Best Way To Insulate Knee Walls

Install the knee wall.

Best way to insulate knee walls.

Steps to finishing a basement. This method can be made to work but the necessary air sealing details are demanding and fussy. There are two ways to insulate triangular attics behind kneewalls. Filling walls with a fluffy layer of fiberglass insulation is one of the easiest and least expensive ways to make your home more energy efficient.

The traditional approach is to insulate the kneewall and the attic floor behind the kneewall. In a perfect world you would be able to unscrew invisible bolts remove drywall panels install insulation and reinstall the panels our less than perfect world of permanently attached wallboard means time consuming hacking away of gypsum individually removing drywall screws or nails installing r 13 or greater fiberglass roll insulation and re installing the drywall. A job we finished last week dropped from 4060 to 2150 cfm50 just with knee wall air sealing we were able to get 8 of one wall that had no top plate. Despite all the bad publicity reflective insulation is getting lately i like to use it quite a bit on knee walls.

A better approach is to insulate the roof slope above the attic. Anytime i conduct an energy audit of a cape cod or 3 story colonial or a salt box i know that a good chunk of the homeowner conversation and audit report will deal with the knee walls. What should i keep in mind. Tip the knee walls up and fasten them to the floor.

Knee walls leak heat in at least 2 ways. 1000 2000 cfm50 reductions are fairly common with this method. Be sure to sight along its entire length to make sure it s straight. This is the obvious part especially if there is no insulation in them.

Peter wefers north andover mass. Plumb and screw the studs to the blocking for a solid wall. 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. The best way to insulate knee walls the department of energy s building america solution center recommends creating an air barrier when insulating the knee wall.

All it takes is a utility knife a straightedge and a little patience to make sure the insulation. Knee walls are among the biggest air leakage and heat loss sources in home in part because they are such a pain in the rear to insulate and air seal properly. The floor of the room with the knee wall is typically connected to the attic. This means heat especially air from the floor below flows right into the attic.

Through the floor joist.