Exterior Rigid Foam Insulation R Value

The 1 inch foam on the outside of the 2 8 is ok but you ll need more r value planning on more insulation in the wall cavity.

Exterior rigid foam insulation r value.

This foam board insulation is available with straight or tongue and groove edges to help limit air movement. House wrap is a good idea even with foam on the outside of the house. Polyurethane rigid foam is a. Rigid foam insulation one option is to use polyurethane rigid foam insulation.

R 7 5 scored squared edge rigid foam board insulation sheathing model 88wd view the owens corning exterior insulation. More effective insulation with r values ranging from 3 6 to 8 0 rigid foam sheathing has much better insulation per inch than other materials i e. 3 benefits of rigid foam sheathing. These r values are a sum meaning this should be the total r value once you add up the entire depth of insulation.

Owens corning foamular 150 1 1 2 in. For example a house with 2 6 walls in climate zone 6 would need rigid foam with a minimum r value of r 11 25. Closed cell foams are more dense and rigid typically about 2 lb cu. Falls in the middle of the three types of rigid foam insulation in both cost and r value used most in walls or below grade applications recyclable and at about r 5 per inch costs around 42 per sq.

Plywood has an r value of 1 25 and fiberglass batts have an r value of 3 14. Open cell foams are typically about 1 2 lb cubic foot. For a 1 in thick 4 8 panel comes unfaced or with a number of different plastic facings. For example if you have a type of insulation that has an r value of r 5 per inch of thickness you will need a depth of 6 inches of this insulation installed in your attic to reach r 30 if you live in zones 2 or 3.

This foam board insulation is the rigid pink or blue panels that can be found at home centers in many different thicknesses. C or thermal conductance of these materials is the reciprocal of the r value. Also included is the hugely helpful insulation zip code calculator that spells out the suggested amount of r value necessary for the different portions of a structure like foundation interior and exterior walls attic and more. It is denser than eps and provides more r value with a rating of 5 per inch of thickness.