Rob writes from Ashland, Kentucky: "I have a house that has masonry walls. There is brick, a small airspace, and then block. Plaster is applied directly to the block. I am thinking about insulating these walls and was wondering if foam board alone would be enough? If so, what thickness? Or should I go ahead and build some new stud walls and use a combination of foam board and fiberglass? I don't mind doing the extra work if it will make a significant difference."

Answer: Owens Corning FOAMULAR® insulation is used alone in below-grade applications, in thicknesses of 1-1/2 to 2" (R-7.5 to R-10). For above-grade applications we recommend installing FIBERGLAS™ insulation in a stud wall. If additional R-value is needed, FOAMULAR (1" thick) can be applied over the face of the studs before the finishing material is applied.