric resistance heat. In a multi-family building you will indicate the capacity for the defined system and specify the number of units of that given

capacity assigned to the zone (see Section 8.1.1.5).

8.2.2.5 Capacity @ 17 Degrees F

Required value from the AHRI Certified Products Directory http://www.ahridirectory.org.

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8.2.2.6 Cooling Performance - SEER

Cooling equipment Seasonal Energy Efficiency Ratio (SEER). For equipment tested only with an

EER, enter the EER as the SEER. When a value higher than 13 SEER for “Compliance 2014” is modeled, it triggers a HERS Verification of High SEER. With “Compliance 2015” the minimum efficiency requirement of the Appliance Efficiency Standards changes to 14 SEER, and only when an

SEER higher than 14 is modeled is a HERS Verification of High SEER triggered. Efficiency information can be obtained from an advanced search of the Energy Commission’s appliance directories (http://www.appliances.energy.ca.gov/) or from the AHRI Certified Products Directory http://www.ahridirectory.org.

8.2.2.7 EER

Cooling equipment Energy Efficiency Ratio (EER). When an EER value of higher than 11.3 is modeled with “Compliance 2014” or an EER higher than 11.7 is modeled with “Compliance 2015”, it triggers a HERS verification. For equipment with an EER rating only (e.g., room air conditioner), enter the EER as the SEER. Because the EER depends on the specific combination of coil and condenser model numbers, the EER ratings must be obtained from AHRI directory http://www.ahridirectory.org.

8.2.2.8 CFM per Ton

The mandatory requirement for cooling airflow is 350 CFM/ton for ducted cooling systems (also assumed for dwellings with no cooling), or 150 CFM/ton for Zonal Single Speed systems. Users may model a higher airflow. All systems other than no cooling require HERS verified system airflow using diagnostic testing procedures from Reference Appendices, Residential Appendix RA3.

8.2.2.9 AC Charge

Verified refrigerant charge. Select not verified, verified, or Charge Indicator Display (CID). There is no mandatory requirement for verified refrigerant charge, however, the standard design in climate zones 2 and 8-15 includes proper refrigerant charge in the standard design for most equipment types

(see Standards Section 150.1(c)8.).

8.2.2.10 Refrigerant Type

Default R410A assumed for all refrigerant containing equipment.

8.2.2.11 Multi-Speed Compressor

Use this field to indicate if the system is a zonally controlled multi-speed compressor. An exception for single speed compressors would leave this box unchecked and specify 150 CFM/ton (see Section

8.3.1.5).

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Split Heat Pump

Ductless Heat Pump

Package Heat Pump

Large Package Heat Pump

Room Heat Pump

Air to Water Heat Pump

Ground Source Heat Pump

Mechanical Systems

Table 8-2: Heat Pump Equipment

Split heat pump heating system that has one or more outdoor units supply heat to each habitable space in the dwelling unit. Distribution is ducted.

[Efficiency metric: HSPF]

One or more heat pump outdoor units that use refrigerant to transport heat to at least one terminal in each habitable space in the dwelling unit. These include small ductless mini-split and multiple-split heat pumps and packaged terminal (commonly called “through-the-wall”) units

.

Distribution is nonducted. [Efficiency metric: HSPF, COP]

Central packaged heat pump systems. Central packaged heat pumps are heat pumps in which the blower, coils and compressor are contained in a single package, powered by single phase electric current, air cooled, rated below 65,000 Btuh. Distribution system is ducted. [Efficiency metric: HSPF]

Large packaged units rated at or above 65,000 Btu/hr (heating mode).

Distribution system is ducted. These include water source and ground source heat pumps. [Efficiency metric: COP]

A factory encased Same as Ductlesst heat pump that is designed as a unit for mounting in a window, through a wall, or as a consoleexcept that heat is not supplied to each habitable space in the dwelling unit . Distribution is nonducted. [Efficiency metric: COP]

An indoor conditioning coil, a compressor, and a refrigerant-to-water heat exchanger that provides heating and cooling functions. Also able to heat domestic hot water. [Efficiency metric: COP and EER

]

An indoor conditioning coil with air moving means, a compressor, and a refrigerant-to-ground heat exchanger that provides heating, cooling, or heating and cooling functions. Also able to heat domestic hot water.

[Efficiency metric: HSPF, SEER, EER

]

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Figure 8-6: Heat Pump Data

Mechanical Systems

8.2.3

Air to Water Source Heat Pump

See Figure 8-7 for air to water source heat pump input screens.

8.2.3.1 Name

User-defined name for the system.

8.2.3.2 Type

Heat pump system type (see Table 8-2).

8.2.3.3 Heating Performance

Enter the Coefficient of Performance (COP). Efficiency information for a specific model number is found by performing an “advanced search” in the Energy Commission’s appliance directories

(http://www.appliances.energy.ca.gov/) or from the AHRI Certified Products Directory http://www.ahridirectory.org.

8.2.3.4 Capacity @ 47 Degrees F

Required value from the AHRI Certified Products Directory http://www.ahridirectory.org. Capacity is used to determine the energy use of the backup electric resistance heat. In a multi-family building you will indicate the capacity for the defined system and specify the number of units of that given

capacity assigned to the zone (see Section 8.1.1.5).

8.2.3.5 Capacity @ 17 Degrees F

Required value from the AHRI Certified Products Directory http://www.ahridirectory.org.

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8.2.3.6 EER

Cooling equipment Energy Efficiency Ratio (EER).

On the HVAC System Data screen, check the box “System Heats DHW” (see Figure 8-7) and enter

the tank volume, insulation R-value and ambient conditions.

Figure 8-7: Air to Water Source Heat Pump

8.2.4 Ground Source Heat Pump

There is no current method for modeling ground source heat pumps to accurately represent this feature which uses the earth as a source of energy for heating and as a heat sink for energy when cooling. If this system type is being used, the mandatory efficiencies for ground water source heat

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pumps are a minimum Coefficient of Performance (COP) for heating and EER for cooling are entered as well as the capacity. The system is simulated as a standard system . The heating efficiency COP

(from either Energy Commission or AHRI directory (see Section 8.2.1.3) is converted to an HSPF. For

cooling efficiency, the EER may be modeled as the SEER, or the EER may be modeled as both the

SEER and a HERS verified EER.

8.2.5 Hydronic Heating

Whether the heating system is hydronic or combined hydronic, define the system type from the drop down menu as ‘CombHydro’. In the field labeled Combined Hydronic Water Heater, specify the device that is providing the space heating.

Figure 8-8: Hydronic Heating Data

8.2.6 Hydronic Distribution Systems and Terminals

The only combined hydronic systems currently implemented are those that have 10 feet or less of piping in unconditioned space.

When hydronic systems have more than 10 feet of piping (plan view) located in unconditioned space, additional information about the distribution system is needed.

Other information reported includes:

Piping Run Length (ft). The length (plan view) of distribution pipe located in unconditioned space, in feet, between the primary heating/cooling source and the point of distribution.

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Nominal Pipe Size (in.). The nominal (as opposed to true) pipe diameter in inches.

Insulation Thickness (in.). The thickness of the insulation in inches. Enter "none" if the pipe is uninsulated.

• Insulation R-value (hr-ft 2 -

°

F/Btu). The installed R-value of the pipe insulation. Minimum pipe insulation for hydronic systems is as specified in Section 150.1(j).

8.2.7 Wood Heating

When all of the qualifications for the wood heat exceptional method are met (see Residential

Compliance Manual, Section 4.7.7), the heating system (which includes any back-up heating system) receives neither a penalty nor a credit. A hypothetical heating system that meets Package A is modeled. The wood heater and its back-up system are modeled as a 78% AFUE central furnace, with sealed and tested ducts located in the attic with an R-value equivalent to Package A (select “Use all distribution system defaults”).

8.2.8 Electric Heat

Not yet implemented. Electric resistance heat is modeled with a default efficiency of 3.413 an HSPF of 3.413. Electric radiant heat is modeled with an HSPF of 3.55

.

8.2.9 Non-central Heating

Because the minimum appliance efficiency standard for wall furnaces, floor furnaces and heaters is based on size and ranges from an AFUE of 59 to 74, it is important to specify an unachievable efficiency.

For systems such as wall furnaces, floor furnaces, and heaters, where the size of the equipment determines the minimum efficiency, the software will assume 34 Btu/hour per square foot of conditioned floor area in setting the standard design efficiency . If specific details about the proposed heating equipment are unknown, see Residential Compliance Manual, Section 4.2.1 for the minimum standard by type and capacity so that an appropriate efficiency can be modeled . A default assumption of at least 34 Btu/hour per square foot of conditioned floor area can be used to determine an appropriate efficiency.

For the distribution system, model either “none” or a “distribution systems without ducts” as

specified in Section 8.4.1.2.

For systems rated with a Coefficient of Performance (COP) only, convert the COP to a Heating

Seasonal Performance Factor (HSPF) using Equation 8-1 above.

8.3 Cooling Systems

The cooling system is the equipment that supplies cooled air to an HVAC System (see Figure 8-7).

Cooling systems are categorized according to the types shown in Table 8-3. See Table 8-4 for which

measures (some of which are mandatory) require HERS verification.

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Table 8-3: Cooling Equipment

Descriptor

Ductless Split Air

Conditioner

Evaporative Direct

Evaporative

Indirect/Direct

Evaporative Indirect

Cooling Equipment Reference

Split air conditioning outdoor unit that uses refrigerant to transport cooling to at least one terminal in each habitable space in the dwelling unit. These include small ductless mini-split and multiple-split air conditioners and packaged terminal

(“through-the-wall”) units. Distribution is non-ducted. [Efficiency metric: EER]

Direct evaporative cooling systems. Assume minimum efficiency air conditioner.

