have a split level house were the second story bedrooms overhang the basement about 3ft. The problem is that the floor in this overhang area is really cold - really can tell on the wood floor in the one room, not so much on the other one with carpet. I am currently redoing my basement, so I have access to this area. Floor joist area 2x8's. It is filled with fiberglass insulation, and I did seal the one or two cracks were I had air infiltration. But still cold. Any suggestion on how to better this situation? Would spray foam insulation give a better R value than fiberglass?