R Value Spray Foam Thickness Chart

Recommended home insulation r values.

R value spray foam thickness chart.

For example closed cell spray foam depending on brand can offer an r 6 or r 7 per inch. It has a lower r value per inch than closed cell foam and is vapor permeable. Use the following chart to estimate an ideal r value for your insulation project. Insulation level are specified by r value.

For 6 inches r 15 or r 19 etc. A typical 2 4 stud filled with open cell spray foam will have an r value between 10 5 and 14. 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. Polyiso insulation thickness r value chart.

The r value is r 3 5 to r 3 6 per inch so filling a 2 4 cavity yields about an r 13. Closed cell polystyrene spray foam 1 inch thick 6 5. R 0 77 30 phenolic foam insulation r values. 4 8 7 21.

4 5 21. Phenolic foam spray insulation. 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. Corrosion problems when in contact with steel roofing moisture.

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 your attic to reach r 30 if you live in zones 2 or 3. The r value depends on the type of insulation its thickness and its density. The r value of some insulations also depends on temperature aging and moisture accumulation. Understanding r value thursday december 13 2018 what does r value mean.

Closed cell spray foam r values. When calculating the r value of a multilayered installation add the r values of the individual layers. R value is a measure of insulation s ability to resist heat traveling through it. Open cell polyurethane spray foam 3 5 inches thick 12 6.

As always should you have any questions or require any assistance in planning your spray foam insulation job please contact us we are always happy to help. The higher the r value the better the thermal performance of the insulation. These r values are a sum meaning this should be the total r value once you add up the entire depth of insulation. 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.

8 3 4 4 8 2 20. Expanded polystyrene foam board. A higher r value means that the insulation will do a better job of holding in conditioned air whether that s heat in the winter or cool air in the summer.