Blower Door Testing

Blower doors measure the air tightness of a house. most homes have air leaks, but the amount of leakage can vary greatly.the blower door is a calibrated fan that is temporarily mounted in an exterior door, It is measured through a digital manometer that calculates air flow and pressure.

The tightness of a hose is measured in three metrics

1. It measures the air flow rate at the elevated pressure measurement of 50 pascals. We calculate what the number should be and the blower door gives us the actual number
2. The blower door will also tell us how much air leakage the house is by taking all the leakage areas and put it into one number a tight house is 2" to 5" a leaky house 2'
3. The ACH ( air change per hour ) is the most important number as it stays the same no matter what size the house. the lower the ACH the more efficient and more comfortable it is.

The 2015 IECC energy code states that house's be less than 4 air changes per hour (N1102.4.1.2 of the Michigan Energy Code). For instance:

• 10 to 20 air changes- If it were a boat it would sink
• 7 to 10 air changes per hour-the house is reasonably tight but can be improved
• 4 to 7 air changes per hour-the good zone, the house is pretty tight and you typically still have good air quality.
• 1 to 3 air changes per hour- well sealed and probably should have some type of mechanical fresh air induction- ERV or HRV

We take pride in making sure our data is always accurate so the test numbers are right