OFFICE OF BUILDING TECHNOLOGY, STATE AND COMMUNITY PROGRAMSENERGY EFFICIENCY AND RENEWABLE ENERGY • U.S. DEPARTMENT OF ENERGY

Buildings forthe 21st CenturyBuildings that are moreenergy efficient, comfortable,and affordable...that’s thegoal of DOE’s Office of BuildingTechnology, State andCommunity Programs (BTS).To accelerate the developmentand wide application of energyefficiency measures, BTS:• Conducts R&D on technologies

and concepts for energy efficiency, working closely withthe building industry and withmanufacturers of materials,equipment, and appliances

• Promotes energy/money

saving opportunities to bothbuilders and buyers of homesand commercial buildings

• Works with state and local

regulatory groups to improvebuilding codes, appliance standards, and guidelines for efficient energy use

• Provides support and grants

to states and communitiesfor deployment of energyefficient technologies andpractices

Slab-on-grade floors are often the least expensive foundation system and can expedite theconstruction process. The foundation consistsof a concrete slab poured over at least 4 inchesof gravel and a layer of 10-mil polyethylene.Virtually any floor covering works well with aslab, although wood flooring systems mayrequire installation of wooden furring stripsprior 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 thefloor in a daylight basement—where the floorlevel is about even with outside earth. Areaswith mild winters do not require a deep foundation.In these regions, slab-on-grade foundations mayprove an ideal choice for flat lots.Care must be taken in designing a home with aslab foundation to avoid a “squat” appearance.For example, porches are at grade level inhouses with a slab foundation, rather thanbeing elevated above the yard. The hardsurface of the slab foundation may causeinjuries, more frequent breakage of droppedobjects, and tired feet unless it is covered withcarpeting or other softer floor finishes. Use ofslab foundations can also make it more difficultto install wiring, plumbing, and ductwork, sothe design of these systems into theconstruction plans and process is essential.BENEFITS OF INSULATINGSLAB-ON-GRADE FLOORSSlabs lose energy primarily as a result of heatconducted outward and through the perimeterof the slab. In most sections of the country,insulating the exterior edge of the slab canreduce winter heating bills by 10 to 20 percent.

In climates with mild winters, slab insulation ina typical 1,800 square-foot home would save$50 to $60 annually. R-10 slab insulation foran 1,800 square-foot home would typicallycost $300 to $600 to install. Thus, the insulation would pay for itself in 5 to 10 years.The investment in slab insulation is alsoeconomical when it is part of the mortgage. Aninsulation cost of $450 would add about $38to the annual mortgage. Since the insulationsaves over $50 per year on energy bills,savings exceed the extra mortgage costs andthe investment in slab insulation pays off fromthe beginning.Slab insulation is important not only to save onenergy bills, but also to improve comfort. Coldconcrete slabs are one of the most notorioussources of discomfort in a home. Installingslab insulation around the perimeter of the slabwill reduce heat loss and make the slab easierto heat. An insulated slab also providesthermal mass to store heat and moderatesindoor temperatures.

Provides a thermal break to the perimeterof slab-on-grade foundations.

 effective, the termite shield may deter

 widespread infestation and may also

rmites into an exposed area where they

detected. It should project beyond the

e and all other portions of the exterior

continuous layer of a membrane such

erized roofing material used in

rcial buildings may be used as an

ve to the termite shield.

oam insulation with a termiticide.

 a derivative of boric acid, the

ide should pose no more threat to

wners than traditional termite

nts. One of the nation’s leading foam

on manufacturers is planning to offer

e-treated insulation board on the

in the year 2000 or 2001.
hes in 5 feet). Establish drainage

 rainwater around the house.

e between the slab and bottom plate

ane (such as rubberized roofing

tion membranes) to serve as a

s wicking of water up from the

ne can also serve as a termite shield.

directly beside the bottom of the

rain assembly includes a filter

ated plastic drain pipe typically

ate the drain beside the footing, not

wing against the seam between the

 wall and prevent wicking from a

tem wall.

d moisture barrier under the slab

 of 10-mil polyethylene placed over

sulation with pest control and local

 code compliance.

ccordance with the International

 (IECC) or DOE Insulation Fact

 Sheet (DOE/CE-0180) can be

fficiency and Renewable Energy

 from the Internet at

.

g one of the two general designs

e insulation coverage of the slab

tion approved for below-grade use.

