Rigid Foam Insulation Roof Detail

Insulated roof assemblies can be vented or unvented.

Rigid foam insulation roof detail.

While all foam insulation products are derived from petroleum some of the key differences include water resistance r value per inch compressive strength facings permeability to water vapor and evidently cost. In warm climates zones 1 through 4 low density open cell spray foam insulation is the typical choice since it is vapor permeable and will allow drying of the exterior sheathing and roof framing if they happen to get wet via diffusion into the interior of the building. There are lots of different ways to insulate this type of roof but one of the best methods calls for the installation of rigid foam insulation above the roof sheathing. There s a reason polyiso rigid foam insulation is used in more than 70 of commercial roof construction as well as in many residential builds.

If providing a vented over roof. There are at least two good reasons why this approach makes more sense than installing the insulation under the roof sheathing. Expanded polystyrene eps extruded polystyrene xps and polyisocyanurate are the most used types of rigid foam insulation. Foamular roof insulation can help contribute to credits under the leadership in energy and environmental design leed program of.

Install rigid insulation board over the air control layer in multiple layers with joints offset vertically and horizontally between adjacent layers. Foamular roof insulation is made with a high percentage of pre consumer recycled material. It is the only xps insulation with certifi ed recycled content certifi ed by scientifi c certifi cation systems. Detail the outer layer of the insulating sheathing as a drainage plane.

Adding the metal roof insulation can be done easily when you renovate your house. Flat roof insulation installation the rigid foam board insulation we used was 2 thick and came in 4 x 8 sheets. Once the roof demo was complete and the flat roof was cleared of any remaining debris some rotted 2x material around the perimeter of the roof was replaced. Or you may also consider metal roofing over rigid insulation details even though it might be a bit pricier.

Second the foam will keep the sheathing warm so moisture passing through the wall or roof will find no cold surfaces for condensation to occur. All atlas acfoam polyiso insulation boards are qualitymark certified providing consumers an easy way to identify premium products that meet or exceed building codes for the best in roof performance. You will need to hire some well trained roofing insulation experts to make a more energy efficient home. Transfer the markings for framing locations through each layer of insulating sheathing.