Insulating an attic floor and ceiling
Ok. We all know this is a no no, because of the risk of the attic temperature going below the dew point.
I’m curious what happens if you apply say R-5 of foam to the underside of a roof, while leaving your attic floor at R-50.
wood itself has some R value, so clearly there is some R at which there is too much insulation.
saving this, if you just air sealed the ceiling without insulating say with this:
it would still make the thermal envelope more airtight.. but would it have any negative moisture effects in the attic?
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