" "We must not, in trying to think about how we can make a big difference, ignore the small daily differences we can make which, over time, add up to big differences that we often cannot foresee." " -- Marian Wright Edelman

Blower Door Tests

Professional energy auditors use blower door tests to help determine a home's airtightness, this powerful tool helps homeowners to:

  • Reduce energy consumption due to air leakage
  • Avoid moisture condensation problems in walls
  • Avoid uncomfortable drafts caused by cold air leaking in from the outdoors

How They Work

A blower door is a variable speed fan that mounts into a frame and flexile panel of an exterior door. The fan, which is hooked up to pressure and airflow gauges, pulls air out of the house, lowering the air pressure inside. The higher outside air pressure then flows into the house through all unsealed cracks and openings. The auditors uses a smoking device to detect these air leaks many of which can be easily sealed using caulk and foam. The data collected during this test can be used to determine the air infiltration rate of your home.

Preparing for a Blower Door Test

Take the following steps to prepare your home for a blower door test:

  • Close windows and open interior doors
  • Turn down the thermostats on heaters and water heaters
  • Cover ashes in wood stoves and fireplaces with damp newspapers
  • Shut fireplace dampers, fireplace doors, and wood stove air intakes.