Closed Cell Foam R Value Chart

For 6 inches r 15 or r 19 etc.

Closed cell foam r value chart.

Closed cell spray foam has a far better r value per inch than other less effective insulations like cellulose fiberglass or even open cell foam. Polyurethane and polyisocyanurate are both closed cell foams. Why spray foam insulation is so effective in meeting code requirements is that it has a higher r value per inch of product used than batts. Use the following chart to estimate an ideal r value for your insulation project.

They contain low conductivity gases in the cells usually one of the hcfc or cfc gases the higher r values r 7 0 to 8 0 are the result of thermal resistance of the gases in the cells. That said the table is useful. It demonstrates the calculation method and does a good job of estimating the incremental r value attributable to an upgrade from open cell to closed cell foam. Along with knowing the r value of a particular insulation it is also important to calculate the r value of a total system.

As always should you have any questions or require any assistance in planning your spray foam insulation job please contact us we are always happy to help. For example closed cell spray foam depending on brand can offer an r 6 or r 7 per inch. Closed cell spray foams are between 2 and 4 lbs. In comparison an inch of blown fiberglass insulation has an r value of 3 1 3 4 and an inch of blown cellulose in an attic has an r value of 3 2 3 7.

The r value is r 3 5 to r 3 6 per inch so filling a 2 4 cavity yields about an r 13. Closed cell spray foam r values. Closed cell polystyrene spray foam 1 inch thick 6 5. Our r value guide to rigid insulation includes the doe s recommended insulation by zone chart r value calculator and base building material r values chart.

Additional r value for a masonry wall constructed using these materials needs to add the insulating value of additional wall components typically included such as 1 solid foam polyisocyanurate r 8 extruded polystyrene r 5 expanded polystyrene r 4 or 1 of perlite r 2 7 and for an exterior air film winter no wind r 0 17 an interior. Open cell polyurethane spray foam 3 5 inches thick 12 6. Two inches of closed cell foam will provide r12 r14 of insulation. It has a lower r value per inch than closed cell foam and is vapor permeable.

As a benchmark one inch of solid wood has an r value of 1. Closed cell spray foam insulation. Just like for open cell foam r values are additive. Expanded polystyrene foam board.