How To Install Foam Board Insulation On Roof

Polyurethane spray foam metal roof insulation in order to add moisture barrier under metal roof you can spray the undersides of the roof by using a thick layer of polyurethane spray foam.

How to install foam board insulation on roof.

All foam boards absorb water vapor. 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. The snugness of the foam itself should be sufficient to hold the strips. 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.

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. There are at least two good reasons why this approach makes more sense than installing the insulation under the roof sheathing. 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.

Over the foam you will need something to nail the roofing to usually a solid sheet of plywood or osb. Position the foam board between the rafters and push it upward until it fits snugly against the underside of the roof deck. Keep foam board insulation away from direct sunlight prior to installation. When installing the foam use caulk or tape for maximum insulation between the material and the board or floor.

It will degrade its r value. Insulated roof assemblies can be vented or unvented. Flat roof insulation installation the rigid foam board insulation we used was 2 thick and came in 4 x 8 sheets. 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.