Rigid Foam Insulation Attic Roof

Typical thicknesses range from inch to 2 inches with estimated r values of r 3 for the inch to r 10 for the 2 inch board.

Rigid foam insulation attic roof.

Eps is by far the most versatile of the three rigid insulation options. Most unvented attics incorporate spray polyurethane foam spf on the underside of the roof deck and attic walls. Measure the length and width between two rafters in your attic and transfer the measurements to a 4 ft by 8 ft of rigid foam insulation board. This construction approach was first used in the 1970s and it has been implemented much more widely since it was first included in the international code council s icc model building code in 2007 irc section 806 4.

It is lightweight and easy to work with. The superattic system utilizes proprietary silverglo rigid foam insulation panels to fully seal and insulate the attic directly beneath the roof rafters and directly inside the gable ends. It can be applied on the roof floor and walls and it s most widely used in structural insulated panels and insulated concrete forms. Now someone will look at an insulation value chart and says but foam has a higher r value per inch so it s better insulation since you have non infinite space to put it in.

A 4 by 8 board weighs next to nothing and can easily be cut to fit. 2 snap a chalk line between the length measurements. Rigid foam panels are about 0 10 0 15 square foot r as we can see in terms of insulation value for your money the batts take a bat to all challengers.