Putting 1 Foil Faced Ridig Board Under Attic Roof

Foil insulation underlayment is recommended under a metal roof and in most cases the shiny side should be facing up but there s a catch.

Putting 1 foil faced ridig board under attic roof.

The r value of the insulation must meet local building code requirements for unvented attics to prevent condensation. 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. Install ap foil faced foam boards between rafters directly against the bottom of the roof sheathing.

Johns manville r panel rigid roof insulation board offers r values of up to r 23 6 providing high thermal efficiency. This is an even more dense and more expensive foam board insulation. 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. Foam insulation boards are the best material with which to work when undertaking a do it yourself project because foam.

There s two ways you can go about with foam board insulation. Then a second layer of plywood sheathing and asphalt shingles following the steps explained in this article. Multiple layers of foam board may be required. If you want to use them without creating a vapor barrier look for permeable iso panels faced with fiberglass.

It provides an r value of 6 per inch of thickness and often comes foil faced to help reflect radiant heat. Foam board insulation in the attic can cut down on energy costs and simultaneously promote a more environmentally sound way of daily living. However foil faced iso panels are warranted as impermeable. 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.

4 of polyiso under 4 of eps all above the original roof sheathing. Installing foam insulation boards in the attic is no that hard and can save you money compared with professional installation. Cut ap foil faced foam sheathing to fit snuggly between the rafters. Installing rigid foam insulation.

Foil insulation is a radiant barrier and it works by. 2 measure and cut the foam boards as.