Insulating A Finished Attic With Knee Walls

Insulating the floor and kneewall requires more careful air sealing but is sometimes easier to insulate since you can use blown insulation.

Insulating a finished attic with knee walls.

If only the living space will be insulated wrap the insulation around the room s walls and ceiling and then continue along the floor of the non living space. Added bonus the floor of this knee wall leaked too so there is a line of foam just above the floor joist. 2d extend insulation into joist space to reduce air flows. Kneewalls short walls under sloped ceilings are common in story and a half homes and in bonus rooms above garages.

We reduced the air leakage nearly 50 on this house in shaker heights without insulating the walls. Although kneewalls can help turn attics into living space they often present insulation challenges most builders install fiberglass batts between the studs and some type of blown insulation between the floor joists. How to insulate knee walls. Despite all the bad publicity reflective insulation is getting lately i like to use it quite a bit on knee walls.

In this case the area behind the knee wall will be uncomfortably hot or cold. We prefer cellulose but we use fiberglass sometimes too. In finished attic rooms with or without dormer insulate 2a between the studs of knee walls 2b between the studs and rafters of exterior walls and roof 2c and ceilings with cold spaces above. Insulate across the top of flat attic.

Unlike traditional walls with two finished sides. If you want the attic to be outside then using foamboard on the attic side of the knee wall is a good idea. Blown insulation in the knee wall and top attics. There are two basic ways to insulate a finished attic.

1a attic access door. Knee walls are half walls built into areas where a full sized wall will not fit such as finished attic crawlspaces.