Ro writes from Waukesha, Wisconsin: "I am in the process of finishing my basement and I have already installed plastic between the basement walls and the 2x4 studs (frame). I am getting ready to insulate the basement (no paper-back insulation) and I was wondering if is should also put plastic over the insulation between the frame and drywall (so plastic would be on both sides)? Also, I want to install insulation in the ceiling of the basement, should I put plastic over the insulation (between the insulation and drywall)?"

Answer: You don’' want to have two vapor barriers in one cavity. It is recommended that you have the vapor retarder facing towards the inside or the warm-in-winter side. Plastic may be too strong of a vapor retarder for the basement. I recommend removing the plastic and using faced insulation with the facing inside, and then covering it with a fire-rated material. If you install insulation in the ceiling, I recommend faced insulation with the paper facing towards the first floor. You can use insulation hangers to hold it in place. You usually can find insulation hangers at any place that carries insulation.