Just a couple of notes. I hope your builder did insulate. It sounds
more likely that there is insulation, but he did not do his job with the
heating system and under estimated the load on the bedroom. I think you
will find the fix there.
If you find you do not have insulation in the floor, the vapor barrier
goes toward the bedroom (heated space) and remember that the finished
ceiling is not just for looks, it is there as a fire barrier and you must be
sure to replace it and seal it and use fire rated drywall (generally 5/8" is
called for I believe)
Joseph E. Meehan
26 + 6 = 1 It's Irish Math
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