Blower Door Testing on Your Home

Tuesday, May 30th, 2017 by Joy Padgett

Ok, so, today we’re going to talk about my absolute favorite piece of equipment when it comes to diagnosing issues with how a house is performing. I am so excited!! This piece of equipment is the Blower Door!

The blower door is used to depressurize a house so that we can determine which areas of the home are allowing air leakage to occur. It basically works like this: The blower door is set within the framework of an open exterior door.  It consists of a frame and a vinyl covering.  A large fan is set into the special opening in the bottom of the blower door and a manometer is hooked up to the fan. The fan is turned on and the speed is controlled by the manometer which tells how much air is being pulled out of the house.

My favorite part is seeing the homeowners’ reactions when the fan is turned on and they can physically feel air passing by them!

Surprised woman

My next favorite part is walking around the house following the air currents and showing the homeowners all the gaps and cracks and issues we have found.

One customer asked me why his curtains were moving. I asked him if there was a vent near the window. There was, but he didn’t understand what that had to do with the curtains moving. I explained that air was being pulled out of his duct system by the fan in the blower door. Since his HVAC system had been turned off, this indicated that his duct system was not sealed! Air was being pulled from the crawlspace into the duct system and then throughout the house. If his ducts had been sealed, this wouldn't have occurred.

If you’ve never had an assessment conducted on your home, call Weatherization Plus and request not only an assessment, but a blower door test! You might be surprised just how leaky your house is. And keep in mind, the air from your attic and/or crawlspace is more than likely being sucked into your duct system where it is then distributed throughout your house. Do you really want to breathe the air from your attic or crawlspace?

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