New LEVELROCK Brand Floor Underlayment RH (Radiant Heat) from the Industrial Products Division of United States Gypsum Company is specially formulated to deliver long-term strength and superior heat transfer performance for radiant floor heat systems. The poured gypsum concrete product delivers compressive strengths between 2,500 and 3,200 psi and is designed to maintain that strength for the life of the floor. LEVELROCK Brand Floor Underlayment RH is not subject to powdering, chalking or cracking, all of which can result in loss of heat transfer performance. It is suitable for use with hydronic and electrical systems. The non-shrinking formulation of the underlayment locks tubing in place, preventing noise and tube chafing. The product weighs 14.4 pounds per square foot (when applied to a 1 1/2- inch thickness) and has a dry density of only 115 pounds per cubic foot. Its light weight makes it a practical choice for wood-framed single- and multifamily construction, as well as light-commercial applications. The underlayment can be applied over a variety of subfloors, including plywood, OSB (oriented strand board), heavy wood plank, concrete and concrete plank. It can be covered with a variety of floor coverings, including ceramic tile, carpeting and wood. www.usg.comUnited States Gypsum Company.