Installing Rigid Foam Insulation On Roof

Cover the insulation with a vapor barrier before you install it.

Installing rigid foam insulation on roof.

Put on your roofing safety harness and secure the safety rope to the top of the roof. After installing several layers of rigid foam above the roof sheathing these workers installed plywood above the rigid foam. Unroll roofing felt to cover the plywood on the roof and nail it in place. One of the best benefits of rigid foam insulation is that it offers excellent thermal resistance at around double that of traditional insulation.

Apply continuous air control membrane to existing roof sheathing or implement continuous air control at roof sheathing. When installing the foam use caulk or tape for maximum insulation between the material and the board or floor. Remove existing roofing and non adhered underlayment to expose roof sheathing. The furring strips should run vertically from floor to ceiling or from eaves to rafters if you are installing them on a sloped ceiling.

This type of insulated roof assembly limits thermal bridging through rafters. The plywood was fastened through the rigid foam to the rafters with long screws. A helpful hint for installation is to use a straight edge along the cut line to ensure the panels fit best. Use a straight edge knife or utility knife to cut the panels to size.

Install 1 by 3 furring strips over the insulation panels on top of each stud. It will degrade its r value. All foam boards absorb water vapor. Keep foam board insulation away from direct sunlight prior to installation.

Install rigid insulation board in multiple layers with joints offset vertically and horizontally between adjacent layers. Nail metal flashing along the edges of the. To install measure the foam insulation panels to the roof s dimensions.