concrete 2nd floor slab in or out of thermal envelope?
Hello all! I’ve just received a gift subscription to this site, and am very interested to read the various articles.
I’m planning new construction of a metal frame building. It will be workshop/garage on the ground floor, residence on the 2nd floor. The structure of the mezzanine is metal joists, a metal deck, and a concrete slab poured onto the deck. The deck + slab is 6″ thick (not yet clear to me how thick the concrete is). The building will be near Lake Tahoe California, climate zone 6.
My question is: is it better to put insulation on top of the concrete slab, and flooring on top of that? Or better to insulate beneath the metal deck, so as to have that floor mass inside the heated envelope of the building? The workshop will be heated enough to keep from freezing, but I’m expecting to go most of the winter with a thermostat set to 50 F.
My thought is that it might lend more thermal stability to the residence to have the mass of the floor structure inside the insulated envelope of the residence, and improve comfort.
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