yyyy yyyy yyyy yyyy yyyy yyyy 

  yyyyyyy

yyyyyyy yyyyyyy

   yyy yyy yyy  yyy

yyy

 yyy  yyy

yyy

3 yyy

9

1

6"

or more

2

4

6

7

5

8

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, appliancestandards, and guidelines forefficient energy use

• Provides support and grants

to states and communitiesfor deployment of energyefficient technologies andpractices

WATER-MANAGED CRAWLSPACEFOUNDATION

A properly sealed, moisture-protected, andinsulated crawlspace will increase comfort,save on energy costs, improve the durability ofthe home, and reduce entry of moisture, radon,and other potential irritants or pollutants intothe home. Whichever design is followed, thekeys to an effective crawlspace are:Moisture control – using a water-managedfoundation system to drain rainwater andgroundwater away from foundations.Airtight construction – sealing all air leaksbetween the conditioned space and the outsideprior to insulation installation.Complete insulation coverage – properlyinstalling the correct insulation levels andmaking sure the insulation coverage iscontinuous and complete.WATER-MANAGED FOUNDATION SYSTEMA crawlspace is susceptible to moisture anddeterioration problems because of contact withthe earth. The best approaches for preventingthese problems will depend on the local climateand style of construction, but the followinggeneral rules apply to most crawlspace designs.1. Keep all untreated wood materials away from

the earth.

2. Provide rain drainage, such as gutters, to

conduct rainwater away from the house.

3. Slope the earth away from the house for at

least 5 feet at a minimum 5% grade (3 inchesin 5 feet). Establish drainage swales to directrainwater around the house.

4. Add a sill gasket to provide air sealing.OFFICE OF BUILDING TECHNOLOGY, STATE AND COMMUNITY PROGRAMSENERGY EFFICIENCY AND RENEWABLE ENERGY • U.S. DEPARTMENT OF ENERGY

5. Install a protective membrane, such as an

EPDM-type membrane, to serve as a capillarybreak that reduces wicking of water from themasonry wall. This membrane, in addition tometal flashing, can serve as a termite shield.

6. Dampproof the below-grade portion of the

foundation wall to prevent the wall fromabsorbing ground moisture by capillary action.

7. Install drainage plane material or gravel

against the foundation wall to relievehydrostatic pressure and channel water tothe foundation drain.

8. Provide a foundation drainage system at the

bottom of the footing, not on top, when thefoundation floor (interior grade) is below theexterior grade. Surround a perforated 4-inch drainpipe with gravel and cover them with filter fabric.

9. Install 6-mil polyethylene across the

crawlspace floor to prevent soil moisture frommigrating into the crawlspace. Overlap andtape all seams by 12 inches, and seal thepolyethylene 6 inches up the crawlspace walls.

 sealed, continuous layer of 6-mil

ylene over the crawlspace floor.

 plastic tee below the polyethylene

trudes through the polyethylene.

vertical 3-inch plastic pipe from the

on to the roof through an interior wall.

t the tee to the vertical 3-inch plastic

 passive mitigation.

 electrician stub-in a junction box in

c.

 bottom conditioned room for radon

EPA-listed radon test kit, or hire a

d technician. If the house has a high

oncentration, install an active radon

on system by attaching a small

to the plastic pipe in the attic to expel

es to the outside.

levels are especially high (over 25 pico

er liter), consult with local radon experts.

Electrical junction box

Plastic vent stack

Sealedpolyethylene 

Perforated "T" fitting

Optional blower(if required)

RESISTANT

RUCTION
Metal staves

support insulation –engineered I-beams require a longer stave

wlspace must be located inside the

r unless an airtight, insulated ac

 wall is built and maintained.

G CRAWLSPACE WALL

od of foundation insulation with pest

fficials to ensure code compliance.

dation vents.

rnaces and water heaters located in

combustion units equipped with a

em.

he exterior wall during and after

e band joist.

    yy yy yy yy 

s embedded in gravel, 

nd located at lower perimeter 

vide drainage.

