Rigid Insulation On Top Of Roof Deck

Foamular xps insulation products 404 604 404rb and 604rb are used in prma applications.

Rigid insulation on top of roof deck.

Rigid foam is produced in various size panels 4 ft x 8 ft 4ft x 4ft etc. The 6 inches of rigid insulation added to the top of the existing roof deck needed to be done in a manner that was invisible. They often simplify insulation and air sealing details versus conventional insulation on the floor of the attic that may be compromised by numerous penetrations from recessed lighting fans equipment and ductwork. Polystyrene foam and foil faced polyisocyanurate foam.

Most types of rigid foam insulation have a higher r value per inch than fiberglass batts. Building air tightness would now preside at the top of the building enclosure at the roof deck and attic walls gables. The purpose of the requirement that rigid foam installed above roof sheathing meet certain minimum r values is to ensure that the roof sheathing stays warm enough during the winter to avoid moisture accumulation and possible sheathing rot. Install roofing underlayment flashing and cladding as per best practices.

Foamular xps insulation is the only insulation used in prma roof systems due to its excellent resistance to water absorption compared to any other type of rigid board insulation. Rigid foam insulation is available in two main types. After the roof deck is prepared the rigid foam boards need to be cut to size to fit snugly together on your roof. Densdeck roof boards are fm tested and approved as the only 1 2 gypsum product to meet the.

They had to look original. Installing stacks of rigid foam between rafters is slow fussy work but it might make sense for a do it yourselfer. The trim the frieze boards the fascia and the overhangs all had to look like they belonged. Rigid foam also does a better job of stopping air flow as long as it s carefully sealed at the edges.

Attach to deck board. Both install in the same manner but the foil faced product offers slightly more r value. Nailbase must be vented in high snow load areas. Install nailbase for cladding.

An excellent fire barrier densdeck roof boards feature a noncombustible core and inorganic surface that offer greater fire protection than other conventional commercial roofing products when applied over combustible roof decks and steel decks. Rigid insulation layers exterior to existing roof sheathing must provide sufficient thermal insulation r value to control condensation risk see climate specific guidance.