Beth writes from Perrysburg, Ohio: "We have a 'bonus room' in our house that is freezing in the winter, roasting in the summer. One wall is interior to the home; one wall is exterior with a window. The problem is the north and south walls. They have small (3') doors that open to attic space. There is some insulation in there, but not much. The horizontal surface has some pink insulation, some blown insulation, and the vertical surfaces facing the room have foam insulation. We bought a bunch of unfaced insulation; where do we put it?? If we put it on the vertical parts, can we staple it up since there is already foam there?"

The unfaced insulation you purchased can be placed on the floor of the attic space behind your knee walls and it can be placed in the walls themselves if you don't already have insulation in them. If the walls are already insulated, I suggest placing rigid foam insulation over the studs. This will do a couple of things to help reduce heat transfer through the wall. First, it reduces the amount of air infiltration, and second, it reduces the heat transfer through the framing. If you still have problems after insulating you may want to look at the HVAC system. Most bonus rooms tend to be either hotter or colder due to the extra exterior surfaces.