Sealing/Insulating Attic with Knee Wall
I know there’s a recent Q&A thread about an attic in a relatively new construction. My question is more specific. Picture a home with multiple attic spaces. The space with the air handler is a side attic on the 2nd floor. The cross section on the attic is shaped like a right triangle, with the base being over the 1st story conditioned space and outside porch, the left vertical side being a wall to conditioned 2nd floor space, and the hypotenuse being the roof. There’s a knee wall of sorts that sits on the exterior first floor wall dividing conditioned space from porch. If I were to turn my attic into conditioned space to reduce the HVAC load, I could reduce the materials cost of the project by starting the attic sealing/insulating at the knee wall. My question is the order and orientation of material application. Do I install an R Matte Plus 3 with foil side facing the porch side or the HVAC (to be conditioned) side of the knee wall studs, and which side of the studs should I attach it, assuming I’ll be putting fiberglass batts between the knee wall studs?
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