Insulating Flat Roof With Spray Foam

Spray foam insulation is in a liquid form until it comes into contact with a surface where it begins to expand from its initial size up to a hundred times.

Insulating flat roof with spray foam. Spray polyurethane roofing is still a thing its arguably the best insulation there is and you d install it right over the existing roll roofing. For a 1 inch board equivalent of 6 r value. This means the insulation can be sprayed onto the underside of the flat roof to create a solid water resistant and pest resistant protection barrier. Composite insulation works in flat and low sloped.

While expensive the best insulation is polyiso rigid foam. If the guy is worried about spray foam in the house then put it on the roof. Foam it green 602 closed cell spray foam insulation kit. You must meet the same minimum code requirements for the spray foam layer and the total assembly as for the rigid foam plus air permeable insulation approach.

We recommend having at least 20 r value worth of material for optimal energy efficiency. It is top quality and the most cost effective product for your flat roof. 00 0 40 oz free shipping. Install composite insulation made from expanded polystyrene or eps foam laminated with a fiberglass facer that meets ul class a requirements.

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. 3 8 out of 5 stars 129. Closed cell polyurethane spray foam will prove ideal for thermal insulation of a flat roof. Moisture generated indoors or that infiltrates into the home is responsible for the bulk of the moisture in an attic insulated with spray foam on the underside of the roof sheathing.

Touch n seal high density spray foam roof insulation kit 3 0 pcf closed cell foam 120 bf. What s left he adds are using spray foam insulation on the underside of the roof sheathing or rigid foam on top of the roof sheathing. 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. Add some wood blocking at the roof edge for fascia to match insulation thickness and coat the spray foam and done.

Holladay informed west that these options were discussed in a recent gba article insulating low slope residential roofs. Lstiburek takes blame for bad language. The effective roof insulation layer may range in thickness from 3 to 12 cm as needed. A layer of spray polyurethane foam can be installed against the underside of the roof sheathing with the rest of the rafter cavity filled with air permeable insulation.

It s not coming from above the roof and it s not some new moisture source resulting from the spray foam.