Knee Wall Insulation Foam Board

Owens corning foamular 250 extruded polystyrene xps rigid foam insulation is a closed cell highly moisture resistant rigid foam board well suited to meet the needs for a wide variety of residential and commercial construction applications.

Knee wall insulation foam board.

Added bonus the floor of this knee wall leaked too so there is a line of foam just above the floor joist. Rake walls it s easier to handle than plywood or thermo ply and still gives you an r 19 r121 assembly. This method of insulation won t work if the triangular attic includes ducts or plumbing pipes. We prefer cellulose but we use fiberglass sometimes too.

Some of the most reviewed foam board insulation are the silverboard 24 in. R5 radiant acoustic insulation kit stc 19 5 piece with 172 reviews and the amvic multipurpose high density insulation kit r10 2 3 8 in. Blown insulation in the knee wall and top attics. For example rigid foam board can act as both a thermal barrier and an air barrier across the unconditioned side of the knee wall.

In tight attics or odd shaped wall conditions i e. Some insulation options either do not provide air sealing or are difficult to install outside of the wall framing. The disadvantage is that it would be very very hard to reach the desired r value from r 49 to r 60 depending on climate for attic insulation. We reduced the air leakage nearly 50 on this house in shaker heights without insulating the walls.

An insulated kneewall is effectively an exterior wall so you ll need a layer of rigid foam drywall osb or thermoply on the back side of the kneewall to prevent cold air from degrading the performance of the insulation. The advantage here is that your knee wall is probably already insulated this way so it s just a matter of buying some foam so cheap.