Spray Foam R Value 2x6 Wall

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.

Spray foam r value 2x6 wall.

A typical 2 4 stud filled with open cell spray foam will have an r value between 10 5 and 14. Dense spray foam is installed. If you d like to start saving money and time today buy foam it green spray foam insulation now or call us at 800 516 0949. 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.

This r value is similar to that of r13 fiberglass batting. However fiberglass generally does not provide as tight a seal as a foam product would since it is unable to achieve as tight of a seal. 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. Spray foam kits are quicker and easier to use plus you get a seamless air barrier and high r value in just 1 inch.

There are no circumstances in which a 2x4 wall should be on the table in your location. Two staggered 2x4 frame walls with exterior foam sheets and interior fiberglass or cellulose will get you a better thermal break higher r value and a much quieter house than 2x6 construction. Using two dimensional heat flow analysis with thermal bridging effects and average framing factors it is clear that the thermal bridging through the framing bottom plate and top plate reduces the effectiveness of the spray foam insulation.