A vapor barrier is essential to stop water vapor from the soil from penetrating through your basement and crawl floors and walls. Vapor barriers of polyethylene have been used as a vapor retarder for some years now, but it has limitations. Newer high performance, high density polyethylene sheeting is the key to stopping water vapor from finding its new home in your wood floors, insulation, or carpeting.
Vapor barriers used beneath ceramic tile are not ordinary plastic poly vapor barriers. These high performance vapor barriers keep water out with two layers of materials. Here are some vapor barrier manufacturers.