Putting 1 Foil Faced Ridig Board Under Attic Roof

Then a second layer of plywood sheathing and asphalt shingles following the steps explained in this article.

Putting 1 foil faced ridig board under attic roof.

Cut ap foil faced foam sheathing to fit snuggly between the rafters. I have at my disposal four inch polyiso board with the foil facing. However foil faced iso panels are warranted as impermeable. Foam insulation boards are the best material with which to work when undertaking a do it yourself project because foam.

4 of polyiso under 4 of eps all above the original roof sheathing. There s two ways you can go about with foam board insulation. R panel is manufactured with a closed cell polyisocyanurate foam core bonded to fiberglass reinforced facers and designed for use over metal nailable and non nailable roof decks with a variety of membrane systems. 2 measure and cut the foam boards as.

We live in zone 5 suburb of chicago and are hopefully about to put rigid foam above the roof sheathing on just the northeast roof portion of our roof. If you want to use them without creating a vapor barrier look for permeable iso panels faced with fiberglass. Installing rigid foam insulation. My plan was to rip one inch strips of wood to put on the back of the roof decking then cut the polyiso board to fit in between the rafters leaving one inch gap for ventilation as well as a 1 4 inch gap on either side to seal after installation.

Johns manville r panel rigid roof insulation board offers r values of up to r 23 6 providing high thermal efficiency. Foam board insulation in the attic can cut down on energy costs and simultaneously promote a more environmentally sound way of daily living. It provides an r value of 6 per inch of thickness and often comes foil faced to help reflect radiant heat. The r value of the insulation must meet local building code requirements for unvented attics to prevent condensation.

Installing foam insulation boards in the attic is no that hard and can save you money compared with professional installation. Foil insulation is a radiant barrier and it works by. Install ap foil faced foam boards between rafters directly against the bottom of the roof sheathing. Select rigid foam insulation boards that are at least 1 2 inch less in thickness than the rafter space is deep if you plan to finish the attic as living space.

I have 2x10 rafters. Polyiso comes in several thicknesses and is used over house sheathing underneath siding or in attic spaces where its reflective properties are very effective.