Visqueen is a plastic sheeting material made from polypropylene. It is nonporous and commonly used as a damp proof membrane to protect concrete from ground moisture. It is also used to make cheap tarps and bags.

Visqueen is a trademark of Tredegar.

Sources: http://isecco.org/glossary/glossary.html, http://moisturetesting.com/, http://shop.store.yahoo.com/cinemasupplies/tarps.html
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