Open Cell Foam R Value Chart

As a benchmark one inch of solid wood has an r value of 1.

Open cell foam r value chart.

Rmax r matte plus 3 1 2 in. Closed cell spray foam insulation 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. R 3 2 polyisocyanurate rigid foam insulation board r matte plus 3 thermasheath 3 is rigid foam r matte plus 3 thermasheath 3 is rigid foam plastic thermal insulation board. 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.

They sport an r value of 6 0 8 0 per inch of insulation about double their open cell foam counterparts. Closed cell open cell spray foam r values. R value is an important insulation term about measurement. C or thermal conductance of these materials is the reciprocal of the r value.

Closed cell foams are more dense and rigid typically about 2 lb cu. 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. Two inches of closed cell foam will provide r12 r14 of insulation. Open cell foams are typically about 1 2 lb cubic foot.

Open cell spray foam has an r value of about r 3 7 per inch while closed cell spray foam has an r value that may be as high as r 6 5 per inch. Closed cell spray foams are between 2 and 4 lbs. Expanded polystyrene foam eps is the cheapest and least used foam board product on the market. Foam insulation densities vary among closed cell vs open cell forms.

Just like for open cell foam r values are additive. R value is the only measurement used in building codes today however it is not the only way to stop energy loss. Closed cell polystyrene spray foam 1 inch thick 6 5. Open cell polyurethane spray foam 3 5 inches thick 12 6.

When applied on the interior open cell spray insulation provides performance advantages that differ from those of closed cell spray foam used on the exterior. Along with knowing the r value of a particular insulation it is also important to calculate the r value of a total system. This product typically has an r value of 3 6 to 4 0 per inch of thickness. It measures the effectiveness at stopping energy loss by way of conduction one of the 3 forms of energy transfer.

Both closed cell spray foam and open cell spray foam insulation can be used effectively in commercial building designs to allow the building to achieve energy efficiency and consistent performance. I also recommend you read a recent article about open cell vs closed cell foam products to understand the differences between the two product types. The r value is r 3 5 to r 3 6 per inch so filling a 2 4 cavity yields about an r 13.