6-mil poly vapor diffusion retarder

R-11 to R-19 batt insulation

    yyyy yyyy yyyy yyyy 

   yyy yyy yyy

  yyyy yyyy

brane 

e of 

es 

e

Protective membrane overlaps and extends down underneath insulation to footing 

Unfaced insulation in band joist

Sill gasket

Option 3Interior battinsulation

joist being insulated and slit to fit around wiring and plumbing.Insulate the band joist area between air ducts and the floor asspace permits. Use insulation hangers (wire staves) spaced every12-18 inches to hold the floor insulation in place without compressing the insulation more than 1 inch.

5. The orientation of the vapor barrier depends on the home’s

location. In most of the country, the vapor barrier should faceupward. However, in certain regions of the Gulf states andother areas with mild winters and hot summers, it should facedownward.

6. Insulate all ductwork in the crawlspace.7. Insulate all hot and cold water lines in the crawlspace unless

they are located within the insulation.

8. Close crawlspace vents after making sure the crawlspace is dry

and all construction materials have dried out.

accessed from the Internet at www.ornl.gov/roofs+walls.

7. Install rigid or batt insulation using one of three options

(exterior foam, interior foam, or interior batt) to achieve complete insulation coverage. Insulate the band joist with batt insulation, and the crawlspace access if it is located in the wall.Install a continuous termite shield between the band joist andmasonry foundation wall that covers the wall insulation andextends completely outside, or leave a 2- to 4-inch insulationgap at the top for termite inspection.

8. Install a supply outlet in the crawlspace, relying on the

leakiness of the floor to provide the return air path.

STEPS FOR INSTALLING UNDERFLOORINSULATION1. During the early phases of construction, meet with the

mechanical subcontractors (plumbing, electrical, and heating/cooling) to inform them of the importance of keeping thespace between floor joists as clear as possible. Run drainlines, electrical wiring, and ductwork below the bottom of theinsulation so that a continuous layer of insulation can beinstalled. For protection against freezing, supply plumbingmay be located within the insulation. The best approach is torun supply plumbing together in a few joist spaces. Theinsulation can be split and run around the piping.

2. Seal all air leaks between the conditioned area of the home

and the crawlspace. High-priority leaks include holes aroundbathtub drains and other drain lines, plenums for ductwork,and penetrations for electrical wiring, plumbing, and ductwork(including duct boot connections at the floor).

3. Select insulation levels in accordance with the International

Energy Conservation Code or the DOE Insulation Fact Sheet.

4. Insulation batts with an attached vapor barrier are usually used to

insulate framed floors. Obtain insulation with the proper width forthe joist spacing of the floor being insulated. Complete coverageis essential 

– leave no insulation voids. The batts should be

installed flush against the subfloor to eliminate any gaps that mayserve as passageways for cold air to flow between the insulationand the subfloor. The batts should be cut to the full length of the

INSULATING TRUSS FLOOR SYSTEMSInstead of batt insulation, a better approach is toinstall netting or rigid insulation to the undersideof the floor trusses and filling the space createdbetween the netting or insulation and subfloorwith a loose-fill insulation.

