Slab Insulation

Slab Insulation
Technology
SLAB INSULATION
For more information, contact:
Energy Efficiency and
Renewable Energy
Clearinghouse (EREC)
1-800-DOE-3732
www.eren.doe.gov
Or visit the BTS Web site at
www.eren.doe.gov/buildings
Or refer to the Builder’s Guide
Energy Efficient Building
Association, Inc.
651-268-7585
www.eeba.org
Written and prepared for
the U.S. Department of
Energy by:
Southface Energy Institute
404-872-3549
www.southface.org
U.S. Department of
Energy’s Oak Ridge
National Laboratory
Buildings Technology Center
423-574-5178
www.ornl.gov/ORNL/BTC
The International Energy
Conservation Code
can be obtained from the
International Code Council by
calling 703-931-4533
www.intlcode.org
MECcheck, a companion
compliance software
package, can be ordered from
DOE by calling
1-800-270-CODE
or from the Web at
www.energycodes.org/
resid/resid.htm.
NOTICE: Neither the United
States government nor any
agency thereof, nor any of their
employees, makes any warranty,
express or implied, or assumes
any legal liability or responsibility
for the accuracy, completeness,
or usefulness of any information,
apparatus, product, or process
disclosed. The views and opinions of authors expressed herein
do not necessarily state or reflect
those of the United States government or any agency thereof.
SPECIAL REQUIREMENTS OF SLAB
INSULATION FOR TERMITE CONTROL
Over the past decade, reports of termite
infestations in homes with exterior slab
insulation have become more frequent. These
pests tunnel undetected through the insulation
to gain access to the wood framing in the
walls. Some insurance companies no longer
guarantee homes with slab insulation against
termite damage. Recent rulings by national
code organizations, such as the International
Code Council, prohibit installing foam
FOLLOW
Provide effective moisture control systems.
•
Remove all wood from around the
foundation before backfilling.
•
Install termite shields continuously under the
sill plate of the building. While not 100
percent effective, the termite shield may deter
or delay widespread infestation and may also
force termites into an exposed area where they
can be detected. It should project beyond the
sill plate and all other portions of the exterior
wall. A continuous layer of a membrane such
as rubberized roofing material used in
insulation in contact with the ground in several
southern states (South Carolina, Florida,
Georgia, Alabama, Mississippi, Louisiana,
Arkansas, and Texas).
An alternative to slab edge insulation is to
create a contained or floating slab with interior
foam insulation. This non-monolithic approach
provides termite resistance because the
insulation is sealed within the slab. However,
builders in the Southeast United States recently
reported termite infestations through foam
insulation on contained slabs.
Termite prevention is a key goal when installing
slab insulation, especially where a visual
inspection of the foundation is not possible.
The key to controlling termites is proper
treatment, a regular inspection policy, and a
strong warranty from a termite company.
Before construction, confer with a pest control
company to ensure a favorable termite
contract.
commercial buildings may be used as an
alternative to the termite shield.
•
Use a foam insulation with a termiticide.
Usually a derivative of boric acid, the
termiticide should pose no more threat to
home owners than traditional termite
treatments. One of the nation’s leading foam
insulation manufacturers is planning to offer
a termite-treated insulation board on the
market in the year 2000 or 2001.
Improve comfort and save energy
in homes with slab-on-grade floors
Buildings for
the 21st Century
Buildings that are more
energy efficient, comfortable,
and affordable…that’s the
goal of DOE’s Office of Building
Technology, State and
Community Programs (BTS).
To accelerate the development
and wide application of energy
efficiency measures, BTS:
• Conducts R&D on technologies
and concepts for energy efficiency, working closely with
the building industry and with
manufacturers of materials,
equipment, and appliances
• Promotes energy/money
saving opportunities to both
builders and buyers of homes
and commercial buildings
• Works with state and local
regulatory groups to improve
building codes, appliance standards, and guidelines for efficient energy use
• Provides support and grants
to states and communities
for deployment of energyefficient technologies and
practices
SLAB-ON-GRADE FLOORS PROVIDE AN
INEXPENSIVE AND VERSATILE FOUNDATION
Slab-on-grade floors are often the least expensive foundation system and can expedite the
construction process. The foundation consists
of a concrete slab poured over at least 4 inches
of gravel and a layer of 10-mil polyethylene.
SLAB INSULATION
Provides a thermal break to the perimeter
of slab-on-grade foundations.
