The Basics of Blower Door Testing

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In its most basic form, blower door testing is a reliable method for determining the air tightness of a home and is generally performed as part of an energy audit. At Polk County Insulation, we encourage you to keep reading to find out more about the benefits of this process, how it works, and how you can prepare for blower door testing in your home.

The Basics of Blower Door Testing

Reasons to Schedule Blower Door Testing

  • Reduce the amount of energy your home consumes in every season due to air leakage.
  • Prevent moisture and condensation that can lead to damage within your home’s structure and building materials.
  • Avoid draftiness in the winter caused by cold air coming into your home through gaps in your doors and windows.
  • Gain a better understanding of how much mechanical ventilation your home needs to maintain proper indoor air quality.

The Basics of Blower Door Testing

How the Process Works

  • A powerful fan is mounted onto the frame of the exterior door, which then pulls air out of the house and lowers the interior air pressure.
  • The air pressure from the outside, which is higher, is pulled into the home through any unsealed openings and cracks.
  • Depending on the testing process, the energy auditor may use a smoke pencil to figure out the exact location of any air leaks.

Getting Ready for Blower Door Testing

  • Locate any areas of your home that are drafty or have a difficult time retaining a specific temperature, and be prepared to indicate these to the auditor.
  • Make sure the auditor can access all areas of your home, including your crawlspace, attic, closets, and built-in cabinets.
  • Plan for the test to take about an hour and expect to do a walk-through of your home with the auditor before and after blower door testing.