Rigid Insulation Roof Over Decking

Materials appropriate for insulating sheathing with unvented cladding substrate include.

Rigid insulation roof over decking.

Start at the bottom of the roof and place the first piece of rigid foam insulation against the metal flashing starting at the center line. 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 bottom layer of a single ply membrane roofing system is the roof deck or substrate. Polyisocyanurate extruded polystyrene xps.

Get all the construction documentation you ll need in a single click. Most unvented attics incorporate spray polyurethane foam spf on the underside of the roof deck and attic walls. Nail it around the edges with roofing nails. Steel deck with fully adhered single ply membrane over a cover board with xps insulation over gypsum board thermal barrier or applied directly to the metal roof deck.

Rigid foam insulation installation prepare roof deck. 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. The insulation installed over the roof deck must be installed in multiple layers with joints offset in order to control convective looping at joints between insulation panels. Specify this solution zip 8 39 mb.

Attach to deck board. Suited for a wide range of applications foamular extruded polystyrene xps insulation is ideal for roofi ng applications including single ply protected roof membrane assemblies prma tapered vegetative roofs plaza decks architectural metal roofi ng and recover roofi ng.