Rigid Insulation Roof Over Decking
The roof deck can be plywood metal concrete or wood planks.
Rigid insulation roof over decking. Foamular xps roof insulation for commercial buildings page 5 foamular xps roof insulation for commercial buildings foamular xps insulation is a rigid foam insulation which meets the needs of today s design professionals for a truly sustainable insulation product. Owens corning insulation products help improve thermal performance and control moisture in commercial institutional and. Rigid insulation under a cool roof in zone 3. The unique construction of densdeck provides excellent flute spanning that stiffens and provides increased foot traffic resistance to the roof deck.
Polyisocyanurate extruded polystyrene xps. Now comes the really really big point. 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. But spray foam insulation used at the underside of the roof deck would need to be covered by a thermal barrier and intumescent coatings are commonly used.
The first step with roof installation is to prepare the roof deck by getting rid of all dirt dust and contaminants. How to install insulation board over an existing roof membrane. 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.
The bottom layer of a single ply membrane roofing system is the roof deck or substrate. Materials appropriate for insulating sheathing with unvented cladding substrate include. The movement of air into indirect conditioning of an unvented attic is a slow gradual process that will not be noticeable by occupants and typically will not put any strain on the hvac system. This requires the use of soffit vents and a roof ridge vent to.
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. When installing rigid insulation in an attic to be finished as a living space you must provide a route by which hot air can escape. Currently there is no insulation anywhere and the third floor basically an enclosed attic gets crushed by heat in the summer. Plan to replace asphalt shingle roof with standing seam metal.
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