Viper VaporCheck, an under-slab vapor retarder, is manufactured using cross-woven polyethylene. Designed to withstand harsh construction traffic, thereby reducing the risk of punctures and pathways for water infiltration, the product is easy to install. It's available in 12x200-ft. rolls and three different thicknesses—6½, 10, and 16 mils. Insulation Solutions Inc. 866-698-6526.