Insulating A Roof With Rigid Foam

Insulated roof assemblies can be vented or unvented.

Insulating a roof with rigid foam.

Rigid foam boards come in different material compositions varying thicknesses and different insulating r value properties. Eps is by far the most versatile of the three rigid insulation options. It can be applied on the roof floor and walls and it s most widely used in structural insulated panels and insulated concrete forms. A continuous layer of rigid foam insulation in wall and roof assemblies leads to lower energy consumption an environmental plus to be sure.

Install nailbase for cladding. Nail it around the edges with roofing nails. 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.

Start at the bottom of the roof and place the first piece of rigid foam insulation against the metal flashing starting at the center line. Eps is also the most inexpensive of the three types of rigid foam insulation while also meeting the required building and energy codes. Rigid insulation layers exterior to existing roof sheathing must provide sufficient thermal insulation r value to control condensation risk see climate specific guidance.