Knee Wall Storage Insulation

If the attic is not insulated insulate the attic rafter.

Knee wall storage insulation.

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. The sloped roof creates a small space that can hardly be use. Rather than leaving this space empty homeowners can fill it with insulation for additional thermal protection. While they can be an ideal storage spot knee walls can t do much without being properly insulated fiberglass is layered down on the floor of the knee wall but since fiberglass doesn t stop airflow it doesn t do anything to insulate the area.

If you go back and view the illustration above you ll notice there s an enclosed area behind the knee wall. 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. Blown insulation in the knee wall and top attics. We reduced the air leakage nearly 50 on this house in shaker heights without insulating the walls.

Screw two support braces to the attic floor right behind the knee wall. Walls the junction of the top plate and top of exterior walls should be sealed. R402 4 1 1 n1102 4 1 1 air barrier and insulation installation table. Added bonus the floor of this knee wall leaked too so there is a line of foam just above the floor joist.

Also be sure to remove any insulation. We prefer cellulose but we use fiberglass sometimes too. 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. Exterior thermal envelope insulation for framed walls should be installed in.

Step 9 insert dresser photo by. The knee wall storage unit must be insulated similarly to the attic space or the room will suffer from infiltrating air leaks. Then cover that same area with an r 8 fsk affixing it using cap nails. Step 8 install supports photo by geoffrey gross.

Use a hammer to remove any knee wall studs from the opening. Knee walls also provide pockets for additional insulation in the attic. Build the supports out of 2x4s making sure they re flush with the sill of the cutout. In tight attics or odd shaped wall conditions i e.

Kneewalls short walls under sloped ceilings are common in story and a half homes and in bonus rooms above garages.