The default distribution system is ducts in attic. [Efficiency metric: SEER]

Indirect-direct evaporative cooling systems. Assume energy efficiency ratio of 13

EER. Requires air flow and media saturation effectiveness from the Energy

Commission appliance directory. Distribution is ducted or non-ducted. [Efficiency metric: EER]

Indirect cooling systems. The default distribution system is duct in attic; evaporative cooler duct insulation requirements are the same as those for air conditioner ducts.

Assume energy efficiency ratio of 13 EER. Requires air flow and media saturation effectiveness from the Energy Commission directory. [Efficiency metric: EER]

A split mechanical system, with a water-cooled condenser coil. Distribution is ducted. [Efficiency metric: EER]

Evaporatively Cooled

Condenser

Gas Cooling

Large Package Air

Conditioner

No Cooling

Gas absorption cooling. Distribution is ducted. [Efficiency metrics: COP95 (the rated COP for the gas portion), CAP95 (the rated capacity), and PPC (the parasitic electric energy at rated conditions in Watts)]

Systems rated at or above 65,000 Btu/hr (cooling capacity). Distribution is ducted.

[Efficiency metric: EER]

When the proposed building is not cooled or when cooling is optional (to be installed at some future date). Both the standard design and proposed design use the same default system. Distribution is ducted (either the same system as heating

or default ducts in attic). (See also section 8.3.2). [Efficiency metric: SEER]

Package Air Conditioner Central packaged air conditioning systems less than 65,000 Btu/hr cooling capacity.

Distribution is ducted. [Efficiency metric: SEER and EER]

Room Air Conditioner A factory encased Same as Ductless Split air conditioner that is designed as a unit for mounting in a window, through a wall, or as a consoleexcept that heat is not supplied to each habitable space in the dwelling unit . Distribution is non-ducted.

[Efficiency metric: EER]

Split Air Conditioner Split air conditioning systems. Distribution is ducted. [Efficiency metric: SEER and

EER]

8.3.1 Cooling System Data

8.3.1.1 Name

User-defined name for the cooling system.

8.3.1.2 Type

Cooling system type (see Table 8-3).

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Figure 8-9: Cooling System Data

Mechanical Systems

8.3.1.3 SEER

Cooling equipment Seasonal Energy Efficiency Ratio (SEER). For equipment tested only with an

EER, enter the EER as the SEER. When a value higher than 13 SEER for “Compliance 2014” is modeled, it triggers a HERS Verification of High SEER. With “Compliance 2015” the minimum efficiency requirement of the Appliance Efficiency Standards changes to 14 SEER, and only when an

SEER higher than 14 is modeled is a HERS Verification of High SEER triggered. Efficiency information can be obtained from the Energy Commission’s appliance directories

(http://www.appliances.energy.ca.gov/AdvancedSearch.aspx) or from the Air-Conditioning,

Heating, and Refrigeration Institute (AHRI) Certified Products Directory http://www.ahridirectory.org.

8.3.1.4 EER

Cooling equipment Energy Efficiency Ratio (EER). When an EER value higher than 11.3 is modeled with “Compliance 2014” or an EER higher than 11.7 is modeled with “Compliance 2015”, it triggers a

HERS verification. For equipment with an EER rating only (e.g., room air conditioner), enter the EER as the SEER. Because the EER depends on the specific combination of coil and condenser model numbers, the EER ratings must be obtained from AHRI directory http://www.ahridirectory.org.

8.3.1.5 CFM per Ton

The mandatory requirement for cooling airflow is 350 CFM/ton for ducted cooling systems (also assumed for dwellings with no cooling), or 150 CFM/ton for Zonal Single Speed systems. Users may model a higher airflow. All systems other than no cooling require HERS verified system airflow using diagnostic testing procedures from Reference Appendices, Residential Appendix RA3.

8.3.1.6 AC Charge

Verified refrigerant charge. Select not verified, verified, or Charge Indicator Display (CID). There is no mandatory requirement for verified refrigerant charge, however, the standard design in climate zones 2 and 8-15 includes proper refrigerant charge in the standard design for most equipment types

(see Standards Section 150.1(c)8.).

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Charge Indicator Display

System Airflow

Air-handling Unit Fan

Efficacy

EER

SEER

Evaporatively Cooled

Condensers

Table 8-4: Air Conditioning Measures Requiring HERS Verification

Measure

Refrigerant Charge

Description

Air-cooled air conditioners and air-source heat pumps must be diagnostically tested to verify that the system has the correct refrigerant charge.

A Charge Indicator Display (CID), alternative to refrigerant charge testing.

Ducted systems require a verified system airflow greater than or equal to

350 CFM/ton (mandatory requirement) or another specified value.

To verify that fan efficacy is less than or equal to 0.58 Watts/CFM (a mandatory requirement) or other specified criterion.

Credit for higher than minimum EER by installation of specific air conditioner or heat pump models.

Credit for higher than minimum SEER.

Must combine with duct leakage testing, refrigerant charge, and verified

EER.

8.3.1.7 Refrigerant Type

Default R410A assumed for all refrigerant containing equipment.

8.3.1.8 Multi-Speed Compressor

Use this field to indicate if the system is a zonally controlled multi-speed compressor. An exception for single speed compressors would leave this box unchecked and specify 150 CFM/ton (see Section

8.3.1.5).

8.3.2 No Cooling

When no cooling system is installed in a dwelling, create a cooling system using the type NoCooling.

The system is modeled in a way that results in no credit and no penalty. The software sets the default cooling system to a split system air conditioner that exactly meets Package A for the efficiency, airflow, and refrigerant charge. NOTE: The duct system should never be set to none or non-ducted. It is either the same as the heating system ducts (if any), or Package A, whichever is better.

8.3.3

Non-central Cooling

Until the manufacturers of non-typical cooling technologies pursue an exceptional method, the

Energy Commission has determined that there is not enough data about how these systems perform in achieving comfort conditions to simulate their efficiency. Model the proposed system, however, the systems will be modeled as equivalent to the standard design, meaning there is no credit and no

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penalty. Non-ducted systems are modeled with the distribution system defined as a “distribution system without ducts”.

8.3.4 Evaporative Cooling

[Not yet Implemented] Specify one of three types of evaporative cooling: (1) direct evaporative cooler, the most commonly available system type, (2) indirect, or (3) indirect-direct. Product specifications and other modeling details are found in the Energy Commission appliance directory for evaporative cooling. The default system type is evaporative direct, which is assigned an efficiency of 13 SEER (or the minimum appliance efficiency standard for split system cooling). For indirect or indirect-direct, select the appropriate type, based on the Energy Commission appliance directory as well as the air flow and media saturation effectiveness or cooling effectiveness from the

Energy Commission appliance directory, and specify 13 EER (if required input 13 SEER as well).

Direct evaporative coolers are assumed to be equivalent to a minimum split system air conditioner.

The evaporative cooling modeling methodology addresses two performance issues: (1) rising indoor relative humidity during periods with extended cooler operation, and (2) evaporative cooler capacity limitations. Since modeling of indoor air moisture levels is beyond the capability of simulation models, a simplified algorithm is used to prohibit evaporative cooler operation during load hours when operation is expected to contribute to uncomfortable indoor conditions. The algorithm disallows cooler operation when outdoor wet bulb temperatures are 70°F, or above. As for the capacity limitations, since evaporative coolers are 100 percent outdoor air systems, their capacity is limited by the outdoor wet bulb temperature. Each hour with calculated cooling load, the algorithm will verify that the cooling capacity is greater than the calculated house cooling load.

8.4 Distribution System Data

When multiple distribution system details occur within a given zone, each system and the conditioned space it serves may be modeled in detail separately or the systems may be modeled as one large system. When modeled as one system, assume the worst case conditions.

When modeling a multi-story building, the computer model already assumes that some ductwork is between floors and inside the conditioned space.

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Figure 8-10: Distribution System Data

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8.4.1.1 Name

User-defined name.

8.4.1.2 Type

Indicate the type of duct system, location, or no ducts (see Table 8-5).

Table 8-6 summarizes the duct conditions that require HERS verification, including sealed and tested

ducts, which are a mandatory requirement.

Proposed HVAC systems with ducts in the crawl space or a basement must have supply registers within two feet of the floor and show the appropriate locations for the ducts. Ducts in crawl space and basement can be verified by the local enforcement agency (no HERS verification or duct design).

8.4.1.3 Use all distribution system defaults

By checking this option, the detailed information about the supply and return ducts is completed based on other building inputs, including climate zone. NOTE: If you change the climate zone to one with a different Package A duct insulation value, the program will change to match Package A, which may not match the plans.

Figure 8-11: Duct Leakage

8.4.1.4 Duct Leakage

Selected sealed and tested. To specify a target leakage number, select Low Leakage Air Handler (see

Figure 8-10 . HERS verification is required for this mandatory measure.

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8.4.1.5 Duct Insulation R-value

Specify the R-value of HVAC system ducts. The mandatory minimum R-value allowed is 6 . Valid options are 0, 2.1, 4.2, 6.0, 8.0, 10.0 and 12.0

.

Table 8-5: Distribution Type

Descriptor

Ducts located in unconditioned attic

Distribution Type and Location

Ducts located overhead in the unconditioned attic space (and default condition for no cooling).

Ducts located in a crawl space Ducts located in an unconditioned crawl space.

Ducts located in a garage Ducts located in an unconditioned garage space.

Ducts located within the conditioned space (except 12 lineal feet)

Ducts located entirely in conditioned space

Less than 12 linear feet of duct is outside of the conditioned space.

Distribution system without ducts

HVAC equipment and all HVAC ducts (supply and return), furnace cabinet and plenums, located within the conditioned floor space. Location of ducts in conditioned space eliminates conduction losses but does not change losses due to leakage.

Leakage from either ducts that are not tested for leakage or from sealed ducts is modeled as leakage to outside the conditioned space.

