Spray In Foam Insulation R Value

According to industry publication fine home building the r value for open cell spray foam is between r 3 5 r 3 6 per inch.

Spray in foam insulation r value.

Insulation materials run the gamut from bulky fiber materials such as fiberglass rock and slag wool cellulose and natural fibers to rigid foam boards to sleek foils. Rigid foam boards trap air or another gas to resist conductive heat flow. Closed cell spray foam insulation. If you want to install spray foam in a stud wall and price is no object then it would seem to make sense to specify closed cell spray foam right.

The r value of spray foam insulation is approximately 6 per inch so those using spray foam as their insulator will need about 6 3 inches of thickness to reach r 38. By expanding 100 times its original size icynene seals cracks and gaps in attics walls ceilings and other spaces where air might escape. R values are additive so you can multiple the number of inches of insulation thickness times the r value to arrive at a total insulation value. Focusing on spray foam insulation materials there is a difference between the two main types.

Open cell spray foam insulation is air impermeable and is applied with a minimum of 3 5 on average and can be used for attics interior floors walls and soundproofing. Bulky materials resist conductive and to a lesser degree convective heat flow in a building cavity. All these have r values ranging from r 3 2 to r 3 8 per inch. Icynene sprayed in foam is an insulation and air seal system that works to help ensure that your home doesn t suffer from air loss while providing an effective r value.

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. However there are open cell spray foam insulation products actually offer r 3 7 per inch such as icynene classic and. 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 has a far better r value per inch than other less effective insulations like cellulose fiberglass or even open cell foam.

Traditional insulation such as cellulose or fiberglass is not comparable to spray foam insulation in r value as those insulation methods use r value of heat transfer. 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. Closed cell spray foam r values. For 6 inches r 15 or r 19 etc.

For example closed cell spray foam depending on brand can offer an r 6 or r 7 per inch.