Attic Spray Foam Insulation R Value

Recommended home insulation r values.

Attic spray foam insulation r value. 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. I ve been in plenty of these homes and can tell you that when spray foam is installed properly they outperform 99 of fiberglass batt insulated stick built homes. 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.

However there are open cell spray foam insulation products actually offer r 3 7 per inch such as icynene classic and. The higher the r value the better the thermal performance of the insulation. Insulation level are specified by r value. Homes insulated with it can be some of the most efficient and comfortable homes built.

Closed cell spray foam r values. It has a lower r value per inch than closed cell foam and is vapor permeable. The r value is r 3 5 to r 3 6 per inch so filling a 2 4 cavity yields about an r 13. The table below shows what levels of insulation are cost effective for different climates and.

I can also tell you that 73 of all statistics are made up on the spot so please don t ask for. Focusing on spray foam insulation materials there is a difference between the two main types. R value is a measure of insulation s ability to resist heat traveling through it. These r values are a sum meaning this should be the total r value once you add up the entire depth of insulation.

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. For example closed cell spray foam depending on brand can offer an r 6 or r 7 per inch. Spray foam insulation is a great product. 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.

For 6 inches r 15 or r 19 etc.