Air distribution systems without ducts such as ductless split system air conditioners and heat pumps, window air conditioners, through-the-wall heat pumps, wall furnaces, floor furnaces, radiant electric panels or combined hydronic heating equipment.

Ducts located in exposed locations outdoors. Ducts located in outdoor locations

Verified low-leakage ducts entirely in conditioned space

Verified Low Leakage Ducts in Conditioned Space - defined as duct systems for which air leakage to outside conditions is equal to or less than 25 CFM when measured in accordance with Reference Appendices, Residential Appendix RA3.1.

Ducts located in multiple places

Allows a different location for supply and return ducts.

8.4.1.6 Has Bypass Duct

If the system meets zonal control criteria, indicate if the system has or does not have a bypass duct.

When specifying that there is no bypass duct, this credit requires HERS rater verification with

Reference Appendices, Residential Appendix RA3.1.4.6.

8.4.1.7 Supply Ducts

If Section 8.4.1.3 is unchecked so that credit may be obtained for a verified duct design/reduced

surface area (see Reference Appendices, Residential Appendix RA3.1), enter the supply duct details for area, diameter and location. The supply duct begins at the exit from the furnace or air handler cabinet.

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The supply duct surface area for crawl space and basement applies only to buildings or zones with all supply ducts installed in the crawl space or basement. If the supply duct is installed in locations other than crawl space or basement, the default supply duct location is “Other.” Do not include the surface area of supply ducts completely inside conditioned space, or ducts in floor cavities or vertical chases when surrounded by conditioned space with draft stops.

The surface area of each supply duct system segment is calculated based on its inside dimensions and length. The total supply surface area in each unconditioned location (attic, attic with radiant barrier, crawl space, basement, other) is the sum of the area of all duct segments in that location.

Table 8-6: Summary of Verified Air Distribution Systems

Measure

Duct Sealing

Supply Duct Location, Reduced

Surface Area and R-value

Low Leakage Ducts in

Conditioned Space

Low Leakage Air-handling Units

Return Duct Design

Air Filter Device Design

Bypass Duct Condition

Description

Mandatory measures require that space conditioning ducts be sealed. Field verification and diagnostic testing is required.

Compliance credit for improved supply duct location, reduced surface area and R-value. Field verification that duct system was installed according to the duct design, including location, size and length of ducts, duct insulation R-value and installation of buried ducts. For buried ducts, this measure also requires improved construction quality or QII and duct sealing.

When space conditioning ducts are located entirely in directly conditioned space, this is verified by diagnostic testing. Compliance credit can be taken for verified duct systems with low air leakage to the outside. Field Verification for ducts in conditioned space and duct sealing are required (Reference Appendices, Residential

Appendix RA3.1.4.3.8).

Compliance credit can be taken for installation of a factory sealed air handling unit tested by the manufacturer and certified to the

Commission to have met the requirements for a Low Leakage Air-

Handling Unit achieved. Field verification of the air handler’s model number is required. Duct sealing is required.

Verification to confirm that the return duct design conforms to the criteria given in Table 150.0-C or Table 150.0-D. as an alternative to meeting 0.58 W/CFM fan efficacy of Section 150.0(m)12.

Verification to confirm that the air filter devices conform to the requirements given in Section 150.0(m)12.

Verification to determine if system is zonally controlled, and confirm that bypass ducts condition modeled matches installation.

8.4.1.8 Return Ducts

Return duct surface area is not a compliance variable. If Section 8.4.1.3 is unchecked in order to take

credit for a verified duct design, enter the return duct details for area, diameter and location. The calculations assume that the return duct is located entirely in the attic, unless (a) the return duct is located entirely in the basement, in which case the calculation shall assume basement conditions for the return duct efficiency calculation, or (b) the return duct is located entirely in conditioned space and the system meets the requirements for Verified Low Leakage Ducts in Conditioned Space, in which case the return duct is assumed to be in conditioned space.

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Mechanical Systems

8.4.2 Low Leakage Air Handlers

Credit can be taken for installation of a factory sealed air handling unit tested by the manufacturer and certified to the Energy Commission to meet the requirements for a Low Leakage Air-Handler.

Field verification of the air handler’s model number is required.

A Low Leakage Air Handler is reported on the compliance report and field verified in accordance with the procedures specified in Reference Appendices, Residential Appendix RA3.1.4.3.9.

8.4.3 Verified Low Leakage Ducts in Conditioned Space

For ducted systems the user may specify that all ducts are entirely in conditioned space and the software will model the duct system with no leakage and no conduction losses.

Systems that have all ducts entirely in conditioned space are reported on the compliance documents and this is verified by measurements showing duct leakage to outside conditions is equal to or less than 25 CFM when measured in accordance with Reference Appendices, Residential Appendix RA3.

8.4.4 Buried Ducts

Ducts partly or completely buried under blown attic insulation also meeting the requirements for verified quality insulation installation , verified duct design and duct leakage testing may take credit for increased effective duct insulation using the HERS verified credit for buried ducts. Additional details regarding the duct design and the inspection process can be found in Reference Appendices,

Residential Appendix RA3.1.4 and the Residential Compliance Manual Section 4.4.3

.

The duct design shall identify the segments of the duct that meet the requirements for being buried ducts on the ceiling (“buried ducts”) and ducts that are enclosed in a lowered ceiling and completely covered by ceiling insulation (“deeply buried ducts”) , and these are input separately from supply and return ducts that are not buried . Ducts to be bB uried ducts shall have a minimum of R4.26.0

duct insulation prior to being buried. The ceiling must be level with at least 6 inches of space between the outer jacket of the installed duct and the roof sheathing above.

8.4.4.1 Buried Ducts

Select the check box for buried ducts (see Figure 8-11) and enter the return duct length (in feet) for

the portion of duct runs directly on or within 3.5 inches of the ceiling gypsum board and surrounded with blown attic insulation of R-30 or greater . Determine the appropriate effective R-value may take credit for increased effective duct insulation

as shown in Table 8-7 (assume the worst case where

multiple conditions exist) .

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Mechanical Systems

8.4.4.2 Deeply Buried Ducts

Select the check box for deeply buried ducts (see Figure 8-11) and enter the return duct length (in

feet) for ducts installed in Duct segments deeply buried in lowered areas of ceiling and covered by at least 3.5 inches of insulation above the top of the duct insulation jacket . may claim effective insulation ofModel R-25 duct R-value for fiberglass ceiling insulation and R-31 duct R-value for cellulose ceiling insulation.

Figure 8-12: Buried Ducts

R-43

R-49

R-60

R-30

R-38

Attic Insulation

R-30

R-38

R-40

R-40

R-43

R-49

R-60

Table 8-7: Buried Duct Effective R-values

Nominal Round Duct Diameter

4'' 5'' 6'' 7'' 8''

Effective Duct Insulation R-value for Blown Fiberglass Insulation

R-13 R-13 R-13 R-9 R-9

R-25

R-25

R-25

R-25

R-25

R-25

R-13

R-25

R-13

R-13

R-25

R-25

R-25

R-25

R-25

R-25

R-25

R-25

R-25

R-25

R-25

R-25

R-25

R-25

R-25

Effective Duct Insulation R-value for Blown Cellulose Insulation

R-9 R-4.2 R-4.2 R-4.2 R-4.2

R-15 R-15 R-9 R-9 R-4.2

R-15

R-15

R-31

R-31

R-15

R-15

R-31

R-31

R-15

R-15

R-15

R-31

R-9

R-15

R-15

R-31

R-9

R-9

R-15

R-31

10''

R-4.2

R-4.2

R-4.2

R-4.2

R-9

R-15

R-4.2

R-9

R-13

R-13

R-25

R-25

12''

R-4.2

R-9

R-9

R-9

R-13

R-25

R-4.2

R-4.2

R-4.2

R-4.2

R-9

R-15

R-9

R-13

R-25

R-4.2

R-4.2

14''

R-4.2

R-4.2

R-9

R-4.2

R-4.2

R-4.2

R-9

R-4.2

R-9

R-13

R-4.2

R-4.2

16''

R-4.2

R-4.2

R-4.2

R-4.2

R-4.2

R-4.2

R-9

8.5 HVAC Fan System

The HVAC fan system moves air for the air conditioning and heating systems.

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CBECC User Manual

Figure 8-13: HVAC Fan

Mechanical Systems

8.5.1.1 Name

User-defined name.

8.5.1.2 Type

Default single speed furnace fan.

8.5.1.3 Watts/CFM Cooling

The mandatory requirement in Section 150.0(m)13 is for an air-handling unit fan efficacy less than or equal to 0.58 Watts/CFM as verified by a HERS rater. The alternative to HERS verification of 0.58

Watts/CFM is HERS verification of a return duct design that conforms to the specification given in

Table 150.0-C or D. However, if a value less than 0.58 Watts/CFM is modeled for compliance credit, the fan efficacy value must be verified and the alternative is not allowed.

If no cooling system is installed, this value is assumed to be 0.58 W/CFM.

8.6 Indoor Air Quality (IAQ) Fan Data

Figure 8-14: IAQ Fan Data

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Mechanical Systems

Mechanical ventilation is required to meet minimum indoor air quality (IAQ) requirements of

ASHRAE Standard 62.2 (see Residential Compliance Manual, Section 4.6). The IAQ system requires

HERS verification meeting Reference Appendices, Residential Appendix RA3.3.

The simplest IAQ fan system is an exhaust fan, such as a bathroom fan that meets the criteria in

ASHRAE Standard 62.2 for air delivery and low noise, and that operates continuously. More advanced IAQ fan systems have a supply or both supply and exhaust fans. In most cases, the energy impact of this mandatory requirement is neutral. The only system for which credit can accrue is a central fan integrated system with HERS verified W/CFM of less than 0.58.

8.6.1.1 Name

User-defined name (must be the same name as specified in Section 4.6).

8.6.1.2 IAQ CFM

Enter the size of fan being installed to meet the minimum CFM required to meet the mandatory

ventilation requirements (found under Building in Section 4.4).