aaa

aaaaaaaaaaaaaaaaaaaaaaaaaaaa     @@@@@ @@@@@ @@@@@ @@@@@     ÀÀÀÀÀ ÀÀÀÀÀ ÀÀÀÀÀ ÀÀÀÀÀ     @@@@@ @@@@@ @@@@@ @@@@@     ÀÀÀÀÀ ÀÀÀÀÀ ÀÀÀÀÀ ÀÀÀÀÀ     @@@@@ @@@@@ @@@@@ @@@@@     ÀÀÀÀÀ ÀÀÀÀÀ ÀÀÀÀÀ ÀÀÀÀÀ     @@@@@ @@@@@ @@@@@ @@@@@     ÀÀÀÀÀ ÀÀÀÀÀ ÀÀÀÀÀ ÀÀÀÀÀ     @@@@@ @@@@@ @@@@@ @@@@@     ÀÀÀÀÀ ÀÀÀÀÀ ÀÀÀÀÀ ÀÀÀÀÀ     @@@@@ @@@@@ @@@@@ @@@@@     ÀÀÀÀÀ ÀÀÀÀÀ ÀÀÀÀÀ ÀÀÀÀÀ     @@@@@ @@@@@ @@@@@ @@@@@     ÀÀÀÀÀ ÀÀÀÀÀ ÀÀÀÀÀ ÀÀÀÀÀ     yyyyy yyyyy yyyyy yyyyy    yyyy yyyy yyyy yyyy Inexpensive landscape cloth stapled to webs support insulation    @@@ @@@ @@@    ÀÀÀ ÀÀÀ ÀÀÀ    @@@ @@@ @@@    ÀÀÀ ÀÀÀ ÀÀÀ    @@@ @@@ @@@    ÀÀÀ ÀÀÀ ÀÀÀ    @@@ @@@ @@@    ÀÀÀ ÀÀÀ ÀÀÀ    @@@ @@@ @@@    ÀÀÀ ÀÀÀ ÀÀÀ    @@@ @@@ @@@    ÀÀÀ ÀÀÀ ÀÀÀ    @@@ @@@ @@@    ÀÀÀ ÀÀÀ ÀÀÀ    yyy yyy yyy    @@@ @@@ @@@    ÀÀÀ ÀÀÀ ÀÀÀ    @@@ @@@ @@@    ÀÀÀ ÀÀÀ ÀÀÀ    @@@ @@@ @@@    ÀÀÀ ÀÀÀ ÀÀÀ    @@@ @@@ @@@    ÀÀÀ ÀÀÀ ÀÀÀ    @@@ @@@ @@@    ÀÀÀ ÀÀÀ ÀÀÀ    @@@ @@@ @@@    ÀÀÀ ÀÀÀ ÀÀÀ    @@@ @@@ @@@    ÀÀÀ ÀÀÀ ÀÀÀ    yyy yyy yyy Loose-fill insulation fills gaps between trusses and is contained by landscape cloth attached to truss members
Metal staves

support insulation –engineered I-beams require a longer stave

wlspace must be located inside the

r unless an airtight, insulated ac

 wall is built and maintained.

G CRAWLSPACE WALL

od of foundation insulation with pest

fficials to ensure code compliance.

dation vents.

rnaces and water heaters located in

combustion units equipped with a

em.

he exterior wall during and after

e band joist.

    yy yy yy yy 

s embedded in gravel, 

nd located at lower perimeter 

vide drainage.

6-mil poly vapor diffusion retarder

R-11 to R-19 batt insulation

    yyyy yyyy yyyy yyyy 

   yyy yyy yyy

  yyyy yyyy

brane 

e of 

es 

e

Protective membrane overlaps and extends down underneath insulation to footing 

Unfaced insulation in band joist

Sill gasket

Option 3Interior battinsulation

joist being insulated and slit to fit around wiring and plumbing.Insulate the band joist area between air ducts and the floor asspace permits. Use insulation hangers (wire staves) spaced every12-18 inches to hold the floor insulation in place without compressing the insulation more than 1 inch.

5. The orientation of the vapor barrier depends on the home’s

location. In most of the country, the vapor barrier should faceupward. However, in certain regions of the Gulf states andother areas with mild winters and hot summers, it should facedownward.

6. Insulate all ductwork in the crawlspace.7. Insulate all hot and cold water lines in the crawlspace unless

they are located within the insulation.

8. Close crawlspace vents after making sure the crawlspace is dry

and all construction materials have dried out.

accessed from the Internet at www.ornl.gov/roofs+walls.

7. Install rigid or batt insulation using one of three options

(exterior foam, interior foam, or interior batt) to achieve complete insulation coverage. Insulate the band joist with batt insulation, and the crawlspace access if it is located in the wall.Install a continuous termite shield between the band joist andmasonry foundation wall that covers the wall insulation andextends completely outside, or leave a 2- to 4-inch insulationgap at the top for termite inspection.

8. Install a supply outlet in the crawlspace, relying on the

leakiness of the floor to provide the return air path.