Virtually any floor covering works well with a
slab, although wood flooring systems may
require installation of wooden furring strips
prior to attaching the wood flooring material.
Homes use slab-on-grade floors in two ways:
either as the bottom floor of a home or as the
floor in a daylight basement—where the floor
level is about even with outside earth. Areas
with mild winters do not require a deep foundation.
In these regions, slab-on-grade foundations may
prove an ideal choice for flat lots.
Care must be taken in designing a home with a
slab foundation to avoid a “squat” appearance.
For example, porches are at grade level in
houses with a slab foundation, rather than
being elevated above the yard. The hard
surface of the slab foundation may cause
injuries, more frequent breakage of dropped
objects, and tired feet unless it is covered with
carpeting or other softer floor finishes. Use of
slab foundations can also make it more difficult
to install wiring, plumbing, and ductwork, so
the design of these systems into the
construction plans and process is essential.
BENEFITS OF INSULATING
SLAB-ON-GRADE FLOORS
Slabs lose energy primarily as a result of heat
conducted outward and through the perimeter
of the slab. In most sections of the country,
insulating the exterior edge of the slab can
reduce winter heating bills by 10 to 20 percent.
In climates with mild winters, slab insulation in
a typical 1,800 square-foot home would save
$50 to $60 annually. R-10 slab insulation for
an 1,800 square-foot home would typically
cost $300 to $600 to install. Thus, the insulation would pay for itself in 5 to 10 years.
The investment in slab insulation is also
economical when it is part of the mortgage. An
insulation cost of $450 would add about $38
to the annual mortgage. Since the insulation
saves over $50 per year on energy bills,
savings exceed the extra mortgage costs and
the investment in slab insulation pays off from
the beginning.
Slab insulation is important not only to save on
energy bills, but also to improve comfort. Cold
concrete slabs are one of the most notorious
sources of discomfort in a home. Installing
slab insulation around the perimeter of the slab
will reduce heat loss and make the slab easier
to heat. An insulated slab also provides
thermal mass to store heat and moderates
indoor temperatures.
Printed with a renewable-source ink on paper containing at
least 50% wastepaper, including 20% postconsumer waste.
December 2000
DOE/GO102000-0775
Sheet
SLAB INSULATION
THESE GUIDELINES TO OFFSET
TERMITE PROBLEMS:
•
Fact
OFFICE OF BUILDING TECHNOLOGY, STATE AND COMMUNITY PROGRAMS
ENERGY EFFICIENCY AND RENEWABLE ENERGY • U.S. DEPARTMENT OF ENERGY
SLAB INSULATION
SLAB INSULATION TECHNIQUES
Slab insulation can be installed following one of two basic
techniques: installing rigid insulation directly against the
exterior of the slab and footing or building a “contained” or
“floating” slab with interior insulation. Whichever design is
followed, the keys to an effective slab foundation are:
MOISTURE AND AIR LEAKAGE CONTROL
1. Keep all untreated wood materials away from the earth.
Moisture control—using a water-managed foundation system
to drain rainwater and groundwater away from the foundation.
3. Slope the earth away from the house for at least 5 feet at a
minimum 5% grade (3 inches in 5 feet). Establish drainage
swales as needed to direct rainwater around the house.
Airtight construction—sealing interfaces between the slab
foundation and the exterior wall to reduce infiltration into
the house.
4. Add a sill gasket membrane between the slab and bottom plate
to provide air sealing.
Complete insulation coverage—properly installing the correct
insulation levels and making sure the insulation coverage is
continuous and complete.
PERIMETER INSULATION—
SLAB-ON-GRADE CONSTRUCTION
Provide good drainage away from the foundation and
capillary breaks for a durable foundation. Perimeter
insulation increases comfort in the living space.
Metal termite
flashing
Sill gasket
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Rigid insulation
encapsulated or
covered with
membrane to
protect from
termites and
exterior
damage.
Gravel
base
Perforated drainage pipe is embedded in gravel,
covered with filter fabric, and located at lower
perimeter of foundation footing to provide drainage.
10-mil poly vapor
diffusion retarder is
extented under
footing.
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FLOATING SLAB-ON-GRADE CONSTRUCTION
Sill gasket
R-VALUES AND RECOMMENDED DEPTH FOR
SLAB INSULATION
The IECC specifies both the R-value of the slab insulation and the minimum distance for the insulation from
the top of the slab downward based on a locality’s
Heating Degree Days (HDDs):
2. Install well-designed guttering and downspouts that are
connected to a drainage system diverting rainwater completely
away from the house.