8.6.1.3 W/CFM IAQ Vent

The default value is 0.25 W/CFM. The standard design is set to the same value as proposed up to 1.2

W/CFM).

8.6.1.4 IAQ Fan Type

Select exhaust, supply, or balanced (both exhaust and supply).

8.6.1.5 IAQ Recovery Effectiveness

When the fan type is balanced, enter the IAQ Recovery Effectiveness.

8.7 Cooling Ventilation Fans

Ventilation cooling systems bring in outside air to cool the house when this can reduce cooling loads and save cooling energy. Whole house fans involve window operation and attic venting. Central fan integrated systems use the HVAC duct system to distribute ventilation air. Ventilation cooling systems that exhaust air through the attic require a minimum of 1 ft 2 of free attic ventilation area per

1000 CFM of rated capacity for relief (see Section 150.1(c)12 of the standards).

CBECC-Res can model system types shown in Table 4-2. If a “default prescriptive whole house fan” was specified in Section 4.7, there is no need to provide details about the fan. For central fan

integrated (CFI) night ventilation, first make sure that the Cool Vent tab at the project level is set to

CFI (see Section 4.7.1.1). For a fixed speed fan, set the HVAC system type to “Other Heating and

Cooling System” or for a variable speed fan, set the HVAC system type to “Variable Outdoor Air

Ventilation Central Heat/Cool System (see Section 8.1.1.2). Fixed Flow for the Cooling Vent drop-

down menu. It is also necessary that the Cool Vent tab at the project level be set to CFI (see Section

4.7.1.1).

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CBECC User Manual

Figure 8-15: Cooling Ventilation

Mechanical Systems

8.7.1.1 Name

User defined name, which must also be specified in Section 4.7.

8.7.1.2 Use all fan system defaults

Sets the default minimum to 2 CFM/ft 2 .

8.7.1.3 Cooling Vent CFM

If system default is not checked, enter the actual CFM of the proposed ventilation fan.

8.7.1.4 W/CFM Cooling Vent

Enter the Watts/CFM of the proposed system.

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Domestic Hot Water

Chapter 9. Domestic Hot Water (DHW)

The water heating system is defined at the zone level (see Section 5.4.1.11), while the details of the

systems are contained under the mechanical tab. The information in this chapter is from the point of view of the mechanical tab.

9.1 Efficiency Information

Water heaters are required to be certified to the Energy Commission and the applicable efficiency values needed for modeling are found in the on-line certified appliance directory

(http://www.appliances.energy.ca.gov/). From this site, an advanced search yields the most useful information, which can be exported to a spreadsheet format for sorting and searching.

Alternatively, data may be found in the Air-Conditioning, Heating and Refrigeration Institute

(http://www.ahridirectory.org/ahridirectory). The AHRI directory does not contain the standby loss for large water heaters, which is a required input.

The federal minimum efficiency used to establish the standard design changes in 2015. When natural gas is used, the efficiency for small gas storage changes from an energy factor of 0.575 in 2014 to 0.60 in 2015. If the standard design is based on electric, the minimum energy factor for small electric storage changes from 0.904 in 2014 to 0.945 in 2015.

9.2 Water Heater Types

Tank types are based on the Appliance Efficiency Regulations definitions:

• Small storage has an input of less than or equal to 75,000 Btu gas/propane, less than or equal to 105,000 Btu/hr oil, less than or equal to 12 kW electric, or less than or equal to 24 amps heat pump.

• Small tankless has an input of less than or equal to 200,000 Btu per gas/propane, 210,000 Btu per hour or less oil-fired, or 12 kW or less electric. A tankless water heater is a water heater with an input rating of at least 4,000 Btu per hour per gallon of stored water.

• Large storage has an input greater than 75,000 Btu/hr gas or propane, greater than 105,000

Btu/hr oil-fired, or greater than 12 kW electric. Rated with thermal efficiency and standby loss.

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• Large tankless has an input of greater than 200,000 Btu per hour gas/propane, greater than

210,000 Btu per hour oil-fired, or greater than 12 kW electric. Tankless water heater is a water heater with an input rating of at least 4,000 Btu per hour per gallon of stored water.

• Boiler is a space heater supplying steam or hot water for space heating.

• Indirect is a water heater consisting of a storage tank with no heating elements or combustion devices, connected via piping and recirculating pump to a heat source consisting of a boiler.

9.3 Distribution Types

9.3.1 Single Family Distribution Type

Distribution types (Figure 9-1) range from standard (distribution system multiplier 1.0) to

recirculating with no control (distribution system multiplier 7.0) as options with no HERS verification requirement. Some systems are allow for a higher credit if the system will be verified by

a HERS rater. See Table 9-1 for a comparison of the multiplier (lower number equals more efficient

system). More information about distribution types can be found in Residential Compliance Manual,

Section 5.3 and Reference Appendices, Residential Appendix RA3.6.

Figure 9-1: Single Family Distribution Systems

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Domestic Hot Water

Table 9-1: Water Heater Distribution System Multipliers

Distribution System

NO HERS INSPECTION REQUIRED

Standard

Pipe Insulation, All Lines

Insulated and Protected Pipe Below Grade

Parallel Piping

Recirculation, Non-demand Control (no control, runs 24 hrs/day)

Recirculation, Manual Demand Control Push Button

Recirculation, Demand Control Occupancy/Motion

OPTIONAL CASES: HERS INSPECTION REQUIRED

Pipe Insulation, All Lines

Parallel Piping

Compact Design

Point of Use

Recirculation, Demand Control Push Button

Recirculation, Demand Control Occupancy/Motion

Point of Use

Compact Distribution System

Non-Compliant Installation Distribution Multiplier

Distribution System

Multiplier

1.00

0.90

1.40

1.05

7.00

1.15

1.30

0.80

0.95

0.70

0.30

1.05

1.20

0.30

0.70

1.20

9.3.2 Multi-Family Distribution Type

When using central water heating in a multi-family building, the options for distribution systems are

shown in Figure 9-2. More information about distribution types can be found in Residential

Compliance Manual, Section 5.3 and Reference Appendices, Residential Appendix RA3.6.

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CBECC User Manual

Figure 9-2: Multi-Family Distribution Systems

Domestic Hot Water

9.4 Water Heating System Data

Under the Mechanical Tab, the water heating system details are defined (see Figure 9-2).

9.4.1.1 System Name

User defined name. This is the same name that was provided under the Zone Data tab (see Section

5.4.1.11).

9.4.1.2 Distribution type

Drop-down menu with options based on the building and water heater type being specified. See

Section 9.3 and Table 9-1. For installation and compliance requirements see Residential Compliance

Manual Chapter 5 and Reference Appendices, Residential Appendix RA3.6 and 4.4.

9.4.1.3 Multi-Family Hot Water Distribution Type

Drop-down menu with options for the level of control on the recirculating system serving the

dwelling unit, based on the building and water heater type being specified. See Section 9.3.2 and

Figure 9-2. An input for the recirculation loops is also required (see Figure 9-3).

9.4.1.4 Recirculation Pump Power (bhp)

Multi-family recirculation pump power (brakehorse power). Typical value less than 1.00.

9.4.1.5 Efficiency (fraction)

Multi-family recirculation motor efficiency (fraction). Typical value less than 1.00. See

Table 9-2

for

default efficiencies.

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Domestic Hot Water

Table 9-2: Default Recirculating Pump Motor Efficiency

Nameplate or Brake

Horsepower

0.050 (1/20)

0.083 (1/12)

0.125 (1/8)

0.167 (1/6)

0.250 (1/4)

Standard Fan Motor

Efficiency

0.40

0.49

0.55

0.60

0.64

0.333 (1/3)

0.500 (1/2)

0.66

0.70

0.750 (3/4) 0.72

Source: Reference Appendices, Nonresidential Appendix NA3

9.4.1.6 Water Heater(s)

The name of the water heater (which holds more information about the water heater, see Section

5.4.1.11).

9.4.1.7 Count

The number of water heaters named in the adjacent field that are in the system. Include different water heaters or different water heater efficiencies on a different line.

Figure 9-3: Recirculation Loops

9.5 Solar Water Heating Data

When a water heating system has a solar system to provide part of the water heating, the Solar

Fraction (SF) is determined using an F-chart program, OG-100 or OG-300 calculation method (see www.gosolarcalifornia.org). The calculation methods require varying levels of detail about the solar system and the site of the installation. Calculations use published efficiency data for the solar water heating system.

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CBECC User Manual

Figure 9-4: Solar Water Heating Data, Annual

Domestic Hot Water

Figure 9-5: Solar Water Heating Data, Monthly

9.5.1.1 Solar Fraction Type

Select annual or monthly, based on the appropriate calculation method for the system type. See www.gosolarcalifornia.org.

9.5.1.2 Solar Fraction

Enter one annual solar fraction (see Figure 9-4) or 12 monthly solar fractions (see Figure 9-5), as

calculated for the system type.

9.6 Water Heater Data

The specifications of the water heater accessed in Figure 9-3 are contained in the water heater data as

shown in Figure 9-6. The fields will vary based on the tank type.

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Figure 9-6: Water Heater Data Small Storage

Domestic Hot Water

Figure 9-7: Large Storage Water Heater Data

9.6.1.1 Name

User-defined name that is specified in the water heating system data for the field water heater (see

Section 9.4.1.6).

9.6.1.2 Heater Element Type

Choose electric resistance, natural gas, propane, heat pump, or oil.

9.6.1.3 Tank Type

Choose boiler, indirect, large instantaneous, large storage, small instantaneous, small storage, or

unfired tank. Most instantaneous water heaters are small, based on the rated input (see Section 9.2

Water Heater Types).

