Foam Insulation Roof Rafters

The previous four options are all used beneath the roof.

Foam insulation roof rafters.

Polyurethane or polystyrene spray foams can provide thorough coverage to roof rafters and attic walls in much less time than is needed for other materials. Step 1 prepare the roof. Spray foam insulation that s convenient and easy to use. Use closed cell foam it green for attic rafters.

Unlike solid insulation products that require careful measurement cutting and fitting spray foam can cover even the most uneven surface instantly. Class i e 84 fire retardant meets building code spec. Build the rafters and secure the 5 8 inch cdx sheathing material. Place a ridge cap over the ridge to hide the gaps.

I live in the northeast. R value of 7 in 1 inch 97 closed cell foam. Get your kits the easy to use spray foam kit. This is because the effects of thermal bridging are limited which also results in the elimination of melt lines on the roof surface in cold climates.

Consider using high density r 30 batts which are as thick as r 25 batts but fit into 2x10 framing. The airflow from the soffits to the ridge vent keeps the roof cool and prevents ice dams and the material will block that flow. I still notice a smell permeating the upstairs of the house on hot days which is concerning over 5 years. Often the r value of fiberglass insulation is too low and requires the rafters to be retrofitted making foam board a better choice.

Leave a gap on both sides of the roof near the ridge so air can escape. The best attic insulation. Bare foam board one sided sheathing board or double sided which is also reference as structural insulated panels. 100 free of cfcs vocs penta bdes urea formaldehyde.

Encapsulating the rafter or top truss chord roof framing members with spray foam will improve the energy efficiency of the attic space. The foam was applied to the attic rafters and walls. You can also add rigid foam insulation under the rafters which adds r value and eliminates thermal bridging through wood rafters. A vent baffle should be installed between the insulation and the roof decking to maintain the ventilation channel.

Staple plastic or foam baffles to the roof sheathing near the eaves to keep the material away. Rigid foam board is just above the roof deck or an exterior insulation option. It typically has 3 variations. For the same reason insulation shouldn t touch the roof s underside.