Insulate Attic Knee Walls

There are as many ways to do it as there are people who do it.

Insulate attic knee walls.

If you re insulating an attic the knee walls are important. The traditional approach is to insulate the kneewall and the attic floor behind the kneewall. They are short walls usually no more than 3 feet high used to support the rafters in roof construction with attic space behind them. The best materials for the attic and thus the knee wall are spray foam fiberglass and cellulose.

A better approach is to insulate the roof slope above the attic. One of the best methods is rigid foam board with sealed joints over insulation in the knee wall. When it comes to insulating knee walls you will want to insulate this space using the same material and method as the rest of your attic. Insulating only the attic roof rafters and the walls at the end of the attic is one method some use to insulate the knee wall area underneath but carson dunlop author of principles of home.

There are two ways to insulate triangular attics behind kneewalls. If you plan to insulate the roof deck of your attic then you would use spray foam or fiberglass batts. This is not very easy in most of the older houses we work on because the hatches and attics are too small to get rigid foam board through.