What’s a Blower Door Test?

What’s a Blower Door Test?

This post is the second in our series featuring information about home energy assessments, and what’s involved in the process.

One of the diagnostic tools in a professional auditor’s tool belt is a blower door test. A blower door test tells the auditor generally how airtight your home is, and identifies small holes and cracks in your home. And since these little openings can account for 30-50% of energy waste, it can be helpful to your wallet to seal them!

To help you better understand the process necessary to conduct a blower door test, here’s a few things you’ll need to know: 

  • A blower door is a powerful fan mounted into the frame of an exterior door in your home. The fan pulls all of your air out of the house, lowering the air pressure inside.
  • As this drop in air pressure occurs, the higher air pressure outside rushes into the home through any unsealed cracks, holes and openings.
  • The auditor then measures the air flowing through the blower door, which determines the severity of your home’s air leaks.  The airflow through the blower door is measured in cubic feet per minute at 50 pascals of pressure (a pascal is a small unit of air pressure). Some auditors also use a smoke puffer to visually detect air leaks.

After the auditor conducts the blower door test, she or he should provide you with a list of problem areas and how to address them. Then, it’s time to get to work sealing those cracks and openings!

Caulking and weather stripping are two cost-effective, do-it-yourself projects that will help you eliminate energy waste and reduce your utility bills with the investment of a few bucks and a little time.

If you want to identify air leaks around your home without a professional, get started with these DIY tips for locating air leaks.

For other tips and information on how to make your home more energy efficient, visit our home energy check list.

For more information check this page.