Foam Insulation Roof Rafters

When building my current home i was faced with a dilemma on how to insulate a bonus room that would be upstairs.

Foam insulation roof rafters.

The best attic insulation. For the same reason insulation shouldn t touch the roof s underside. Step 1 prepare the roof. The foam was applied to the attic rafters and walls.

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. Staple plastic or foam baffles to the roof sheathing near the eaves to keep the material away. 100 free of cfcs vocs penta bdes urea formaldehyde. Place a ridge cap over the ridge to hide the gaps.

Bare foam board one sided sheathing board or double sided which is also reference as structural insulated panels. Spray foam insulation that s convenient and easy to use. A vent baffle should be installed between the insulation and the roof decking to maintain the ventilation channel. If you are adding foam insulation to your roof rafters you must also properly ventilate the area.

Rigid foam board is just above the roof deck or an exterior insulation option. Build the rafters and secure the 5 8 inch cdx sheathing material. You can also add rigid foam insulation under the rafters which adds r value and eliminates thermal bridging through wood rafters. I live in the northeast.

Use closed cell foam it green for attic rafters. The airflow from the soffits to the ridge vent keeps the roof cool and prevents ice dams and the material will block that flow. 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. Often the r value of fiberglass insulation is too low and requires the rafters to be retrofitted making foam board a better choice.

R value of 7 in 1 inch 97 closed cell foam. The previous four options are all used beneath the roof. Get your kits the easy to use spray foam kit. Leave a gap on both sides of the roof near the ridge so air can escape.

It typically has 3 variations. Class i e 84 fire retardant meets building code spec. Encapsulating the rafter or top truss chord roof framing members with spray foam will improve the energy efficiency of the attic space. Consider using high density r 30 batts which are as thick as r 25 batts but fit into 2x10 framing.