Building a Denver Custom Home: The Blower Door Test

Building a Denver Custom Home: The Blower Door Test

“Does TRC Residential build a lot of custom homes around Denver?” asked the inspector.  “Because I do
a lot of these tests and this house is off-the-charts tight.”

As he continued his praise, the inspector was beginning to pack up the equipment he had just used to
perform a “Blower Door” test, one that TRC Residential passed with flying colors.  I explained that over
40 years of building experience went into the construction of this nearly complete custom home.
“Well, I’m tellin’ ya, man.  This house is TIGHT.” he said.

The tightness to which he was referring was how well sealed the home was from outside
elements.  Everything you can imagine, from the foundation to the chimney, the windows and doors,
and everything in between needed to be as airtight as possible for the home to be environmentally
efficient.  The results of this test, the first one for which I was present, needed to be at or above a
number specified by building code and they also serve as a pretty good indication of overall quality of
the home.

The test was very interesting to observe.  Our inspector rolled out a section of red vinyl type material
that had a round hole and a window.  He affixed it to an adjustable frame and methodically fit this to the
inside of the front door frame, essentially replacing the open front door.  To the open hole he fastened a
large fan and carefully arranged what looked to be digital diagnostic equipment.



After making sure that all other doors and windows were completely shut, the inspector turned on the
fan, blowing air from the inside of the home out to the front yard.  In fact, it would be more correct to
say he was sucking air from inside the house with his contraption and I could feel it – a sensation in my
ears not unsimilar to the popping I experience when climbing to cruising altitude in an airliner.  In just a
few seconds, he had literally dropped the air pressure inside the home.




Of course this is the desired result.  If the air pressure didn’t drop enough (or at all), the test would have
shown that the house wasn’t sufficiently sealed.  An insufficiently sealed house allows the winter cold in
and comforting warm air out, the same dynamic reversed for hot summer months.  This lack of
efficiency can be expensive for a homeowner over time and is not environment-friendly.  What seemed
to have our inspector so impressed was not that this house was sufficiently sealed, but just how well
sealed the house really was.  When he said “tight”, he meant airtight.

He explained that the number was above the standard set by building code… by a ton.
The thing that was even more interesting and fun for me was that our inspector was the only one in the
house that day that was surprised at this incredible result of the Blower Door Test.  This number
represented the attention to detail in every step of a TRC Residential custom home.  From foundation to
finishing, it’s not just about getting the job done, it’s about getting the job done right and handing the
keys to the homeowner knowing that they are taking ownership of the highest quality building available.
Moments like this are routine here at TRC.  Confidence going into inspections turns into a quick pat on
the back before the team gets back to work.  High-quality Denver area custom homes don't build themselves.

When you’re ready to get started on your custom home, remodel or room addition, get in touch with
TRC Residential so we can work together to make it yet another example of the very best. Because that’s
what we are.

Just ask the inspector.


by Colin Spencer