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Domestic Hot Water

9.6.1.4 Efficiency

Certified efficiency from one of the sources listed in Section 9.1. Based on the tank type, the efficiency

is energy factor for small storage, small instantaneous, and small heat pump water heaters. For large storage, large instantaneous, large heat pump, or boilers the efficiency is thermal efficiency, recovery efficiency, or AFUE . Indirect water heater efficiency is based on the type of device being used to heat the water . Value entered as a decimal, such as 0.60 or 0.80.

9.6.1.5 Standby Loss Fraction

Required input for large storage water heaters and mini tanks . For large storage, a standby loss of 3% is entered as 0.03. For mini tanks, enter the standby loss Watts. Find the standby loss by conducting an advanced search in the Energy Commission’s appliance efficiency database of water heating

equipment (see Section 9.1

)

.

Some large storage water heaters are not required to report standby loss. This value can be calculated using equations from the 2012 Appliance Efficiency Regulations, Tables F2 and F3, as follows:

Standby loss Btu/hr = (rated input / 800) + (110 x (volume x 0.5)

Convert to Standby Loss Percent as:

Standby loss Btu/hr / (8.25 x Volume x 70)

9.6.1.6 Tank Volume

Enter the tank volume (in gallons). The rated input rather than the tank volume is used to determine

if a tank type is large or small (see Section 9.2)

9.6.1.7 Exterior R-value

For indirect and unfired tanks.

9.6.1.8 Input Rating

The input rating (consistent with the tank type) from one of the listed sources in Section 9.1.

9.6.1.9 Ambient Conditions

For an indirect water heater, specify whether it is installed in unconditioned or conditioned space.

9.6.1.10 Recovery Efficiency

If the equipment is part of a hydronic system, enter the recovery efficiency, thermal efficiency or

AFUE for appropriate water heating type. The value comes from one of the listed sources in Section

9.1 and is entered as a percent (e.g., 78, 80).

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CBECC User Manual

Additions and Alterations

Chapter 10. Additions and Alterations

CBECC-Res can model addition alone, alteration alone, or existing plus addition/alteration. For alteration alone, the performance compliance approach can only be used if two or more components are altered. These components include the building’s envelope insulation, fenestration, space conditioning (HVAC) equipment, duct system, water heating system, or roofing products.

Select the run scope on the Analysis tab (see Figure 10-1).

10.1 Addition Alone

To model an addition alone, (1) set the run scope to newly constructed, (2) check the box for

Addition Alone, and (3) set the fraction of the dwelling unit that the addition represents (for example, a 500 ft 2 additon to a 1500 ft 2 house = 500/(1500+500) = 0.25.

Figure 10-1: Run Scope

10.2 Setting the Standard Design

The standard design against which alterations are compared will depend on whether (1) the existing conditions were verified by a HERS rater prior to creating the building model, and (2) the proposed alteration meets or exceeds a minimum efficiency threshold (which may be mandatory or prescriptive).

10.2.1 Third Party Verification

The standard design (energy budget) is not based on the vintage of the building, Instead, existing conditions are either set to actual conditions verified by a HERS Rater or default conditions for alterations meeting prescriptive requirements (see Building Energy Efficiency Standards, Section 150.2,

Table 150.2-B).

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Additions and Alterations

For example, if windows that are single-pane, metal frame, with clear glass are replaced with dualpane, wood frame, Low-E windows, the standard design without verification is based on the existing windows having a 0.40 U-factor and 0.35 SHGC (or 0.66 in zones with no SHGC requirement) . If verified by a HERS rater, the standard design is set using the actual efficiency of the existing windows, which is 1.28 U-factor and 0.80 SHGC.

10.2.2 Efficiency Threshold

Another factor in determining the amount of credit that is achieved by an alteration is the proposed efficiency of the alteration. If an altered component does not meet the mandatory or prescriptive requirement set out in Section 150.2, the standard design will be based on the higher level. For example, if a ceiling has a verified insulation level of R-11, but the proposed alteration is to achieve

R-19, the standard design is based on the standards’ requirement of R-30, and the proposed ceiling insulation alteration will receive an energy penalty.

If more information is needed, the Reference Manual (Residential Alternative Calculation Method

Reference Manual, P400-2013-003-SD), Section 2.11, contains detailed explanations of how each feature of the addition/alteration affects the standard design.

10.3 Existing Building

If the existing building will be modeled as part of an existing plus addition/alteration analysis, the user has the option of specifying the status of a component as existing, altered, or new. Deleted or

removed surfaces are not modeled. Specify the characteristics of all existing , altered or new components (for example, a new window in an existing wall) associated with the existing part of the

building. For altered components see Section 10.3.

If an existing garage is being converted to conditioned space, do not model the unconditioned garage.

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CBECC User Manual

Figure 10-2: Existing Surface

Additions and Alterations

10.4 Addition

The addition is modeled as a separate zone, identified by the Zone Status as new. Set the surface status to “new” for all envelope components in the addition including existing components in a previously unconditioned space., including The exception is an existing HVAC system is being

extended for the addition (see Section 10.4.2 for an explanation of

how to model various scenarios). It is not necessary to define a DHW system in either the existing or new zone, unless one is being altered or added.

Figure 10-3: Addition HVAC and DHW

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Additions and Alterations

10.5 Addition/Alteration

Model any components that will be altered with the surface status “altered” and the new characteristics. You will only specify the existing characteristics if the existing conditions were

verified by a HERS rater (see Figure 10-4 and Figure 10-5). The “verified” check box opens additional

fields to define the existing conditions and affect the standard design (see Section 10.1). If one

component is verified, all components must be verified.

Since only one surface status can be used, separately model components that are being altered from those that will not be altered.

NOTE: Deleted or removed surfaces are not modeled.

Figure 10-4: Altered with Verified Existing Conditions

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Additions and Alterations

Figure 10-5: Altered Without Verified Existing Conditions

10.5.1 Radiant Barrier

Current software limitations do not allow modeling multiple radiant barrier conditions, such as a radiant barrier in an addition but not in the existing attic. radiant barrier that is only in an addition as part of an existing plus addition analysis. What can be modeled is a radiant barrier in an addition alone, or if an entire attic is being altered to include radiant barrier.

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CBECC User Manual

Figure 10-6: Altered HVAC and DHW

Additions and Alterations

10.5.2 HVAC

First determine if an existing system will be extended to serve an addition, if a replacement system

(including ducts) will be installed for the whole house, or if a supplemental system will be added for the addition only. Existing equipment does not need to meet current standards (Exception 4 to

Section 150.2(a)).

Existing equipment to serve addition. For the existing and new zone s , set the system status to

“existing” and model the actual values for the existing system and ducts (the standard and proposed

design will both have the same equipment) (Figure 10-7).

For the addition zone, define a separate system with the system status also “existing,” but with prescriptive default system values (use an

EER value of less than 11.3, such as 11.25, so that a HERS verified EER is not triggered). The distribution system data will have both existing and new parts of the system defined

(Figure 10-8).

Set the duct status to “new” and specify the actual proposed conditions.

Replacement system for whole house. For the existing and new zone s , set the system status to

“altered” and model the proposed system conditions for equipment and ducts (if verified, specify the existing conditions as verified by the HERS Rater). Model the appropriate conditions for the ducts, which may be new (if existing ducts are being replaced) or existing + new. For the addition zone, define a separate system with the system status “new” with same proposed conditions for equipment and ducts.

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CBECC User Manual

Figure 10-7: Existing System Existing Zone

Additions and Alterations

Figure 10-8: Existing System Addition ZoneDuct System

Adding a separate system for the addition. For the existing zone, set the system status to “existing” and model the actual values for the existing system and ducts. For the addition zone, define a separate system with the system status “new” with the proposed conditions of the new supplemental system and duct conditions.

10.5.3 Water heating

If altering a water heater, define the altered specifications. If existing conditions were verified, check the box and include the specifications of the existing equipment. If the distribution system is being altered, and the existing conditions are verified, set the dwelling unit distribution type to “non-

compliant installation distribution multiplier” or other appropriate value (see Section 9.3).

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CBECC User Manual

Additions and Alterations

If adding a water heater, define both the existing water heater in the existing zone, and the added water heater in the addition zone.

10.5.4 Mechanical Ventilation

Alterations and additions of 1,000 square feet or less are not required to meet the mechanical ventilation requirements of Section 150.0(o).

10.5.5 Ventilation Cooling/Whole House Fan

Alterations and additions of 1,000 square feet or less are not required to meet the requirements of

150.1(c)12, which is part of the standard design in climate zones 8-14. If the new conditioned floor area does not exceed 1,000 square feet, there will be no energy penalty for not installing a whole house fan or other ventilation cooling device.

