Recommended home insulation r values.
Attic spray foam insulation r value.
Spray foam insulation is a great product.
These r values are a sum meaning this should be the total r value once you add up the entire depth of insulation.
Open cell foam insulation values r3 r4.
For example closed cell spray foam depending on brand can offer an r 6 or r 7 per inch.
However there are open cell spray foam insulation products actually offer r 3 7 per inch such as icynene classic and.
It has a lower r value per inch than closed cell foam and is vapor permeable.
Closed cell spray foam insulation.
The table below shows what levels of insulation are cost effective for different climates and.
Focusing on spray foam insulation materials there is a difference between the two main types.
Closed cell spray foam r values.
Insulation level are specified by r value.
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.
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.
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.
The higher the r value the better the thermal performance of the insulation.
R value is a measure of insulation s ability to resist heat traveling through it.
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 if you have a type of insulation that has an r value of r 5 per inch of thickness you will need a depth of 6 inches of this insulation installed in your attic to reach r 30 if you live in zones 2 or 3.
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.
The r value is r 3 5 to r 3 6 per inch so filling a 2 4 cavity yields about an r 13.
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.