STEPS FOR INSTALLING UNDERFLOORINSULATION1. During the early phases of construction, meet with the

mechanical subcontractors (plumbing, electrical, and heating/cooling) to inform them of the importance of keeping thespace between floor joists as clear as possible. Run drainlines, electrical wiring, and ductwork below the bottom of theinsulation so that a continuous layer of insulation can beinstalled. For protection against freezing, supply plumbingmay be located within the insulation. The best approach is torun supply plumbing together in a few joist spaces. Theinsulation can be split and run around the piping.

2. Seal all air leaks between the conditioned area of the home

and the crawlspace. High-priority leaks include holes aroundbathtub drains and other drain lines, plenums for ductwork,and penetrations for electrical wiring, plumbing, and ductwork(including duct boot connections at the floor).

3. Select insulation levels in accordance with the International

Energy Conservation Code or the DOE Insulation Fact Sheet.

4. Insulation batts with an attached vapor barrier are usually used to

insulate framed floors. Obtain insulation with the proper width forthe joist spacing of the floor being insulated. Complete coverageis essential 

– leave no insulation voids. The batts should be

installed flush against the subfloor to eliminate any gaps that mayserve as passageways for cold air to flow between the insulationand the subfloor. The batts should be cut to the full length of the

INSULATING TRUSS FLOOR SYSTEMSInstead of batt insulation, a better approach is toinstall netting or rigid insulation to the undersideof the floor trusses and filling the space createdbetween the netting or insulation and subfloorwith a loose-fill insulation.

aaa

aaaaaaaaaaaaaaaaaaaaaaaaaaaa     @@@@@ @@@@@ @@@@@ @@@@@     ÀÀÀÀÀ ÀÀÀÀÀ ÀÀÀÀÀ ÀÀÀÀÀ     @@@@@ @@@@@ @@@@@ @@@@@     ÀÀÀÀÀ ÀÀÀÀÀ ÀÀÀÀÀ ÀÀÀÀÀ     @@@@@ @@@@@ @@@@@ @@@@@     ÀÀÀÀÀ ÀÀÀÀÀ ÀÀÀÀÀ ÀÀÀÀÀ     @@@@@ @@@@@ @@@@@ @@@@@     ÀÀÀÀÀ ÀÀÀÀÀ ÀÀÀÀÀ ÀÀÀÀÀ     @@@@@ @@@@@ @@@@@ @@@@@     ÀÀÀÀÀ ÀÀÀÀÀ ÀÀÀÀÀ ÀÀÀÀÀ     @@@@@ @@@@@ @@@@@ @@@@@     ÀÀÀÀÀ ÀÀÀÀÀ ÀÀÀÀÀ ÀÀÀÀÀ     @@@@@ @@@@@ @@@@@ @@@@@     ÀÀÀÀÀ ÀÀÀÀÀ ÀÀÀÀÀ ÀÀÀÀÀ     yyyyy yyyyy yyyyy yyyyy    yyyy yyyy yyyy yyyy Inexpensive landscape cloth stapled to webs support insulation    @@@ @@@ @@@    ÀÀÀ ÀÀÀ ÀÀÀ    @@@ @@@ @@@    ÀÀÀ ÀÀÀ ÀÀÀ    @@@ @@@ @@@    ÀÀÀ ÀÀÀ ÀÀÀ    @@@ @@@ @@@    ÀÀÀ ÀÀÀ ÀÀÀ    @@@ @@@ @@@    ÀÀÀ ÀÀÀ ÀÀÀ    @@@ @@@ @@@    ÀÀÀ ÀÀÀ ÀÀÀ    @@@ @@@ @@@    ÀÀÀ ÀÀÀ ÀÀÀ    yyy yyy yyy    @@@ @@@ @@@    ÀÀÀ ÀÀÀ ÀÀÀ    @@@ @@@ @@@    ÀÀÀ ÀÀÀ ÀÀÀ    @@@ @@@ @@@    ÀÀÀ ÀÀÀ ÀÀÀ    @@@ @@@ @@@    ÀÀÀ ÀÀÀ ÀÀÀ    @@@ @@@ @@@    ÀÀÀ ÀÀÀ ÀÀÀ    @@@ @@@ @@@    ÀÀÀ ÀÀÀ ÀÀÀ    @@@ @@@ @@@    ÀÀÀ ÀÀÀ ÀÀÀ    yyy yyy yyy Loose-fill insulation fills gaps between trusses and is contained by landscape cloth attached to truss members
      yyyy yyyy yyyy yyyy yyyy yyyy 

