How Thick Should Insulation Be In An 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 thick should insulation be in an attic.

The thicker the better. 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. Achieving greater r values in attics the higher the r value the better the thermal performance of the insulation. The insulation in your attic should be at least 12 thick.

They range from around 1 to 3 inches in thickness and can be used in multiple applications ranging from walls to attics. It is not uncommon to see 15 to 20 of insulation in a well insulated attic. First things first you need to go up into your attic inspect the condition of the insulation and calculate the current level of insulation. The most common form that insulation comes in is a batt or blanket these are large rolls of insulation that are easy to cut into usable shapes.

For loose fill cellulose this translates to a total depth ranging from 8 inches. The recommended level for most attics is to insulate to r 38 or about 10 to 14 inches depending on insulation type. So if the ideal r value for your home is r 40 your contractor may only need to spray five inches of foam insulation. This is compared to having to stack fiberglass as high as 14 16 inches to get the same results.