Heating
Degree Days
0 to 2,499
2,499 to 4,500
4,500 to 6,000
6,000 to 7,200
7,200 to 8,700
8,700 to 10,000
10,000 to 12,400
12,400 to 14,000
5. Install a protective membrane (such as rubberized roofing
material or ice-dam protection membranes) to serve as a
capillary break that reduces wicking of water up from the
foundation. This membrane can also serve as a termite shield.
6. Install a foundation drain directly beside the bottom of the
footing. The foundation drain assembly includes a filter
fabric, gravel, and a perforated plastic drain pipe typically
4 inches in diameter. Locate the drain beside the footing, not
on top, to avoid water flowing against the seam between the
footing and the foundation wall and prevent wicking from a
web footing through the stem wall.
HDD=HEATING DEGREE DAYS
(Consult your local weather bureau for your city’s actual
annual Heating Degree Days.) Heating Degree Days is a
term used to help indicate the heating needed for any
certain day. This method is commonly used to determine
fuel consumption and/or the cost of heating during a
season by using historical weather trends to calculate
average seasonal temperatures.
7. Install a capillary break and moisture barrier under the slab
floor, consisting of a layer of 10-mil polyethylene placed over
at least 4 inches of gravel.
INSULATION
1. Review the plan for slab insulation with pest control and local
building officials to ensure code compliance.
2. Select insulation levels in accordance with the International
Energy Conservation Code (IECC) or DOE Insulation Fact
Sheet. The Insulation Fact Sheet (DOE/CE-0180) can be
ordered from the Energy Efficiency and Renewable Energy
Clearinghouse or accessed from the Internet at
4. If insulation is installed on the exterior of the slab:
•
•
www.ornl.gov/roofs+walls.
Rigid insulation
Metal termite
flashing
Gravel
base
Perforated drainage pipe is embedded in gravel,
covered with filter fabric, and located at lower perimeter
of foundation footing to provide drainage.
10-mil poly
vapor diffusion
retarder
3. Install rigid insulation using one of the two general designs
shown to achieve complete insulation coverage of the slab
perimeter. Use only insulation approved for below-grade use.
Feet Installed
R-value of
Vertically
Slab Insulation
none required
2 feet
R-4
2 feet
R-5
4 feet
R-6
4 feet
R-7
4 feet
R-8
4 feet
R-9
4 feet
R-10
•
The insulation should be installed from the top of the slab
to the bottom of the frost line unless a termite inspection
gap is required.
Encapsulate or cover the exterior face of the insulation
with a protective membrane to serve as a capillary break
and to protect the insulation from termites.
Cover the above-grade portion of the insulation exposed
to outside air using a stucco coating, pressure-treated
wood, brick, or aluminum flashing. When covering
insulation, be conscious of how to detect termites in areas
prone to termite infestation. Some states in termite-prone
areas have addressed this issue by requiring a termite
inspection gap near the top of the slab insulation.
BUILD IN RADON RESISTANCE WHEN INSTALLING
SLAB-ON-GRADE FOUNDATIONS
Radon is a radioactive gas that occurs in some soils. It can
enter a home through the foundation and floor system. If it
occurs in significant concentrations (greater than 4 pico-curies
per liter), it may pose a severe health risk to the home
occupants. To guard against radon problems in concrete slabs:
•
Use a 4- to 6-inch gravel base and a continuous layer of 10-mil
polyethylene on top of the gravel.
•
Install a tee below the polyethylene that protrudes through the
polyethylene and extends above the poured floor height.
•
Connect the tee to a 3-inch vertical plastic pipe that extends to
the roof through an interior wall.
•
Pour the slab and seal all slab joints with caulk.
•
Have an electrician stub-in a junction box in the attic.
•
Test the bottom-most conditioned room for radon with an
EPA-listed radon test kit, or hire a qualified technician. If the
house has a high radon concentration, install an active radon
mitigation system by attaching a small blower to the plastic
pipe in the attic to expel the gasses to the outside.
•
If radon levels are especially high (over 25 pico-curies per
liter), consult with local radon experts.
RADON-RESISTANT
CONSTRUCTION
Passive
radon-resistant
construction is an
inexpensive first
cost. It can easily be
upgraded if active
mitigation is later
required to cure a
radon problem.
