Attic Insulation R Value Depth

R value is a measurement of thermal resistance and measures the ability of heat to transfer from one side of an object to another.

Attic insulation r value depth.

Insulation depth depending on your climate energy codes require varying r values for ceiling insulation. Add the right kind of insulation. There are many ways to retrofit a home with fiberglass and. You can achieve better thermal performance in your attic by adding an additional layer of insulation.

You will need a higher r value of insulation if you live in the northeast than if you live in southern california. Achieving greater r values in exterior walls. The recommended level for most attics is to insulate to r 38 or about 10 to 14 inches depending on insulation type. Click the button to calculate the approximate r value for this job.

Your home s age if your home is more than 10 year old you likely need more insulation. In temperate coastal areas such as zone 3 attic insulation of at least r30 up to a maximum of r60 is recommended. Recommended insulation levels for retrofitting existing wood framed buildings. But newer homes in central and southern arizona are insulated to ratings of r 30 to r 38 while newer homes in northern arizona generally have attic insulation at r 60 because of colder winters.

This calculator is to be used as an estimating tool only. To get the target r value from the product you chose use the number of bags your calculations showed that you needed to insulate your attic never fewer. Input depth of existing blown in insulation in inches. Where you live different climates require different insulation r values.

Loose fill fiberglass has an r value of r 2 2 to 2 7 per inch3. If you ve reached your target depth but still have a few bags left over keep adding the material at an even depth throughout the space until all the bags your calculations called for are empty. The r value of loose fill cellulose is r 3 2 to 3 8 per inch2. Achieving the desired r value depends on both the depth of the insulation and its density.

For loose fill cellulose this translates to a total depth ranging from 8 inches. The higher the r value the better the thermal performance of the insulation. 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. R value is a measure of insulation s ability to resist heat flow.

Existing 3 4 inches of insulation.