Kevin writes from Wyoming, New York: "Recently 'gutted' my walls inside and out to replace 2x4's with 2x6's, where I then tyveked(sp?) the exterior and r-19 (pinked!) the walls. I burn wood (live in western NY) and have as yet to install a range hood. I had to remove some PINK to reroute a wire when I found damp exterior walls (from behind the PINK). I assume it's from interior dampness. I have since put up a 3Mil plastic interior barrier and have been told it's NOT a wise move. Your thoughts, suggestions?"

Answer: First, you need to find the source of the dampness. Was the housewrap taped? If there is a high moisture issue in the walls it is not a good idea to use a poly. It is too strong of a vapor barrier. Very similar to a basement wall application, you will want to use a weaker vapor barrier such as Kraft paper so the cavity can breathe somewhat.