Installing Rigid Foam Insulation In An Attic

All foam boards absorb water vapor.

Installing rigid foam insulation in an attic.

Start at one corner of the attic and lay the piece of insulation lengthwise like a piece of drywall. It will degrade its r value. Fasteners should be long enough to penetrate in to the rafter a minimum of inch. Use a chalk line or t square to mark where it needs to be cut.

When installing foam insulation boards in the attic make sure you start from one corner and work your way around the room. In addition to installing the foam board on the underside of the roof deck you can attach it to the bottom edges of the. For more information on the work i have described see two ways to insulate attic kneewalls. Once the attic is prepared then start to install the insulation.

A table saw will also cut the board but it. Alternate fasteners may be used with the type and length as recommended by their manufacturer for securing foam plastic insulating sheathing. Foam insulation boards can be attached to concrete walls as well and in such a case care should be taken not to chip the cement. Fasten foam insulation boards to the interior of the rafters using screws or nails with 1 inch minimum washers or caps.

Cover the insulation with a vapor barrier before you install it. The superattic system creates a continuous air and insulation barrier directly beneath the attic roof with no thermal bridging to compromise energy. The superattic system utilizes proprietary silverglo rigid foam insulation panels to fully seal and insulate the attic directly beneath the roof rafters and directly inside the gable ends. When installing a foil faced foam board insulation.

Cut the insulation with a utility knife. Seal the perimeter of each piece of rigid foam with caulk canned spray foam or high quality tape. How do you install rigid foam board. Mark the insulation where it lines up with the center of the rafter closest to the farthest edge.

If there is any horizontal section of these joist bays that are exposed on one side to unconditioned space then the joist bays need to be insulated. Keep foam board insulation away from direct sunlight prior to installation. You can use a utility knife to cut using the same cut and snap process you use with drywall.