When insulated and covered with drywall the walls improve the thermal envelope of an attic.
Attic knee wall construction.
Framing basics for attic knee walls along the sides of your loft or attic space.
If you aren t sure whether or not your attic contains knee walls go and look around the edges.
Install a top and bottom plate or blocking at the top and bottom of all knee wall cavities.
What are knee walls.
A knee wall is a short vertical wall roughly two or three feet high that blocks in that useless triangular space.
Determine the angle of rafters by setting the scrap piece of 2x4 in a vertical position against the side of a rafter.
Support and follow me.
The higher the knee wall the greater the amount of useful wall space you create in your finished attic.
The knee wall will be built on the floor of the attic and then tipped into place against the rafters.
Scribe a line on your scrap piece along the angle formed by the rafter.
Install insulation without misalignments compressions gaps or voids in all knee wall cavities.
In most instances they are no taller than 3 feet but some builders may custom fit them according to the roof s shape and size.
Knee walls are short usually wooden walls installed around the sides of an attic where the rafters meet the floor.
Install an air barrier on the exterior of attic knee wall insulation and to block open floor joist cavities under attic knee walls.
You can see the image below for an example of a knee wall.
One of your 2x4s will act as the bottom of your wall and will not be cut.
Knee walls are short wood framed walls that install between the ceiling joists and rafters in an attic.