Spray Foam Insulation R Value 2x6

Open cell foam insulation values r3 r4.

Spray foam insulation r value 2x6.

Our open cell foam product has an r value of 3 5 per inch and in most applications a house constructed with 2x4 studs will have 3 5 inches of open cell foam thus resulting in a total r value of 12. The r value of the high density spray foam wall decreases from an installed r value of r 30 to approximately r 20 a decrease of r 10 because of thermal bridging. This gives you great r value a continuous thermal envelope and. After a ton of geeking out about wall assemblies including reading lots of articles and speaking with insulation experts builders and energy consultants my favorite assembly is nail base insulation zip r or atlas nail base on 2x4 or 2x6 framing with about 3 of spray foam.

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. 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. Choose foam it green spray foam insulation kits and don t settle for less than you deserve. The low density spray foam wall decreases from an installed insulation r value of 21 to a whole wall r value of approximately r 16.

2x6 frame looking at interior insulation and thinking chris s argument for flash and batt. 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. Open cell spray foams are between 5 and 1 lbs per cubic foot and have an r value of 3 0 4 0 per inch of insulation. If the house is constructed with 2x6 studs the r value when insulating with open cell foam can reach a maximum of r 20.

Closed cell spray foam r values. 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. 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. In your case you have a total r value of about r 27 8 and 41 of 27 8 would be r 11 4 but in fact you have about r 13 of closed cell spray foam which is more than r 11 4 so you are good.

For example closed cell spray foam depending on brand can offer an r 6 or r 7 per inch. For 6 inches r 15 or r 19 etc. If you want to install spray foam in a stud wall. Considering diy blown fiberglass insulation vs spray foam both require care to get the thickness right.

Spray foam kits are quicker and easier to use plus you get a seamless air barrier and high r value in just 1 inch.