To the uninitiated, it might appear that once a new door or window is in
the rough opening and the exterior is flashed, the installation is done
and it’s time to install the trim or move on to something else.
Stopping the installation there, however, leaves out a very important
step: air-sealing the interior. Air leaks around doors and windows not
only significantly increase energy losses and make a house less
comfortable, but the resulting cold spots inside the wall also can
create condensing surfaces that wet insulation and damage framing and
Modern spray foam makes air-sealing around windows and
doors fast and easy. The secret is to use a low-pressure,
low-expansion, closed-cell foam designed for windows and doors, and to
apply it with a pro-style foam gun.
Don’t use expanding foams
(often marketed as crack-and-gap fillers), which can exert enough
pressure to distort frames and hinder door and window operation. Also,
before air-sealing, make sure that the door or window works perfectly,
because the foam makes later adjustments extremely difficult.
foam sticks tenaciously to just about anything it touches, so keep it
away from finished surfaces and home furnishings. Also, wipe away messes
on hard surfaces as soon as they occur.
You can clean up
uncured foam on soft materials with acetone or aerosol cleaners made by
foam manufacturers, but when the foam is sitting on the surface, it’s
generally easier and less damaging to let it dry and then to cut, pick,
or scrape it off.