How do I Insulate Unvented Attics?

Wear the appropriate safety gear when working with insulation. The best outfit is a bodysuit with a helmet and respirator to protect you from stray insulation particles and insulation inhalation. If you cannot get one of these suits, then you can wear safety goggles, thick gloves and a respirator mask.

Place the insulation blower as close to the entrance for the attic as possible, This will allow you to spray the insulation throughout the attic without having to move the machine to reach the far corners. Try to rent or purchase the longest blowing tube possible as this will make it easier to reach all parts of the attic.

Empty the attic of all boxes, furniture, building supplies and any other items placed in it for storage. The attic should be completely free of all contents. This will allow the insulation to fully cover the roof of the attic, while enabling you to freely access all parts of the attic floor.

Place a sturdy board between beams in the attic floor, if the attic is not finished. This will prevent you from falling through the attic floor and the ceiling below. This will also prevent expensive repairs from damaging the attic floor. Stand on the board while spraying the insulation. Move the board to a new location to apply the insulation there.

Place the polyurethane spray foam inside the insulation blower. Place as much insulation inside the blower as possible. You may have to refill the blower several times with new insulation before the process is complete.

Spray the insulation on the attic roof between the rafters. Spray the insulation to a depth of about 2 to 2 1/2 inches thick. This is thick enough to provide a R-13 insulation rating. Installing this amount of insulation will prevent water from seeping through the insulation into the attic, which is sometimes a problem for unvented attics.