What is the Blower Door Test?
The Blower Door Test (BDT) measures the amount of air needed to keep a house at an elevated pressure of 50 Pascal. This depressurization of air essentially amplifies a home’s air leaks making it easier to measure them. The BDT measures leaks that may come from a variety of areas. The most common places where homeowners will find air leaks are:
- Fireplace Flues
When a Blower Door Test is performed, all doors, windows, vents, and flues must be closed as much as possible. An infrared camera can be used as a visual to see the leaks. Air leaks, insulation voids, and moisture damage will typically show blue on an infrared screen.
How Can Contractors Use Them?
Even with today’s technology, there is still no such thing as a perfectly airtight house. Michigan recently adopted the 2015 edition of the International Energy Conservation Code (IECC). As part of the 2015 code, Michigan builders are required to complete a BDT on all new residential constructions. To avoid conflict of interest, builders and contractors are not permitted to perform their own BDT’s and must hire an independent third party to complete the testing. The average cost is between $250- $450 USD.
Where Can I Find This in The 2015 Code Book?
On page 447, Michigan Energy Code N1188.8.131.52 of the 2015 Michigan Residential Code book states that, “The building or dwelling unit shall be tested and verified as having an air leakage rate not exceeding 4 air changes per hour. Testing shall be conducted with a blower door at a pressure of 0.2 inches w.g. (50 Pascals).” The Energy Code (Chapter 11) also states that Code Officials require that “testing shall be conducted by a certified third party” (pg. 448).