I'm having a difference of opinion
with one of my favorite hvac contractors,
a plumber named Herb. The subject
of our disagreement is whether
the 20-year-old electrically heated
apartment buildings we are modernizing
are too tight. A too-tight house
can lead to a buildup of airborne toxins,
causing health problems for the
occupants and liability for the contractor.
It can also result in mildew
and condensation problems.
I believe these buildings are so tight
that they need central ventilation
systems to prevent these problems;
Herb thinks I'm out to lunch. Who's
right? The answer, I think, depends
on just how tight the house is. And to
find that out, you need a blower door.
What It Is
A blower door