Exterior Roof Insulation Details

Minimum nail length must accommodate sheathing and penetrate framing a minimum 1 inches.

Exterior roof insulation details. Gable end detail overhang cut and then rebuilt to hide the thickness of the over roofing rigid insulation. Roof edge detail overhang extended to hide the thickness of the over roofing rigid insulation. Building codes are clear. Install nailbase for cladding.

Current building code does provide prescriptive means to attach cladding over exterior insulation table r704 3 note v. Single ply roof insulation. Termites can tunnel from the soil up behind the foam panels and attack the structure of a house without being noticed. Current pneumatic nailers have maximum fastener lengths of 3 to 3 5 which limits insulation thicknesses to 1 5 max.

Single ply roof systems can provide an easy to install seamless roof assembly. Thermalwall ph rigid eps insulation board for insulating the exterior walls of homes the advantages are plenty here panels are between 4 5 inches and 8 inches thick the exterior insulation is continuous and they can be attached with 6 inch 10 screws from 4 to 6 inches long. Detail drawings illustrations lapolla distributes an architectural binder available in print and electronic format. The easiest way to insulate your roof is with one or two layers of rigid foam insulation installed above the roofing.

The binder includes product specifications detailed drawings and illustrations technical datasheets and a number of informational brochures. If you are planning to install metal roofing then you would install asphalt felt above the rigid foam followed by 1x4 or 2x4 purlins 24 inches on center then the metal roofing. Install two layers of insulation to the roof staggering the seams offsetting the joints and taping outer layer. New roof sheathing on top can extend out to create a new roof overhang.

There are at least two good reasons why this approach makes more sense than installing the insulation under the roof sheathing. 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. Nailbase must be vented in high snow load areas. Install roofing underlayment flashing and cladding as per best practices.

Extend the foam 4 inches past the walls so that you can add foam to the walls later and tie it in to the roof. When insulating foam is used to wrap the exterior of a home it provides an undetected pathway connecting soil to structure. Insulated roof assemblies can be vented or unvented. The 6 inches of rigid insulation added to the top of the existing roof deck needed to be done in a manner that was invisible.