Page 33 - CodeWatcher Winter 2017 Issue

“When I do forensic
investigation on
envelopes that
have failures, it is
routinely revealed
that a blower door
test either wasn’t
done or was
performed at the
end of construction
and without regard
to sourcing and
correcting air leaks.”

Better Testing,
Better Homes

I think RESNET, which sets the bench-

mark for high-performance building,

has an opportunity to lead the industry

by making sure raters, builders, and

A pre-drywall blower door test is essential for an airtight, durable house. homeowners are educated on the val-
ue-added service of a pre-drywall test.

¦¦ Is the crew’s training sufficient to achieve the high level This would be a win-win for the organization because it

of performance and durability we seek? would make its raters more successful because the houses

¦¦ Is it time for a refresher course for our plumber and/ they rate would be better performing and more durable, and

or electrician? it would give them more work.

¦¦ Which part of tight doesn’t the HVAC contractor Builders may grumble over this, of course, but if I were

understand? a rater, I’d point out the obvious upside of the practice:

I admit that most of my crew’s fervor for driving every “Conducting two blower door tests is going to save you from

structure well below 1 ACH @ 50 is based on energy building failures and problems down the road.”

performance (and bragging rights), but the long-term I’ve been through HERS training, and have hosted a

durability issue is my greater concern. A leak in the ridge number of raters here at SIPschool over the years. My

that yields a loss of efficiency by fractions of a percent may be number-one recommendation to them is to use the blower

large enough to open the door for failure years in the future. door test to promote quality of workmanship and durability

When I do forensic investigation on envelopes that have of structure. The “standard” end-of-construction test does

failures, it is routinely revealed that a blower door test either nothing for ensuring either of these.

wasn’t done or was performed at the end of construction and A builder that is truly in the zone of efficiency and durability

without regard to sourcing and correcting air leaks. would never overlook the opportunity for improvement by

It’s doubly frustrating when I speak to a HERS Rater about properly employing this simple test. CW

mid-construction blower door tests only to hear “That’s not

required” or “We never do that.” Al Cobb is the Director of SIPschool.

www.codewatcher.us January 2017 / CodeWatcher 33