Optional blower
(if required)
Electrical
junction box
Plastic
vent stack
Sealed
polyethylene
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SLAB INSULATION
SLAB INSULATION TECHNIQUES
Slab insulation can be installed following one of two basic
techniques: installing rigid insulation directly against the
exterior of the slab and footing or building a “contained” or
“floating” slab with interior insulation. Whichever design is
followed, the keys to an effective slab foundation are:
MOISTURE AND AIR LEAKAGE CONTROL
1. Keep all untreated wood materials away from the earth.
Moisture control—using a water-managed foundation system
to drain rainwater and groundwater away from the foundation.
3. Slope the earth away from the house for at least 5 feet at a
minimum 5% grade (3 inches in 5 feet). Establish drainage
swales as needed to direct rainwater around the house.
Airtight construction—sealing interfaces between the slab
foundation and the exterior wall to reduce infiltration into
the house.
4. Add a sill gasket membrane between the slab and bottom plate
to provide air sealing.
Complete insulation coverage—properly installing the correct
insulation levels and making sure the insulation coverage is
continuous and complete.
PERIMETER INSULATION—
SLAB-ON-GRADE CONSTRUCTION
Provide good drainage away from the foundation and
capillary breaks for a durable foundation. Perimeter
insulation increases comfort in the living space.
Metal termite
flashing
Sill gasket
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Rigid insulation
encapsulated or
covered with
membrane to
protect from
termites and
exterior
damage.
Gravel
base
Perforated drainage pipe is embedded in gravel,
covered with filter fabric, and located at lower
perimeter of foundation footing to provide drainage.
10-mil poly vapor
diffusion retarder is
extented under
footing.
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FLOATING SLAB-ON-GRADE CONSTRUCTION
Sill gasket
R-VALUES AND RECOMMENDED DEPTH FOR
SLAB INSULATION
The IECC specifies both the R-value of the slab insulation and the minimum distance for the insulation from
the top of the slab downward based on a locality’s
Heating Degree Days (HDDs):
2. Install well-designed guttering and downspouts that are
connected to a drainage system diverting rainwater completely
away from the house.
Heating
Degree Days
0 to 2,499
2,499 to 4,500
4,500 to 6,000
6,000 to 7,200
7,200 to 8,700
8,700 to 10,000
10,000 to 12,400
12,400 to 14,000
5. Install a protective membrane (such as rubberized roofing
material or ice-dam protection membranes) to serve as a
capillary break that reduces wicking of water up from the
foundation. This membrane can also serve as a termite shield.
6. Install a foundation drain directly beside the bottom of the
footing. The foundation drain assembly includes a filter
fabric, gravel, and a perforated plastic drain pipe typically
4 inches in diameter. Locate the drain beside the footing, not
on top, to avoid water flowing against the seam between the
footing and the foundation wall and prevent wicking from a
web footing through the stem wall.
HDD=HEATING DEGREE DAYS
(Consult your local weather bureau for your city’s actual
annual Heating Degree Days.) Heating Degree Days is a
term used to help indicate the heating needed for any
certain day. This method is commonly used to determine
fuel consumption and/or the cost of heating during a
season by using historical weather trends to calculate
average seasonal temperatures.
7. Install a capillary break and moisture barrier under the slab
floor, consisting of a layer of 10-mil polyethylene placed over
at least 4 inches of gravel.
INSULATION
1. Review the plan for slab insulation with pest control and local
building officials to ensure code compliance.
2. Select insulation levels in accordance with the International
Energy Conservation Code (IECC) or DOE Insulation Fact
Sheet. The Insulation Fact Sheet (DOE/CE-0180) can be
ordered from the Energy Efficiency and Renewable Energy
Clearinghouse or accessed from the Internet at
4. If insulation is installed on the exterior of the slab:
•
•
www.ornl.gov/roofs+walls.
Rigid insulation
Metal termite
flashing
Gravel
base
Perforated drainage pipe is embedded in gravel,
covered with filter fabric, and located at lower perimeter
of foundation footing to provide drainage.
10-mil poly
vapor diffusion
retarder
3. Install rigid insulation using one of the two general designs
shown to achieve complete insulation coverage of the slab
perimeter. Use only insulation approved for below-grade use.
Feet Installed
R-value of
Vertically
Slab Insulation
none required
2 feet
R-4
2 feet
R-5
4 feet
R-6
4 feet
R-7
4 feet
R-8
4 feet
R-9
4 feet
R-10
•
The insulation should be installed from the top of the slab
to the bottom of the frost line unless a termite inspection
gap is required.
Encapsulate or cover the exterior face of the insulation
with a protective membrane to serve as a capillary break
and to protect the insulation from termites.
