Home Air Leakage

A certified BPI Building Analyst will perform what is called a blower door test to check the areas of leakage within your home and the envelope of your home.  

A blower door is a powerful fan mounted unit that we will install in your main doorway. It works by depressurizing your home (blowing the air out of the house to temporarily lower the air pressure inside). The pressure of the outdoor air causes the air to flow into the house through all unsealed openings, revealing any undetected leaks.  

Our Building Analyst will perform a complete walk through of your home during this test using a smoke pen as needed to detect leaks and determine the total air infiltration rate of your home.  

How to Prepare for a Blower Door Test:

• Make a list of areas in your home that you believe to be drafty or possible areas that leakage may be detected
• If you have a fireplace, remove any ashes or debris from your fireplace prior to the testing
• Make sure all exterior doors and windows are closed

• Caulk and weatherstrip doors and windows that leak air
• Caulk and seal air leaks where plumbing, ducting, or electrical wiring comes through walls, floors, ceilings and soffits over cabinets
• Install foam gaskets behind outlet and switch plates on walls
• Inspect dirty spots in your insulation for air leaks and mold and seal leaks with low-expansion spray foam made for this purpose and install house flashing if needed
• Look for dirty spots on your ceiling paint and carpet, which may indicate air leaks at interior wall/ceiling joints and wall/floor joists, and caulk them
• Cover single-pane windows with storm windows or replace them with more efficient dual pane windows
• Use foam sealant on larger gaps around windows, baseboards and other places where air may leak out.
• Cover your kitchen exhaust fan to stop air leaks when not in use
• Check your dryer vent to be sure it is not blocked (this will save energy and may prevent a fire)
• Replace door bottoms and thresholds with ones that have sealing gaskets
• Keep the fireplace flue damper tightly closed when not in use
• Seal air leaks around fireplace chimneys, furnaces and gas-fired water heater vents with fire-resistant materials such as sheet metal or sheetrock and furnace cement caulk