How Deep Should Attic Insulation Be

For batts or rolls calculate the number based on the width and length of the product you re using.

How deep should attic insulation be.

To insulate to r value 50 with an r value of 3 5 per inch you will need 50 divided by 3 5 or about 14. Each bag lists the required depths for a range of r values and the number of bags needed to cover 1 000 square feet at those depths. For loose fill read labels. Add insulation to attic.

It is not uncommon to see 15 to 20 of insulation in a well insulated attic. The insulation in your attic should be at least 12 thick. 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. This allows you to board the attic to use as additional storage space.

Fibreglass insulation will need to be laid to a depth of anything between 8 inches and a foot. You can achieve better thermal performance in your attic by adding an. Achieving greater r values in attics. The higher the r value the better the thermal performance of the insulation.

For loose fill cellulose this translates to a total depth ranging from 8 inches. The thicker the better. Existing 3 4 inches of insulation. In temperate coastal areas such as zone 3 attic insulation of at least r30 up to a maximum of r60 is recommended.

Around a 4 inch depth of insulation will be required with the highest performing spray foam. The recommended level for most attics is to insulate to r 38 or about 10 to 14 inches depending on insulation type. Calculating thickness divide the desired r value by the r value per inch stated on the label. Inspecting your attic insulation.

First things first you need to go up into your attic inspect the condition of the insulation and calculate the current level of insulation. 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. 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.