The Barrier acts as a thermal barrier, vapor barrier, moisture barrier, and radon barrier, all in one. It is made with recycled, extruded polystyrene and heavy-duty black polyethylene film (less than an inch thick), laminated on both sides and with patented seamless self-taping edges. It can be used under slabs, basements, foundations, crawl spaces, pools, hot tubs, and mobile or modular homes. It also deters carpenter ants, termites, and other insects. Barrett Enterprises Inc. 877-904-8424.