Rigid Insulation Roof Over Decking

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.

Rigid insulation roof over decking.

Materials appropriate for insulating sheathing with unvented cladding substrate include. Specify this solution zip 8 39 mb. Rigid foam insulation installation prepare roof deck. It is an acceptable practice to install a new roof over an existing roof membrane system provided that the roof deck is structurally sound and has been properly prepared to support the added load.

Get all the construction documentation you ll need in a single click. 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. Attach to deck board. The rigid insulation over roof would have controlled the temperature of the condensing surface the underside of the roof deck so that i would not have had to use the spray foam except at the perimeter to provide the air seal to the tops of the walls.

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. After the roof deck is prepared the rigid foam boards need to be cut to size to fit snugly together on. Nail it around the edges with roofing nails. The bottom layer of a single ply membrane roofing system is the roof deck or substrate.

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