Delmar writes from Masontown, West Virginia: "i have a mfg. home i want to insulate the floor i have unfaced insulation. what kind of vapor barrier do i need. do i put it toward the living space?"

Answer: We recommend using faced insulation when a vapor retarder is needed. Faced insulation typically has a Kraft paper facing. A 4 to 6 mil poly vapor retarder is commonly used if you already have unfaced Fiberglas insulation. The vapor retarder is installed toward the warm-in-winter side.