Tom Balderston, Conservation Services Group

A blower door test exposes energy waste. At the March monthly walkthrough, a blower door test at zHome demonstrated the importance of efficient energy use and how zHome maintains zero net energy emissions.  A blower door is a fan that mounts in the frame of an exterior door.  As the fan pulls air out of the house, it lowers the air pressure inside.  The outside air flows in through unsealed openings, exposing air leaks in the building.  Just walking around your house, you will be able to feel the air right where it’s leaking out of your house: your vents, windows, roof or wherever.  Part of the test requires taking measurement of air flow.  In essence, a blower door test just exaggerates the natural air leakage rate, allowing someone to efficiently air seal the building. Luckily, this energy inefficiency is something that can easily be fixed through good insulation and extremely tight exterior walls. Blower door tests can also calculate air changes per house to see how many times the air within the house is replaced over the course of a day.

The building is air sealed while the blower door is running, measuring results as it is sealed. Blower door directed air sealing is a process that makes it possible to determine the effect of each particular measure or how much reduction has occurred over a certain amount of time.  Directed air sealing is more productive because it allows for sealing to be done where the best results will be obtained.

Building code does require energy efficiency, but energy code lags behind best practices. zHome is shooting for an air leakage rate that is half of the code requirements.

Watch this video to see Tom Balderston of Conservation Services Group walk us through a real blower door test!

zHome blower door test from zHome on Vimeo.