How To Install Foam Board Insulation On Roof

To save a step i would recommend using a nailbase panel foam preadhered to osb or sometimes plywood on one side only see photo facing page.

How to install foam board insulation on roof.

Now that you know your options there are just a few more tips that you might need before you get started with installing your rigid foam insulation. Insulated roof assemblies can be vented or unvented. 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. It will degrade its r value.

The snugness of the foam itself should be sufficient to hold the strips. Position the foam board between the rafters and push it upward until it fits snugly against the underside of the roof deck. 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. All foam boards absorb water vapor.

Flat roof insulation installation the rigid foam board insulation we used was 2 thick and came in 4 x 8 sheets. More insulation on the exterior is good. It will help you to eliminate problems that may come when the house becomes extremely cold in the winter and terribly hot in the summer. Cover the insulation with a vapor barrier before you install it.

Over the foam you will need something to nail the roofing to usually a solid sheet of plywood or osb. There are at least two good reasons why this approach makes more sense than installing the insulation under the roof sheathing. Available in both foam and rigid form choose the board type. Insulation board should be added between the old and new roof systems to ensure proper insulation and to reflect heat from the outside.