Spray Foam Insulation R Value 2x4

Insulation is rated in two ways r value and u value.

Spray foam insulation r value 2x4.

Ultimate spray foam insulation has a few different foam products of different densities. The installed insulation r value depends somewhat on the system manufacturer but generally speaking high density foam 2 0 pcf ranges between r 5 5 and r 6 5 per inch for the aged r value and low density foam 0 5pcf has an r value of approximately r 3 6 inch. And with an r 7 per inch you get to r 21 in 3 inches of foam. In a 2x4 wall you can use spray foam but it has to be closed cell not open cell.

The r value is a calculation which measures the flow of heat through an insulation product or its. To meet r 20 requirement if that is what code says in your location. Foam it green sprays on fast creating a seamless air and moisture barrier. It performs much better than any form of batt for stopping air flow but it is not as complete of an air seal as closed cell spray foam.

But that carries it s own added cost. 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. Find your zone on the map and then use the above insulation r value chart to determine the level of insulation you need to properly insulate your attic walls floors and crawlspaces. Just like for open cell foam r values are additive.

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. Closed cell spray foam aka two pound foam is denser than open cell at about 2 pounds per 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 s obvious advantages compensate for its slightly higher price tag of 15 to 30 for the same thickness.

Insulating a 2 4 wall with foam it green is the quickest and easiest way to meet code standards. How to achieve r 21 in a 2x4 wall. These r values are a sum meaning this should be the total r value once you add up the entire depth of insulation. Closed cell foam is r 7 25 per inch.

Its r value is roughly 6 5 per inch. Closed cell spray foams are between 2 and 4 lbs. They sport an r value of 6 0 8 0 per inch of insulation about double their open cell foam counterparts.