Cover the above-grade portion of the insulation exposed
to outside air using a stucco coating, pressure-treated
wood, brick, or aluminum flashing. When covering
insulation, be conscious of how to detect termites in areas
prone to termite infestation. Some states in termite-prone
areas have addressed this issue by requiring a termite
inspection gap near the top of the slab insulation.
BUILD IN RADON RESISTANCE WHEN INSTALLING
SLAB-ON-GRADE FOUNDATIONS
Radon is a radioactive gas that occurs in some soils. It can
enter a home through the foundation and floor system. If it
occurs in significant concentrations (greater than 4 pico-curies
per liter), it may pose a severe health risk to the home
occupants. To guard against radon problems in concrete slabs:
•
Use a 4- to 6-inch gravel base and a continuous layer of 10-mil
polyethylene on top of the gravel.
•
Install a tee below the polyethylene that protrudes through the
polyethylene and extends above the poured floor height.
•
Connect the tee to a 3-inch vertical plastic pipe that extends to
the roof through an interior wall.
•
Pour the slab and seal all slab joints with caulk.
•
Have an electrician stub-in a junction box in the attic.
•
Test the bottom-most conditioned room for radon with an
EPA-listed radon test kit, or hire a qualified technician. If the
house has a high radon concentration, install an active radon
mitigation system by attaching a small blower to the plastic
pipe in the attic to expel the gasses to the outside.
•
If radon levels are especially high (over 25 pico-curies per
liter), consult with local radon experts.
RADON-RESISTANT
CONSTRUCTION
Passive
radon-resistant
construction is an
inexpensive first
cost. It can easily be
upgraded if active
mitigation is later
required to cure a
radon problem.
Optional blower
(if required)
Electrical
junction box
Plastic
vent stack
Sealed
polyethylene
;;;;;;;;;;;;;
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€€€€€€€€€€€€€
ÀÀÀÀÀÀÀÀÀÀÀÀÀ
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Perforated "T" fitting
Technology
SLAB INSULATION
For more information, contact:
Energy Efficiency and
Renewable Energy
Clearinghouse (EREC)
1-800-DOE-3732
www.eren.doe.gov
Or visit the BTS Web site at
www.eren.doe.gov/buildings
Or refer to the Builder’s Guide
Energy Efficient Building
Association, Inc.
651-268-7585
www.eeba.org
Written and prepared for
the U.S. Department of
Energy by:
Southface Energy Institute
404-872-3549
www.southface.org
U.S. Department of
Energy’s Oak Ridge
National Laboratory
Buildings Technology Center
423-574-5178
www.ornl.gov/ORNL/BTC
The International Energy
Conservation Code
can be obtained from the
International Code Council by
calling 703-931-4533
www.intlcode.org
MECcheck, a companion
compliance software
package, can be ordered from
DOE by calling
1-800-270-CODE
or from the Web at
www.energycodes.org/
resid/resid.htm.
NOTICE: Neither the United
States government nor any
agency thereof, nor any of their
employees, makes any warranty,
express or implied, or assumes
any legal liability or responsibility
for the accuracy, completeness,
or usefulness of any information,
apparatus, product, or process
disclosed. The views and opinions of authors expressed herein
do not necessarily state or reflect
those of the United States government or any agency thereof.
SPECIAL REQUIREMENTS OF SLAB
INSULATION FOR TERMITE CONTROL
Over the past decade, reports of termite
infestations in homes with exterior slab
insulation have become more frequent. These
pests tunnel undetected through the insulation
to gain access to the wood framing in the
walls. Some insurance companies no longer
guarantee homes with slab insulation against
termite damage. Recent rulings by national
code organizations, such as the International
Code Council, prohibit installing foam
FOLLOW
Provide effective moisture control systems.
•
Remove all wood from around the
foundation before backfilling.
•
Install termite shields continuously under the
sill plate of the building. While not 100
percent effective, the termite shield may deter
or delay widespread infestation and may also
force termites into an exposed area where they
can be detected. It should project beyond the
sill plate and all other portions of the exterior
wall. A continuous layer of a membrane such
as rubberized roofing material used in
insulation in contact with the ground in several
southern states (South Carolina, Florida,
Georgia, Alabama, Mississippi, Louisiana,
Arkansas, and Texas).
An alternative to slab edge insulation is to
create a contained or floating slab with interior
foam insulation. This non-monolithic approach
provides termite resistance because the
insulation is sealed within the slab. However,
builders in the Southeast United States recently
reported termite infestations through foam
insulation on contained slabs.
