30 | BUILDING SCIENCE Rx — December 2018
the right side...over there where the filter is attached. So that
filter does nothing because air doesn't move through it.
Filtration can be an important part of good indoor air
quality. Unfortunately, there are some significant obstacles
to overcome if you want it clean up your air. Professor Jef-
frey Siegel has been studying the effectiveness of filtration
in real homes and has found that the average home in their
study has a filtration effectiveness of about 20%.
How's your filter doing?
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Chart of filter particle trapping used with permission by John
Semmelhack. Photo filter installed outside the airstream
used with permission by Jamie Clark.
Allison Bailes, III, Ph.D., Energy Vanguard, LLC, Decatur, GA
Dr. Bailes has a PhD in physics from the University of Flor-
ida. After starting off on the traditional academic path of
teaching, he found a way to use his interest in energy and
the environment, as well as his love for buildings, especial-
ly homes. After finishing the construction of his own green
home in 2003, he became a home energy rater, and later
founded Energy Vanguard in 2008.
Energy Vanguard is more about teaching and less about
fixing, although they do offer HVAC design services. It's fo-
cused more on the big picture—creating markets, spread-
ing the word (such as for Energy Efficient Mortgages), ex-
panding networks—and less on individual components. The
company is on the forefront of change—the vanguard—in
the way we see and use energy in our homes. For more
information, visit https://energyvanguard.com.