4. If insulation is installed on the exterior of the slab:

• The insulation should be installed from the top of the slab

to the bottom of the frost line unless a termite inspectiongap is required.

• Encapsulate or cover the exterior face of the insulation

with a protective membrane to serve as a capillary breakand to protect the insulation from termites.

• Cover the above-grade portion of the insulation exposed

to outside air using a stucco coating, pressure-treatedwood, brick, or aluminum flashing. When coveringinsulation, be conscious of how to detect termites in areasprone to termite infestation. Some states in termite-proneareas have addressed this issue by requiring a termiteinspection gap near the top of the slab insulation.

• 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 thehouse has a high radon concentration, install an active radonmitigation system by attaching a small blower to the plasticpipe 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-RESISTANTCONSTRUCTIONPassiveradon-resistantconstruction is aninexpensive firstcost. It can easily beupgraded if activemitigation is laterrequired to cure aradon problem.

Electrical junction box

Plastic vent stack

Sealedpolyethylene 

Perforated "T" fitting

Optional blower(if required)

  @@@@@@@@@@@@@@ @@@@@@@@@@@@@@   ÀÀÀÀÀÀÀÀÀÀÀÀÀÀ ÀÀÀÀÀÀÀÀÀÀÀÀÀÀ   @@@@@@@@@@@@@@ @@@@@@@@@@@@@@   ÀÀÀÀÀÀÀÀÀÀÀÀÀÀ ÀÀÀÀÀÀÀÀÀÀÀÀÀÀ   @@@@@@@@@@@@@@ @@@@@@@@@@@@@@   ÀÀÀÀÀÀÀÀÀÀÀÀÀÀ ÀÀÀÀÀÀÀÀÀÀÀÀÀÀ   @@@@@@@@@@@@@@ @@@@@@@@@@@@@@   ÀÀÀÀÀÀÀÀÀÀÀÀÀÀ ÀÀÀÀÀÀÀÀÀÀÀÀÀÀ   @@@@@@@@@@@@@@ @@@@@@@@@@@@@@   ÀÀÀÀÀÀÀÀÀÀÀÀÀÀ ÀÀÀÀÀÀÀÀÀÀÀÀÀÀ           @@@@@@@@@@@@@@@@@@@@@@@@@@@@  ÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀ           @@@@@@@@@@@@@@@@@@@@@@@@@@@@  ÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀ           @@@@@@@@@@@@@@@@@@@@@@@@@@@@  ÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀ           @@@@@@@@@@@@@@@@@@@@@@@@@@@@  ÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀ           @@@@@@@@@@@@@@@@@@@@@@@@@@@@  ÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀ

Heating Degree Days (HDDs):Heating Feet Installed R-value ofDegree Days Vertically Slab Insulation0 to 2,499 none required2,499 to 4,500 2 feet R-44,500 to 6,000 2 feet R-56,000 to 7,200 4 feet R-67,200 to 8,700 4 feet R-78,700 to 10,000 4 feet R-810,000 to 12,400 4 feet R-912,400 to 14,000 4 feet R-10HDD=HEATING DEGREE DAYS(Consult your local weather bureau for your city’s actualannual Heating Degree Days.) Heating Degree Days is aterm used to help indicate the heating needed for anycertain day. This method is commonly used to determinefuel consumption and/or the cost of heating during aseason by using historical weather trends to calculateaverage seasonal temperatures.
hes in 5 feet). Establish drainage

 rainwater around the house.