Termite prevention is a key goal when installing
slab insulation, especially where a visual
inspection of the foundation is not possible.
The key to controlling termites is proper
treatment, a regular inspection policy, and a
strong warranty from a termite company.
Before construction, confer with a pest control
company to ensure a favorable termite
contract.
commercial buildings may be used as an
alternative to the termite shield.
•
Use a foam insulation with a termiticide.
Usually a derivative of boric acid, the
termiticide should pose no more threat to
home owners than traditional termite
treatments. One of the nation’s leading foam
insulation manufacturers is planning to offer
a termite-treated insulation board on the
market in the year 2000 or 2001.
Improve comfort and save energy
in homes with slab-on-grade floors
Buildings for
the 21st Century
Buildings that are more
energy efficient, comfortable,
and affordable…that’s the
goal of DOE’s Office of Building
Technology, State and
Community Programs (BTS).
To accelerate the development
and wide application of energy
efficiency measures, BTS:
• Conducts R&D on technologies
and concepts for energy efficiency, working closely with
the building industry and with
manufacturers of materials,
equipment, and appliances
• Promotes energy/money
saving opportunities to both
builders and buyers of homes
and commercial buildings
• Works with state and local
regulatory groups to improve
building codes, appliance standards, and guidelines for efficient energy use
• Provides support and grants
to states and communities
for deployment of energyefficient technologies and
practices
SLAB-ON-GRADE FLOORS PROVIDE AN
INEXPENSIVE AND VERSATILE FOUNDATION
Slab-on-grade floors are often the least expensive foundation system and can expedite the
construction process. The foundation consists
of a concrete slab poured over at least 4 inches
of gravel and a layer of 10-mil polyethylene.
SLAB INSULATION
Provides a thermal break to the perimeter
of slab-on-grade foundations.
Virtually any floor covering works well with a
slab, although wood flooring systems may
require installation of wooden furring strips
prior to attaching the wood flooring material.
Homes use slab-on-grade floors in two ways:
either as the bottom floor of a home or as the
floor in a daylight basement—where the floor
level is about even with outside earth. Areas
with mild winters do not require a deep foundation.
In these regions, slab-on-grade foundations may
prove an ideal choice for flat lots.
Care must be taken in designing a home with a
slab foundation to avoid a “squat” appearance.
For example, porches are at grade level in
houses with a slab foundation, rather than
being elevated above the yard. The hard
surface of the slab foundation may cause
injuries, more frequent breakage of dropped
objects, and tired feet unless it is covered with
carpeting or other softer floor finishes. Use of
slab foundations can also make it more difficult
to install wiring, plumbing, and ductwork, so
the design of these systems into the
construction plans and process is essential.
BENEFITS OF INSULATING
SLAB-ON-GRADE FLOORS
Slabs lose energy primarily as a result of heat
conducted outward and through the perimeter
of the slab. In most sections of the country,
insulating the exterior edge of the slab can
reduce winter heating bills by 10 to 20 percent.
In climates with mild winters, slab insulation in
a typical 1,800 square-foot home would save
$50 to $60 annually. R-10 slab insulation for
an 1,800 square-foot home would typically
cost $300 to $600 to install. Thus, the insulation would pay for itself in 5 to 10 years.
The investment in slab insulation is also
economical when it is part of the mortgage. An
insulation cost of $450 would add about $38
to the annual mortgage. Since the insulation
saves over $50 per year on energy bills,
savings exceed the extra mortgage costs and
the investment in slab insulation pays off from
the beginning.
Slab insulation is important not only to save on
energy bills, but also to improve comfort. Cold
concrete slabs are one of the most notorious
sources of discomfort in a home. Installing
slab insulation around the perimeter of the slab
will reduce heat loss and make the slab easier
to heat. An insulated slab also provides
thermal mass to store heat and moderates
indoor temperatures.
Printed with a renewable-source ink on paper containing at
least 50% wastepaper, including 20% postconsumer waste.
December 2000
DOE/GO102000-0775
Sheet
SLAB INSULATION
THESE GUIDELINES TO OFFSET
TERMITE PROBLEMS:
•
Fact
OFFICE OF BUILDING TECHNOLOGY, STATE AND COMMUNITY PROGRAMS
ENERGY EFFICIENCY AND RENEWABLE ENERGY • U.S. DEPARTMENT OF ENERGY
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