Over Deck Roof Insulation

Can be used as a cover board in re roofing and new construction proven to reduce the tendency for blistering in hot asphalt applications.

Over deck roof insulation.

Concrete contains a significant amount of moisture and there is no test to accurately tell if the concrete is dry enough to install the roof on top of it. Roofs over concrete decks should always have a vapor barrier installed. Typically this would be achieved by adding polyiso insulation above the plywood deck. Insulated roof assemblies can be vented or unvented.

However most cathedral ceilings and low slope flat roofs are insulated roof assemblies. Foamular tapered roof insulation provides a thermally effi cient moisture resistant positive drainage slope for use under single ply or other types of roofi ng systems. Drill holes in the sheathing and blow insulation into the empty wall cavity before installing the new siding and. Wall insulation whenever exterior siding is removed on an.

The fully adhered membrane wrapped down over the cut back roof deck to tie into the wall water control layer and air control layer photograph 11. Enjoy interior design freedom with above deck roof assemblies that allow for open interior ceilings and spaces. Materials appropriate for insulating sheathing with unvented cladding substrate include. The solid substrate for fluted metal decks is typically a gypsum underlayment and the concrete is the solid substrate for concrete decks.

Add insulation above the roof deck this approach fits current building science thinking in terms of putting the thermal control layer on the outside of the building structure. Add r5 to r6 insulative wall sheathing beneath the new siding. Recover roof insulation insulation low slope single ply above deck roof insulation system with cover board prma vegetative roof insulation vegetated waterproofi ng system. The right thickness would need to be calculated to move the dew point above the plywood deck where air infiltration is minimized.

On the front of the roof edges the original roof deck sheathing was cut back flush with the wall and the fully adhered membrane folded down around the rafter tails to catch the. Polyisocyanurate extruded polystyrene xps. Like fully adhered insulation fully adhered vapor barriers need a solid substrate below. Add r5 insulative wall sheathing beneath the new siding.

With this kind of roof the insulation follows the slope of the roof. A roof over a vented unconditioned attic does not need to include any insulation. 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. 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.

Robustness exceptional dimensional stability and rated for extreme hail rockwool stone wool insulation roof boards have meet both the fm severe hail and the ul 2218a standard for impact resistance.