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CBECC User Manual

INDEX

2013 standards effective date ............................ 1-1

ACH50 .................................................................. 4-5

Addition alone .................................................. 10-1

Addition/alteration ........................................... 10-1

Alteration .................................................. 10-4

Deleted surfaces ...................................... 10-4

Existing building ....................................... 10-2

Existing HVAC ......................................... 10-6

HVAC ....................................................... 10-6

Radiant Barrier ......................................... 10-5

Replacing HVAC ...................................... 10-6

Standard Design ...................................... 10-1

Verified by a HERS Rater ........................ 10-1 water heating ........................................... 10-7

Water heating........................................... 10-3

Aggregate ballasted roof default ................................. 5-4 built up roof default .................................... 5-4

Air leakage ........................................................... 4-5

Alteration alone................................................. 10-1

Appliance directory ............................................ 9-1

Attached garage .................................................. 4-7

Attic ............................................................... 5-1, 6-3 area ............................................................ 5-3 conditioned ................................................. 5-2 radiant barrier ............................................. 6-4 venting ........................................................ 5-2

Attic roof terminology........................................ 6-3

Bedrooms ............................................................. 4-6

Blower door test .................................................. 4-5

Building Energy Efficiency

ACM Reference Manual ............................. 1-4

Compliance Manual .................................... 1-4

Reference Appendices ............................... 1-4

Standards ................................................... 1-4

Buried ducts....................................................... 8-20

Cathedral ceiling .......................................... 6-3, 7-3

Cavity R-value ..................................................... 6-1

CBECC-Res .......................................................... 1-1 create a component .................................... 2-7 error message ............................................ 2-8 installing ...................................................... 2-1 menu bar .................................................... 2-1 project files ................................................. 2-8 right-click menu .......................................... 2-5 software updates ........................................ 1-2 status bar .................................................... 2-6 tool bar ........................................................ 2-3 tool tips ....................................................... 4-1 tutorial ......................................................... 3-1 i

CBECC User Manual

Ceiling

Below attic .................................................. 6-7

Interior ........................................................ 6-7

Ceiling below attic .............................................. 6-4

Ceiling height ...................................................... 5-6

CF1R

Generating draft ......................................... 2-3

Generating final.......................................... 1-3

Registering ................................................. 1-3

Watermark .......................................... 1-3, 2-3

CF1R registered ................................................... 4-3

CFM50 .................................................................. 4-5

Climate zone ................................................. 1-6, 4-2

Close cell spray foam insulation ....................... 6-2

Combined hydronic heating ........................... 8-11

Compliance manager ......................................... 1-5

Conditioned zone ............................................... 5-5

Controlled ventilation crawl space ................... 5-5

Cool roof .............................................................. 5-4

Cooling

Non-central systems ................................ 8-15

Cooling equipment types ................................ 8-13

Cooling ventilation ............................................. 4-9

CFI ........................................................... 8-23

COP to HSPF equation .............................. 8-6, 8-12

Crawl space ......................................................... 5-4

CVC ...................................................................... 5-5

Documentation author ....................................... 1-3

Domestic hot water system ............................... 5-7

Doors garage ........................................................ 7-7 opaque U-factor .......................................... 7-7 with glass .......................................... 7-6, 7-11

Duct Leakage

Target leakage .......................................... 8-17

Ducts ................................................................... 8-17 buried ........................................................ 8-19 bypass duct .............................................. 8-19

HERS verified conditions ......................... 8-19 type and location ...................................... 8-18

Dwelling unit....................................................... 4-7 multi-family ................................................. 4-7

EER

HERS verified EER ................................... 8-14

Electric radiant heat .......................................... 8-12

Electric resistance heat ..................................... 8-12

Emissivity see Emittance ............................................. 5-3

Emittance default ................................ 5-3, 6-12, 7-4

Error messages .................................................... 2-8

Evaporative cooling ................................... 8-1, 8-16

Fan efficacy ii

CBECC User Manual mandatory requirement ............................ 8-22

Federal appliance standard ............................... 4-3

Fenestration ......................................................... 7-8

Fins .......................................................... 7-10

Floor mandatory insulation .................................. 6-2 over exterior ............................................. 7-15 over garage .............................................. 6-18 raised ....................................................... 6-16

Floor area ............................................................. 5-6

Floor elevation .......................................... 7-15, 7-16

Floor furnace ..................................................... 8-12

Floor to floor ........................................................ 5-6

Frequently Asked Questions ............................. 2-3

Front orientation ................................................. 4-5

Garage .................................................................. 4-7 multi-family ................................................. 5-7 zone ........................................................... 5-7

Garage door ......................................................... 7-7

Geothermal heat pump .................................... 8-10

Ground source heat pump .............................. 8-10

Heat pump efficiency .................................................... 8-6

Heat Pump

Air to water source ............................ 8-8, 8-10

Ground source ............................ 8-1,

8-8, 8-10

Heat pump equipment types ............................ 8-8

Heated slab ........................................................ 7-17 heater .................................................................. 8-12

Heating equipment types .................................. 8-5

Heating system

AFUE standard for non-central ................. 8-12

Heating sytem

COP to HSPF equation .................... 8-6, 8-12

HERS Provider .................................................... 1-6

HERS registration

File for uploading .................................1-3, 4-3

High quality insulation ...................................... 4-5

HVAC different equipment types ........................... 5-1 multiple duct conditions .............................. 5-1 multiple systems ......................................... 8-4 supplemental heat ...................................... 8-4 zonal control ............................................... 5-1

HVAC System ..................................................... 5-7

Hydronic heating .............................................. 8-11

IAQ ventilation ................................................... 4-7 indoor air quality ventilation ............................ 4-8

Infiltration ............................................................ 4-5

Insulation quality ................................................ 4-5

Knee wall ............................................. 6-4, 6-15, 7-4

Low slope aggregate surface ............................. 5-4 iii

CBECC User Manual

Low slope roof .............................................. 5-4, 6-4 aged solar reflectance ............................... 6-4

Mandatory requirements ................................... 1-6

Mini-split .............................................................. 8-1

Multi-family building ......................................... 4-6 defining the building ................................... 4-6

Multiple conditioned zones ............................... 5-1

Multi-split ............................................................ 8-1

Natural gas availability ...................................... 4-6

No cooling .......................................................... 8-15 air leakage ................................................. 4-5

CFM/ton ................................................... 8-14

Watts/CFM ............................................... 8-22

Non-central heating minimum AFUE ........................................ 8-12

Number of stories ............................................... 5-6

Open cell spray foam insulation ....................... 6-2

Orientation building front .............................................. 4-5 walls ........................................................... 7-1

Package A ............................................................ 1-5

Project climate zone ............................................... 4-2 zip code ...................................................... 4-2

Proposed design .................................................. 1-5

PV System Credit ......................................... 4-3, 4-4 iv

QII ......................................................................... 4-5 spray foam insulation .................................. 6-2

Quick Start Guide ............................................... 2-3

Radiant barrier ............................................. 6-4, 6-6 in part of roof .............................................. 5-1

Rafter roof ............................................................ 6-3

Raised floor ............................................... 6-17, 7-13 crawl space zone ........................................ 5-4 over exterior .................................... 7-13, 7-16 over garage .............................................. 7-14

Registered CF1R .................................................. 1-3

Report manager................................................... 1-5

Return ducts ...................................................... 8-19

Roof ....................................................................... 6-4 above deck insulation ................................. 6-6 aged solar reflectance ............... 5-3, 6-12, 7-4 cathedral ceiling .......................................... 6-3 cool roof ...................................................... 5-4 emittance ................................... 5-3, 6-12, 7-4

Exceptions for emittance ............................ 5-3

Exceptions for solar reflectance ................. 5-3 insulation .................................................... 6-6 low slope ..................................................... 6-4 mandatory insulation .................................. 6-2 no attic ........................................................ 6-3 pitch .................................................. 6-11, 7-3 radiant barrier ............................................. 6-4

CBECC User Manual rafter roof ................................................... 6-3 raised heel truss......................................... 6-9 rise .................................................... 6-11, 7-3 solar reflectance................................ 6-12, 7-4 steep slope ................................................. 6-4

Roof construction ................................................ 5-3

Roof pitch ............................................................. 5-2

Roof rise ............................................................... 5-2

Room air ............................................................... 8-1

SEER

HERS verified high SEER ........................ 8-14

Single-family dwelling ....................................... 4-6

SIP Walls ............................................................ 6-15

Skylight .............................................................. 7-12

Slab...................................................................... 7-17 covered/exposed ..................................... 7-18 edge insulation ......................................... 7-18

Software updates ................................................ 1-2

Solar reflectance default ..................... 5-3, 6-12, 7-4

SPF closed cell .................................................. 6-2 default R-values ......................................... 6-3

Non-standard check box ............................ 6-2 open cell ..................................................... 6-2

Spray foam insulation verified insulation quality ............................ 6-2

Standard design .................................................. 1-5

Standards documents ......................................... 1-4

Standards version

Compliance 2014 ........................................ 4-3

Compliance 2015 ........................................ 4-3

Steep slope ........................................................... 5-4

Steep slope roof ................................................... 6-5 aged solar reflectance ................................ 6-5

Supply duct ....................................................... 8-18

Surface status ....................................................... 7-5

Thermal emittance default............................... 6-12

Ventilation cooling ............................................. 4-9 whole house fan ......................................... 4-9

Verified insulation quality ................................. 4-5

Wall

Advanced Wall Framing ............................. 6-3

Wall area .............................................................. 7-5

Wall furnace ...................................................... 8-12

Wall orientation .................................................. 7-6

Walls ................................................................... 6-12 between house and garage ...................... 6-15 demising ................................................... 6-15 garage exterior ......................................... 6-16 interior ....................................................... 6-15 knee walls .................................. 6-4, 6-15, 7-4

Mass ......................................................... 6-14 v

CBECC User Manual

Mass (ICF, brick, masonry, adobe) ......... 6-13

SIP .................................................. 6-13, 6-15

Steel ......................................................... 6-13

Strawbale ................................................. 6-13 uninsulated ............................................... 6-16

Water heater different types in same zone ...................... 5-1 distribution type ................................... 9-2, 9-4 heating element ......................................... 9-7 small or large ............................................. 9-1 solar fraction .............................................. 9-6 solar system ............................................... 9-5 standby loss ............................................... 9-8 tank type ............................................. 9-1, 9-7 type ............................................................ 9-1

Watts/CFM mandatory requirement ............................ 8-22 no cooling ................................................. 8-22

Whole house fan ................................................. 4-9

Window glass doors ............................................... 7-11 mandatory maximum U-factor .................... 7-7 multiplier ..................................................... 7-9 overall window area .................................... 7-8

SHGC ......................................................... 7-9 skylight ...................................................... 7-12

U-factor ....................................................... 7-9 window dimensions .................................... 7-8 window type ...................................... 6-19, 7-8

Window head height .......................................... 5-7

Window type .............................................. 6-19, 7-7

Wood heat .......................................................... 8-12

Zip code................................................................ 4-2

Zonal control ..................................4-6, 5-1, 5-6, 8-3 bypass duct .............................................. 8-18 multi-speed compressor ........................... 8-15

