How Many Inches Of Insulation Is Needed In Attic

Add the right kind of insulation when adding additional insulation you do not have to use the same type of insulation that currently exists in your attic.
How many inches of insulation is needed in attic. Achieving greater r values in attics the higher the r value the better the thermal performance of the insulation. The thicker the better. Your attic should have a certain amount of insulation in it and the recommended level of insulation for your attic is dependent on where you live. Inspecting your attic insulation.
In zone 5 the average minimum requirement for attic insulation is 11 inches of r38 fill. It is not uncommon to see 15 to 20 of insulation in a well insulated attic. If your attic insulation is only a few inches thick or if you can see the ceiling joists you re wasting money on your heating and cooling bills. The average recommended level is 17 inches of r60.
The average recommended level is 17 inches of r60. For loose fill cellulose this translates to a total depth ranging from 8 inches. Click the button to calculate the depth in inches and pounds of total insulation required for this job. Depending on type you will need somewhere between 10 and 18 inches of insulation to meet the recommended insulation values.
In zone 6 the average minimum requirement for attic insulation is 14 inches of r49 fill. This calculator is to be used as an estimating tool only. In temperate coastal areas such as zone 3 attic insulation of at least r30 up to a maximum of r60 is recommended. The recommended level for most attics is to insulate to r 38 or about 10 to 14 inches depending on insulation type.
The insulation in your attic should be at least 12 thick. Find your zone on the map and then use the chart to determine the level of insulation you need to properly insulate your attic walls floors and crawlspaces.