How To Pass A Blower Door Test

A large house will leak more than a small one because it has more space exposed to the outdoors. We enter building specific information when calculating the results of a blower door test. The test measures the ACH or (air changes per hour) of the home. ACH or (air changes per hour) is the number of times air will escape the home and be replaced with new air in an hour. The International Energy Conservation Codes places Philadelphia is in climate zone 4. In order to pass a blower door test in Philadelphia you will need a score that is less than 3 ACH or (air changes per hour). However, Pennsylvania has amended this law to allow up to 5 ACH or (air changes per hour).

How to pass a blower door test:

  • Anticipate potential air leaks ahead of time.
  • Using the correct outside air barrier such as Tyvek or Zip Sheathing and making sure to tape the joints.
  • Insulate the home using the correct R Value and properly install the insulation material.
  • Ensure any penetration in the exterior of the home are caulked or use spray foam.
  • Doors and windows are property installed, caulked and weather sealed.
  • Penetration between conditioned and unconditioned areas such as basements, attics and crawl spaces are sealed.
  • Philadelphia provides a step by step checklist you can follow to make sure everything is done correctly. The sheet is below or you ou can download and print it by clicking here.