Zone type conditioned ................................................. 5-6 living or sleeping ......................................... 5-6 vi

CBECC-Res User Manual

Appendix A – Resolution approving CBECC-Res

A-1

Appendix A – Resolution approving CBECC-Res

CBECC-Res User Manual

Appendix B – CF1R

B-1

Appendix B – CF1R

CERTIFICATE OF COMPLIANCE - RESIDENTIAL PERFORMANCE COMPLIANCE METHOD

Project Name: 1 Story Example

Calculation Description: 1 Story Example Rev 12

Calculation Date/Time: 11:47, Wed, May 07,

2014

Input File Name: Exampl12.ribd

CF1R-PRF-01

Page 1 of 9

GENERAL INFORMATION

06

08

10

12

01

02

03

04

Project Name 1 Story Example

Calculation Description 2100 ft2 CEC Prototype with tile roof

Project Location 1516 Ninth St

A City Sacramento, CA

Zip code 95814

Climate Zone CZ12

Building Type Single Family

Project Scope Newly Constructed

14

16

Total Cond. Floor Area (FT

2

) 2100

Slab Area (FT

2

) 2100

Addition Cond. Floor Area NA 18

20

COMPLIANCE RESULTS

Addition Slab Area (FT

2

) NA

05

07

09

11

13

15

17

19

21

Standards Version Compliance 2015

Compliance Manager Version BEMCmpMgr 2013-2 (590)

Software Version CBECC-Res 2013-2 (592)

Front Orientation (deg/Cardinal) 90

Number of Dwelling Units 1

Number of Zones 1

Number of Stories 1

Natural Gas Available Yes

Glazing Percentage (%) 20.0%

01

02

03

Building Complies with Computer Performance

This building incorporates features that require field testing and/or verification by a certified HERS rater under the supervision of a CEC-approved HERS provider.

This building incorporates one or more Special Features shown below

04

Energy Use

(kTDV/ft)

Space Heating

Space Cooling

05

Standard

ENERGY USE SUMMARY

06

compliance

Compliance

Design

22.70

Proposed

Design for

11.78

Margin

-1.64

14.11

2.33

IAQ Ventilation

Water Heating

Photovoltaic Offset

1.13

13.86

----

TOTAL 51.80

useable

Not

Registration Number:

CA Building Energy Efficiency Standards - 2013 Residential Compliance

1.13

13.86

0.00

51.11

0.00

0.00

0.00

0.69

08

Percent

Improvement

-7.2%

16.5%

0.0%

0.0%

----

1.3%

Registration Date/Time:

Report Version - CF1R-04142014-574

Detailed help on using the CF-1R Certificate of

Compliance is available via the Internet by either scanning the QR code or browsing to http://www.title24energycode.org/t24help/cf1r.aspx

HERS Provider:

Report Generated at: 5/7/2014:11:49:18 AM

CERTIFICATE OF COMPLIANCE - RESIDENTIAL PERFORMANCE COMPLIANCE METHOD

Project Name: 1 Story Example

Calculation Description: 1 Story Example Rev 12

Calculation Date/Time: 11:47, Wed, May 07,

2014

Input File Name: Exampl12.ribd

REQUIRED SPECIAL FEATURES

The following are features that must be installed as condition for meeting the modeled energy performance for this computer analysis.

• Window overhangs and/or fins

HERS FEATURE SUMMARY

The following are features that must be installed as condition for meeting the modeled energy performance for this computer analysis.

• Window overhangs and/or fins

BUILDING - FEATURES INFORMATION

01

Project Name

1 Story Example

02

Conditioned Floor Area (sft)

2100

03

Number of Dwelling

Units

1

04

Number of Bedrooms

3

05

Number of Zones

1

ZONE INFORMATION

01 02 03 04 05

Zone Name

Conditioned

Zone Type

Conditioned

HVAC System Name

Zone Floor Area

(ft

2

)

HVAC System 1

compliance

2100

for

Avg. Ceiling

Height

9

06

Number of Ventilation

Cooling Systems

1

06

CF1R-PRF-01

Page 2 of 9

07

Number of Water

Heating Systems

1

07

Water Heating System 1 Water Heating System 2

Gas 60 EF

useable

Not

Registration Number:

CA Building Energy Efficiency Standards - 2013 Residential Compliance

Registration Date/Time:

Report Version - CF1R-04142014-574

HERS Provider:

Report Generated at: 5/7/2014:11:49:18 AM

CERTIFICATE OF COMPLIANCE - RESIDENTIAL PERFORMANCE COMPLIANCE METHOD

Project Name: 1 Story Example

Calculation Description: 1 Story Example Rev 12

Calculation Date/Time: 11:47, Wed, May 07,

2014

Input File Name: Exampl12.ribd

CF1R-PRF-01

Page 3 of 9

OPAQUE SURFACES

01 02

Zone

Conditioned

Conditioned

Conditioned

Conditioned

Conditioned

Conditioned>>Garage

Conditioned>>Garage

Garage

Garage

Garage

Garage

03

Construction

R15 R4 Stucco Wall

R15 R4 Stucco Wall

R15 R4 Stucco Wall

R15 R4 Stucco Wall

R38 Ceiling below attic

Gar House R15

Gar House R15

Garage Ext Wall

Garage Ext Wall

Garage Ext Wall

R0 ClgBlwAttic Cons

04

90

180

0

08

ATTIC

Name

Front

Left

Back

Right

Ceiling (below attic) 1

GarToHouse Front

GarToHouse Left

Gwall Front

Gwall Left

Gwall Right

Gceil

Azimuth

90

180

270

0

05 06 07

Orientation Gross Area (ft

2

) Window Area (ft

2

)

Front 270 100

Left

Back

Right

324

450

414

2100

56.04

207.32

56.04

Front

Left

Right

180

90

180

198

108

440

0

0

0

Tilt(deg)

90

90

90

90

90

90

90

WINDOWS

01

Name

F1

F2

01

Name

Attic

02

Type

Window

Window

02

Construction

Tile RB Roof

03 04

5

Roof Reflectance Roof Rise

compliance

0.2

for

03

Surface (Orientation-Azimuth)

Front (Front-90)

Front (Front-90)

04

Height

(ft)

5.0

5.0

L1

B1 SGD

Window

Window

Left (Left-180)

Back (Back-270)

4.7

7.7

B2

B3 SGD

R1

Window

Window

Window

useable Back (Back-270)

Back (Back-270)

Right (Right-0)

Not

Registration Number:

CA Building Energy Efficiency Standards - 2013 Residential Compliance

Registration Date/Time:

4.7

7.7

4.7

Report Version - CF1R-04142014-574

05

Roof Emittance

0.85

06

Radiant Barrier

Yes

05

Width(ft

)

06

Multiplie r

07

Area (ft

2

)

10.0

10.0

6.0

8.0

1

1

2

1

50.0

50.0

56.0

61.4

6.0

8.0

6.0

3

1

2

HERS Provider:

84.6

61.4

56.0

08

Ufactor

0.32

0.32

0.32

0.32

0.32

0.32

0.32

09

SHG

C

0.25

0.25

0.25

0.25

0.25

0.25

0.25

07

Cool Roof

No

10

Exterior Shading

Report Generated at: 5/7/2014:11:49:18 AM

CERTIFICATE OF COMPLIANCE - RESIDENTIAL PERFORMANCE COMPLIANCE METHOD

Project Name: 1 Story Example

Calculation Description: 1 Story Example Rev 12

Calculation Date/Time: 11:47, Wed, May 07,

2014

Input File Name: Exampl12.ribd

DOORS

01

Name

Front Dr

GarToHouse Dr

GDoor

OVERHANGS AND FINS

01 02

Overhang

Window

F1

F2

L1

B1 SGD

B2

B3 SGD

R1

6

6

6

1

Depth

1

1

1

03

Dist Up

1.33

1.33

1.33

1.33

1.33

1.33

1.33

04 05

Left

Extent

Left Fin

Right

Extent

3

28

6

4

23

28

3

8

40

23

02

Side of Building

Front

GarToHouse Front

Gwall Front

06

Flap Ht.

0.4

0.4

0.4

0.4

0.4

40 4 0.4

8

for

0.4

8

compliance

0

0

07

Depth

12

0

0

0

0

08

Right Fin

09

Top Up

1.33

0

0

0

0

0

0

0

0

0

0

DistL

1

0

0

10

Bot Up

0

0

0

0

0

0

0

03

Area (ft

2

)

20.0

20.0

108.0

11

0

0

0

0

Depth

0

0

0

CF1R-PRF-01

Page 4 of 9

04

U-factor

0.50

0.50

1.00

12 13 14

Top Up

0

0

0

0

0

0

0

0

0

0

0

Dist R Bot Up

0 0

0

0

0

0

0

0

0

0

useable

Not

Registration Number:

CA Building Energy Efficiency Standards - 2013 Residential Compliance

Registration Date/Time:

Report Version - CF1R-04142014-574

HERS Provider:

Report Generated at: 5/7/2014:11:49:18 AM

CERTIFICATE OF COMPLIANCE - RESIDENTIAL PERFORMANCE COMPLIANCE METHOD

Project Name: 1 Story Example

Calculation Description: 1 Story Example Rev 12

Calculation Date/Time: 11:47, Wed, May 07,

2014

Input File Name: Exampl12.ribd

OPAQUE SURFACE CONSTRUCTIONS

01

Construction Name

02

Surface Type

R0 ClgBlwAttic Cons

Gar House R15

Tile RB Roof

R38 Ceiling below attic

R15 R4 Stucco Wall

Ceilings (below attic)

Interior Walls

Attic Roofs

Ceilings (below attic)

Exterior Walls

Garage Ext Wall Exterior Walls

OPAQUE SURFACES – Cathedral Ceilings

01 02

03

Construction Type

Wood Framed Ceiling

Wood Framed Wall

Wood Framed Ceiling

Wood Framed Ceiling

04

Framing

2x4 Bottom Chord of

Truss @ 24 in. O.C.

