Attic Insulation R Values Inches

Rock wool 2 8 x depth.

Attic insulation r values inches.

Fiberglass 2 5 x depth. The higher the r value the better the thermal performance of the insulation. Achieving greater r values in exterior walls. Small gray flat pieces or fibers from newsprint cellulose 3 7 x depth.

Light weight yellow pink or white. As a benchmark one inch of solid wood has an r value of 1. This calculator is to be used as an estimating tool only. 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.

Batts light weight yellow pink or white. Input depth of existing blown in insulation in inches. Dense gray or near white may have black specs. The r value is r 3 5 to r 3 6 per inch so filling a 2 4 cavity yields about an r 13.

As you can see there s some variation in r value depending on the particular type and brand of products used. It has a lower r value per inch than closed cell foam and is vapor permeable. Vermiculite or perlite 2 7 x depth. In comparison an inch of blown fiberglass insulation has an r value of 3 1 3 4 and an inch of blown cellulose in an attic has an r value of 3 2 3 7.

Here are the r values per inch of the most common types of insulation. R value of insulation by type. Click the button to calculate the approximate r value for this job. Depth inches total insulation r value.