e between the slab and bottom plate

ane (such as rubberized roofing

tion membranes) to serve as a

s wicking of water up from the

ne can also serve as a termite shield.

directly beside the bottom of the

rain assembly includes a filter

ated plastic drain pipe typically

ate the drain beside the footing, not

wing against the seam between the

 wall and prevent wicking from a

tem wall.

d moisture barrier under the slab

 of 10-mil polyethylene placed over

sulation with pest control and local

 code compliance.

ccordance with the International

 (IECC) or DOE Insulation Fact

 Sheet (DOE/CE-0180) can be

fficiency and Renewable Energy

 from the Internet at

.

g one of the two general designs

e insulation coverage of the slab

tion approved for below-grade use.

4. If insulation is installed on the exterior of the slab:

• The insulation should be installed from the top of the slab

to the bottom of the frost line unless a termite inspectiongap is required.

• Encapsulate or cover the exterior face of the insulation

with a protective membrane to serve as a capillary breakand to protect the insulation from termites.

• Cover the above-grade portion of the insulation exposed

to outside air using a stucco coating, pressure-treatedwood, brick, or aluminum flashing. When coveringinsulation, be conscious of how to detect termites in areasprone to termite infestation. Some states in termite-proneareas have addressed this issue by requiring a termiteinspection gap near the top of the slab insulation.

• 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 thehouse has a high radon concentration, install an active radonmitigation system by attaching a small blower to the plasticpipe 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-RESISTANTCONSTRUCTIONPassiveradon-resistantconstruction is aninexpensive firstcost. It can easily beupgraded if activemitigation is laterrequired to cure aradon problem.

Electrical junction box

Plastic vent stack

Sealedpolyethylene 

Perforated "T" fitting

Optional blower(if required)

  @@@@@@@@@@@@@@ @@@@@@@@@@@@@@   ÀÀÀÀÀÀÀÀÀÀÀÀÀÀ ÀÀÀÀÀÀÀÀÀÀÀÀÀÀ   @@@@@@@@@@@@@@ @@@@@@@@@@@@@@   ÀÀÀÀÀÀÀÀÀÀÀÀÀÀ ÀÀÀÀÀÀÀÀÀÀÀÀÀÀ   @@@@@@@@@@@@@@ @@@@@@@@@@@@@@   ÀÀÀÀÀÀÀÀÀÀÀÀÀÀ ÀÀÀÀÀÀÀÀÀÀÀÀÀÀ   @@@@@@@@@@@@@@ @@@@@@@@@@@@@@   ÀÀÀÀÀÀÀÀÀÀÀÀÀÀ ÀÀÀÀÀÀÀÀÀÀÀÀÀÀ   @@@@@@@@@@@@@@ @@@@@@@@@@@@@@   ÀÀÀÀÀÀÀÀÀÀÀÀÀÀ ÀÀÀÀÀÀÀÀÀÀÀÀÀÀ           @@@@@@@@@@@@@@@@@@@@@@@@@@@@  ÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀ           @@@@@@@@@@@@@@@@@@@@@@@@@@@@  ÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀ           @@@@@@@@@@@@@@@@@@@@@@@@@@@@  ÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀ           @@@@@@@@@@@@@@@@@@@@@@@@@@@@  ÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀ           @@@@@@@@@@@@@@@@@@@@@@@@@@@@  ÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀ

