Closed Cell Spray Foam Insulation R Value Per Inch

Spray foam insulation vs fiberglass r value is about equal for open cell insulation and about double for closed cell insulation per one inch layer.

Closed cell spray foam insulation r value per inch.

The r value of closed cell foam is r 6 5 7 per inch. 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. That means if you used foam it green closed cell which is r 7 per inch it s r value for a 3 5 deep wall cavity would be r 24 5. With foamed in place insulation it is relatively easy though not inexpensive to fill wall and ceiling cavities completely.

This is very important in situations where your code requires an r 21 for the wall but you only have a 2 4 stud because closed cell spray foam is the only way you would achieve the required r value to meet code. Two inches of closed cell foam will provide r12 r14 of insulation. If space is tight and you can only install a thin layer of insulation closed cell foam is by far the better choice. Closed cell spray foam provides a higher r value per inch 6 5 than less expensive insulation types like cellulose and fiberglass 3 5 to 3 7.

They sport an r value of 6 0 8 0 per inch of insulation about double their open cell foam counterparts. Most spray polyurethane foam is called two component foam. 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. Just like for open cell foam r values are additive.

Closed cell spray foams are between 2 and 4 lbs.