Rigid Foam Insulation Under Roof Deck

Polyurethane spray foam metal roof insulation in order to add moisture barrier under metal roof you can spray the undersides of the roof by using a thick layer of polyurethane spray foam.

Rigid foam insulation under roof deck.

Additionally densdeck has been shown to withstand de lamination deterioration warping and jobsite damage more effectively than other roofing membrane substrates such as paper faced gypsum board fiber board and perlite insulation. This type of insulated roof assembly limits thermal bridging through rafters. This construction approach was first used in the 1970s and it has been implemented much more widely since it was first included in the international code council s icc model building code in 2007 irc section 806 4. The plywood was fastened through the rigid foam to the rafters with long screws.

It will help you to eliminate problems that may come when the house becomes extremely cold in the winter and terribly hot in the summer. The snugness of the foam itself should be sufficient to hold the strips. After installing several layers of rigid foam above the roof sheathing these workers installed plywood above the rigid foam. A good rigid insulation is insulating concrete which can be mixed and placed on the job.

Install nailbase for cladding. I agree with the comment that it sure is a lot of work for so little insulation our standard approach would be about 8 inches of xps screwed thru 2x4 s laided flat with timber loks. Rigid foam under roof sheathing indydog. The unique construction of densdeck provides excellent flute spanning that stiffens and provides increased foot traffic resistance to the roof deck.

This can be perlite concrete vermiculite concrete concrete made with polystyrene aggregate or cellular concrete. Position the foam board between the rafters and push it upward until it fits snugly against the underside of the roof deck. Strip the old roof lay down ice and water membrane add the foam overlapped screw down the 2x4 s add sheathing shingle. Rigid insulation layers exterior to existing roof sheathing must provide sufficient thermal insulation r value to control condensation risk see climate specific guidance.

Most unvented attics incorporate spray polyurethane foam spf on the underside of the roof deck and attic walls.