Heating Degree Days (HDDs):Heating Feet Installed R-value ofDegree Days Vertically Slab Insulation0 to 2,499 none required2,499 to 4,500 2 feet R-44,500 to 6,000 2 feet R-56,000 to 7,200 4 feet R-67,200 to 8,700 4 feet R-78,700 to 10,000 4 feet R-810,000 to 12,400 4 feet R-912,400 to 14,000 4 feet R-10HDD=HEATING DEGREE DAYS(Consult your local weather bureau for your city’s actualannual Heating Degree Days.) Heating Degree Days is aterm used to help indicate the heating needed for anycertain day. This method is commonly used to determinefuel consumption and/or the cost of heating during aseason by using historical weather trends to calculateaverage seasonal temperatures.
OFFICE OF BUILDING TECHNOLOGY, STATE AND COMMUNITY PROGRAMSENERGY EFFICIENCY AND RENEWABLE ENERGY • U.S. DEPARTMENT OF ENERGY

Buildings forthe 21st CenturyBuildings that are moreenergy efficient, comfortable,and affordable...that’s thegoal of DOE’s Office of BuildingTechnology, State andCommunity Programs (BTS).To accelerate the developmentand wide application of energyefficiency measures, BTS:• Conducts R&D on technologies

and concepts for energy efficiency, working closely withthe building industry and withmanufacturers of materials,equipment, and appliances

• Promotes energy/money

saving opportunities to bothbuilders and buyers of homesand commercial buildings

• Works with state and local

regulatory groups to improvebuilding codes, appliance standards, and guidelines for efficient energy use

• Provides support and grants

to states and communitiesfor deployment of energyefficient technologies andpractices

Slab-on-grade floors are often the least expensive foundation system and can expedite theconstruction process. The foundation consistsof a concrete slab poured over at least 4 inchesof gravel and a layer of 10-mil polyethylene.Virtually any floor covering works well with aslab, although wood flooring systems mayrequire installation of wooden furring stripsprior 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 thefloor in a daylight basement—where the floorlevel is about even with outside earth. Areaswith mild winters do not require a deep foundation.In these regions, slab-on-grade foundations mayprove an ideal choice for flat lots.Care must be taken in designing a home with aslab foundation to avoid a “squat” appearance.For example, porches are at grade level inhouses with a slab foundation, rather thanbeing elevated above the yard. The hardsurface of the slab foundation may causeinjuries, more frequent breakage of droppedobjects, and tired feet unless it is covered withcarpeting or other softer floor finishes. Use ofslab foundations can also make it more difficultto install wiring, plumbing, and ductwork, sothe design of these systems into theconstruction plans and process is essential.BENEFITS OF INSULATINGSLAB-ON-GRADE FLOORSSlabs lose energy primarily as a result of heatconducted outward and through the perimeterof the slab. In most sections of the country,insulating the exterior edge of the slab canreduce winter heating bills by 10 to 20 percent.

In climates with mild winters, slab insulation ina typical 1,800 square-foot home would save$50 to $60 annually. R-10 slab insulation foran 1,800 square-foot home would typicallycost $300 to $600 to install. Thus, the insulation would pay for itself in 5 to 10 years.The investment in slab insulation is alsoeconomical when it is part of the mortgage. Aninsulation cost of $450 would add about $38to the annual mortgage. Since the insulationsaves over $50 per year on energy bills,savings exceed the extra mortgage costs andthe investment in slab insulation pays off fromthe beginning.Slab insulation is important not only to save onenergy bills, but also to improve comfort. Coldconcrete slabs are one of the most notorioussources of discomfort in a home. Installingslab insulation around the perimeter of the slabwill reduce heat loss and make the slab easierto heat. An insulated slab also providesthermal mass to store heat and moderatesindoor temperatures.

Provides a thermal break to the perimeterof slab-on-grade foundations.

 effective, the termite shield may deter

 widespread infestation and may also

rmites into an exposed area where they

detected. It should project beyond the

e and all other portions of the exterior

continuous layer of a membrane such

erized roofing material used in

rcial buildings may be used as an

ve to the termite shield.

oam insulation with a termiticide.

 a derivative of boric acid, the

ide should pose no more threat to

wners than traditional termite

nts. One of the nation’s leading foam

on manufacturers is planning to offer

e-treated insulation board on the

in the year 2000 or 2001.