Band joist insulation in a retrofit.
We know the band joist of an older platform framed home is a thermal weakness. Often un-insulated, often leaky.
During the course of an air sealing and insulation retrofit, is it typically cost effective to cut into the perimeter of the first floor ceiling in order to access this weak point? With access, spray foam or dense packed cellulose could be applied in order to seal and insulate this portion of the wall assembly.
Will accessing and addressing this area lead to substantial CFM50 reductions and thermal improvements to the home?
My gut tells me that this portion of the assembly is probably right near the neutral pressure plane, and that real world air infiltration is probably not a huge problem at this location.
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