2x4 @ 16 in. O.C.

2x4 @ 24 in. O.C.

2x4 Bottom Chord of

Truss @ 24 in. O.C.

2x4 @ 16 in. O.C.

Wood Framed Wall compliance

03

Name Zone

useable

Not

Registration Number:

CA Building Energy Efficiency Standards - 2013 Residential Compliance

Type

2x4 @ 16 in. O.C.

05

Total Cavity R-value

R 15

R 38

R 15

- no insulation

(vertical) -

04 05 06 07 08

Orientation Area (ft

2

)

Roof Risee (x in

12) Roof Pitch

Roof

Tilt(deg)

09

Roof

Reflectanc e

10

Roof

Emmitta nce

11

Framing

Factor

Registration Date/Time:

Report Version - CF1R-04142014-574

06

Assembly Layers

Attic Floor: - no attic floor -

Cavity: - no insulation -

SheathingInsulation - no sheathing/insul. -

Inside Finish: Gypsum Board

Inside Finish: Gypsum Board

Sheathing/Insulation: - no sheathing/insul. -

Cavity: R 15

Sheathing/Insulation: - no sheathing/insul. -

Other Side FInish: Gypsum Board

Roofing: 10 PSF (RoofTile)

Above Deck Insulation - no insulation -

Roof Deck: Wood Siding/sheathing/decking

Cavity: - no insulation -

Inside Finish: - select inside finish -

Attic Floor: - no attic floor -

Cavity: R 38

SheathingInsulation - no sheathing/insul. -

Inside Finish: Gypsum Board

Inside Finish: Gypsum Board

Sheathing/Insulation: - no sheathing/insul. -

Cavity: R 15

Sheathing/Insulation: - no sheathing/insul. -

Exterior Finish: R4 Synthetic Stucco

Inside Finish: Gypsum Board

Sheathing/Insulation: - no sheathing/insul. -

Cavity: - no insulation (vertical) -

Sheathing/Insulation: - no sheathing/insul. -

Exterior Finish: 3 Coat Stucco

HERS Provider:

CF1R-PRF-01

Page 5 of 9

Report Generated at: 5/7/2014:11:49:18 AM

CERTIFICATE OF COMPLIANCE - RESIDENTIAL PERFORMANCE COMPLIANCE METHOD

Project Name: 1 Story Example

Calculation Description: 1 Story Example Rev 12

Calculation Date/Time: 11:47, Wed, May 07,

2014

Input File Name: Exampl12.ribd

CF1R-PRF-01

Page 6 of 9

SLAB FLOORS

01

Name

Slab On Grade 2

Gslab

BUILDING ENVELOPE - HERS VERIFICATION

01

Quality Insulation Installation(QII)

NOT REQUIRED

WATER HEATING SYSTEMS

01

Name

Gas 60 EF

WATER HEATERS

01 02

02

Zone

Conditioned

Garage

02

03

Area (ft

2

2100

440

)

Quality Installation of Spray Foam Insulation

NOT REQUIRED

02

Distribution Type

Standard

Name Heater Element Type

50 Gal Gas

WATER HEATING - HERS VERIFICATION

Natural Gas

01 02

Name

Gas 60 EF-hers-dhw

HVAC SYSTEMS

Pipe Insulation n/a

04

Perimeter (ft)

162

44

03 04 05

Tank Volume

Tank Type

Small Storage

(gal)

compliance

for

03

Parallel Piping

Energy Factor or

Efficiency

04

0.6

Compact Distribution n/a n/a

05

05 06

Edge Insul. R-value& Depth Carpeted Fraction

None 0.8

None 0

03

Building Envelope Air Leakage

NOT REQUIRED

03

Number of Heaters

1

06

Input Rating

40000-Btu/hr

Point-of Use n/a

04

ACH @ 50 Pa

---

04

Solar Fraction (%)

NaN

07

Tank Exterior

Insulation R-value

0

06

Recirculation with

Manual Control

07

Heated

No

No

08

Standby Loss

(Fraction)

0

07

Recirculation with

Sensor Control n/a

01 02

Name

HVAC System 1

useable

Other Heating and Cooling System

Not

Registration Number:

CA Building Energy Efficiency Standards - 2013 Residential Compliance

03

Heating System

Name

Min Furn 78

Ducted

Yes

04

Cooling System

Name

Cooling Min

Registration Date/Time:

Report Version - CF1R-04142014-574

Ducted

Yes

HERS Provider:

05

Distribution

System

Attic Default

06

Fan System

HVAC Fan 1

07

Floor Area

Served

2100

Report Generated at: 5/7/2014:11:49:18 AM

CERTIFICATE OF COMPLIANCE - RESIDENTIAL PERFORMANCE COMPLIANCE METHOD

Project Name: 1 Story Example

Calculation Description: 1 Story Example Rev 12

Calculation Date/Time: 11:47, Wed, May 07,

2014

Input File Name: Exampl12.ribd

CF1R-PRF-01

Page 7 of 9

HVAC - HEATING SYSTEMS

01

Name

Min Furn 78

HVAC - COOLING SYSTEMS

01

Name

Cooling Min

HVAC COOLING - HERS VERIFICATION

01 02

02

Type

CntrlFurnace - Fuel-fired central furnace

02

System Type

SplitAirCond - Split air conditioning system

03

03

EER

11.3

Efficiency

04

04

SEER

13

05

03

Efficiency

78 AFUE

05

HERS Verification

Cooling Min-hers-cool

Name

Cooling Min-hers-cool

HVAC - DISTRIBUTION SYSTEMS

Verified Airflow

Required

Airflow Target

350

Verified EER

Not Required

Verified SEER

Not Required

06

Verified Refrigerant

Charge

Required

01 02 03 04 05

Name

Attic Default

01

Name

Type

Ducts located in unconditioned attic

HVAC DISTRIBUTION - HERS VERIFICATION

02

Duct Leakage Verification

Duct Leakage

Sealed and tested

Insulation R-value compliance

for

03

Supply Duct

Location

Attic

Duct Leakage Target (%)

06

Return Duct

Attic

04

Verified Duct Location

Attic Default-hers-dist Required 6.0

Not Required

HVAC - FAN SYSTEMS

01

Name

HVAC Fan 1

useable 02

Type

Single Speed PSC Furnace Fan

Not

Registration Number:

CA Building Energy Efficiency Standards - 2013 Residential Compliance

Registration Date/Time:

Report Version - CF1R-04142014-574

03

Fan Power (Watts/CFM)

0.58

HERS Provider:

07

Bypass Duct

None

04

HERS Verification

Required

08

HERS Verification

Attic Default-hers-dist

05 06

Verified Duct Design

Return Supply

Not Required Not Required

Report Generated at: 5/7/2014:11:49:18 AM

CERTIFICATE OF COMPLIANCE - RESIDENTIAL PERFORMANCE COMPLIANCE METHOD

Project Name: 1 Story Example

Calculation Description: 1 Story Example Rev 12

Calculation Date/Time: 11:47, Wed, May 07,

2014

Input File Name: Exampl12.ribd

HVAC FAN SYSTEMS - HERS VERIFICATION

01

Name

HVAC Fan 1-hers-fan

IAQ (Indoor Air Quality) FANS

01

Name

IAQ Fan

COOLING VENTILATION

01

Name

Whole House Fan

02

IAQ CFM

51

02

Cooling Vent CFM

4200

02

VerifiedFanWatt Draw

Required

03

IAQ Fan Type

Exhaust

03

Cooling Vent Watts/CFM

0.1

04

IAQ Recovery Effectiveness(%)

0

04

Number of Fans

1

CF1R-PRF-01

Page 8 of 9

03

Required Fan Efficiency (Watts/CFM)

0.58

05

HERS Verification

Required

05

HERS Verification

for

compliance

useable

Not

Registration Number:

CA Building Energy Efficiency Standards - 2013 Residential Compliance

Registration Date/Time:

Report Version - CF1R-04142014-574

HERS Provider:

Report Generated at: 5/7/2014:11:49:18 AM

CERTIFICATE OF COMPLIANCE - RESIDENTIAL PERFORMANCE COMPLIANCE METHOD

Project Name: 1 Story Example

Calculation Description: 1 Story Example Rev 12

Calculation Date/Time: 11:47, Wed, May 07,

2014

Input File Name: Exampl12.ribd

DOCUMENTATION AUTHOR'S DECLARATION STATEMENT

1. I certify that this Certificate of Compliance documentation is accurate and complete.

Documentation Author Name: Documentation Author Signature:

Company:

Address:

Signature Date:

CEA/HERS Certification Identification (If applicable):

CF1R-PRF-01

Page 9 of 9

City/State/Zip:

RESPONSIBLE PERSON'S DECLARATION STATEMENT

Phone:

I certify the following under penalty of perjury, under the laws of the State of California:

1.

I am eligible under Division 3 of the Business and Professions Code to accept responsibility for the building design identified on this Certificate of Compliance.

2.

I certify that the energy features and performance specifications identified on this Certificate of Compliance conform to the requirements of Title 24, Part 1 and Part 6 of the California Code of

3.

Regulations.

The building design features or system design features identified on this Certificate of Compliance are consistent with the information provided on other applicable compliance documents, worksheets, calculations, plans and specifications submitted to the enforcement agency for approval with this building permit application.

Responsible Designer Name: ResponsibleDesigner Signature:

Date Signed: Company:

Address:

City/State/Zip:

for

Phone:

useable

Not

Registration Number:

CA Building Energy Efficiency Standards - 2013 Residential Compliance

Registration Date/Time:

Report Version - CF1R-04142014-574

HERS Provider:

Report Generated at: 5/7/2014:11:49:18 AM

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