Dan writes from Redding, Connecticut: "I live in a log home. The house has 2" foam in the roof between the roof shingles and plywood. Not sure if it is vented. The attic floor has just 3/4 inch tongue and groove pine. If I wanted to add more insulation, could I lay foam insulation over the tongue and groove pine floor? Can you step on it if I need to go up there?"

Answer: FOAMULAR® extruded polystyrene is a sheathing insulation and is not recommended for use on an attic floor. Your local building code no doubt requires that the foam insulation be covered with a 15-minute thermal barrier, such as a flooring material, for fire safety. There are situations where unfaced Fiberglas™ insulation could be used to add R-value but this CANNOT support any foot traffic.