  yyyyyyy

yyyyyyy yyyyyyy

   yyy yyy yyy  yyy

yyy

 yyy  yyy

yyy

3 yyy

9

1

6"

or more

2

4

6

7

5

8

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, appliancestandards, and guidelines forefficient energy use

• Provides support and grants

to states and communitiesfor deployment of energyefficient technologies andpractices

WATER-MANAGED CRAWLSPACEFOUNDATION

A properly sealed, moisture-protected, andinsulated crawlspace will increase comfort,save on energy costs, improve the durability ofthe home, and reduce entry of moisture, radon,and other potential irritants or pollutants intothe home. Whichever design is followed, thekeys to an effective crawlspace are:Moisture control – using a water-managedfoundation system to drain rainwater andgroundwater away from foundations.Airtight construction – sealing all air leaksbetween the conditioned space and the outsideprior to insulation installation.Complete insulation coverage – properlyinstalling the correct insulation levels andmaking sure the insulation coverage iscontinuous and complete.WATER-MANAGED FOUNDATION SYSTEMA crawlspace is susceptible to moisture anddeterioration problems because of contact withthe earth. The best approaches for preventingthese problems will depend on the local climateand style of construction, but the followinggeneral rules apply to most crawlspace designs.1. Keep all untreated wood materials away from

the earth.

2. Provide rain drainage, such as gutters, to

conduct rainwater away from the house.

3. Slope the earth away from the house for at

least 5 feet at a minimum 5% grade (3 inchesin 5 feet). Establish drainage swales to directrainwater around the house.

4. Add a sill gasket to provide air sealing.OFFICE OF BUILDING TECHNOLOGY, STATE AND COMMUNITY PROGRAMSENERGY EFFICIENCY AND RENEWABLE ENERGY • U.S. DEPARTMENT OF ENERGY

5. Install a protective membrane, such as an

EPDM-type membrane, to serve as a capillarybreak that reduces wicking of water from themasonry wall. This membrane, in addition tometal flashing, can serve as a termite shield.

6. Dampproof the below-grade portion of the

foundation wall to prevent the wall fromabsorbing ground moisture by capillary action.

7. Install drainage plane material or gravel

against the foundation wall to relievehydrostatic pressure and channel water tothe foundation drain.

8. Provide a foundation drainage system at the

bottom of the footing, not on top, when thefoundation floor (interior grade) is below theexterior grade. Surround a perforated 4-inch drainpipe with gravel and cover them with filter fabric.

9. Install 6-mil polyethylene across the

crawlspace floor to prevent soil moisture frommigrating into the crawlspace. Overlap andtape all seams by 12 inches, and seal thepolyethylene 6 inches up the crawlspace walls.

 sealed, continuous layer of 6-mil

ylene over the crawlspace floor.

 plastic tee below the polyethylene

trudes through the polyethylene.

 vertical 3-inch plastic pipe from the

on to the roof through an interior wall.

t the tee to the vertical 3-inch plastic

 passive mitigation.

 electrician stub-in a junction box in

c.

e bottom conditioned room for radon

EPA-listed radon test kit, or hire a

d technician. If the house has a high

oncentration, install an active radon

on system by attaching a small

to the plastic pipe in the attic to expel

es to the outside.

 levels are especially high (over 25 pico

er liter), consult with local radon experts.

Electrical junction box

Plastic vent stack

Sealedpolyethylene 

Perforated "T" fitting

Optional blower(if required)

RESISTANT

RUCTION