Air Sealing Tips For the Home

Air sealing is a low cost, do it yourself project that can save you up to 20% on your heating and cooling costs according to the Environmental Protection Agency. Some homeowners are concerned with making the home to tight. This is unlikely in an older home. If you are concerned with the air quality, hire a home energy rater to test your home.

We will start in the attic and work our way down the house and to the exterior.

Attic

Seal penetrations in the wall plates -- Move back the insulation enough to expose the wall plates. Seal around wires and pipes with caulk or spray foam such as Great Stuff. This is a good place to use a fire rated caulk or foam product. In most areas it is required for new construction. Check with your local code official. Caulk both sides of the wall plate where it meets the drywall or plaster with latex caulk.

Chases should be properly sealed off and were almost always left open in older homes allowing air to easily pass though. Use plywood or drywall to cap off the chase. Cut around wires and pipes as close as possible and seal the remaining voids with caulk or spray foam.

Attic hatches - These are often a big loss of air in the home. Install an attic tent or build a box out of foam insulation board to cover the hatch. The high r foam with a foil face works the best. Use a foil face mechanical tape to hold the box together. Do not use duct tape. It will come apart in time. Also use a foam weatherstrip around the hatch door when possible. If your home has a whole house fan, build a box for it too when its not in use.

Living Space

Electrical boxes -- Caulk switch and receptacle boxes. Turn off the circuit breaker and test to be sure the power is off. Remove the wall plate with a screwdriver and caulk between the box and the drywall with latex caulk. Install a foam weatherstrip gasket and replace the wall plate. Use a damp rag to clean up any excess caulk from the wall. Turn the circuit breaker back on.

Plumbing pipes -- Check under all sinks where the pipes go through the wall. Slide back the escutcheons (trim plate) and seal around the water and drain pipes with caulk or spray foam.

Heating and cooling registers -- Remove the grill with a screwdriver and caulk or spray foam between the duct work and the drywall or flooring material. Replace the grill.

Dryer vent -- Caulk or spray foam between the metal pipe and the drywall.

Basement/Crawlspace

Seal penetrations in wall plates -- Same as in the attic.

Chases -- Same as in the attic.

Sill plates -- Seal where the sill plate meets the foundation with caulk or spray foam.

Exterior

Seal penetrations in the siding -- Caulk around electrical wires and conduits, hose bibs and air conditioning line sets with a good quality siding or window and door caulk.

Windows and doors - Inspect around windows and doors for breaks in the caulking. Use a good quality latex or window and door caulk.

Caulking

Latex -- water clean up, paintable, usually white or clear.

Silicone -- difficult to clean up, usually not paintable, comes in white, clear, brown and other colors.

Fire retardant -- use at fire stopping locations such as sealing penetrations in wall plates or chases.

Spray Foams

Standard -- great for sealing voids around pipes and wires.

Window and door -- less expansion, prevents binding of windows and doors due to the foam over expanding and pressing on the jambs. Install a fire rated windows.

Fire retardant -- use at fire stopping locations such as sealing penetrations in wall plates or chases.

Spray foams can be messy! Use caution when applying. Allow it several hours to cure before trimming away excess. Very stick until cured.

Do not seal: weep holes (in brick and windows and doors including storm windows), the bottom edge of lap siding, attic or foundation vents.