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USG Levelrock® Brand 3500 Green floor underlayment is a are high-quality, versatile engineered cementitious underlayment for indoor use in light-commercial and renovation construction. It can be easily applied over wood and concrete subfloors at a thickness of up to 3 in. Its high compressive strengths at low thicknesses provide superior underlayment performance for higher-traffic areas and minimize floor damage from trades. High production rates, lightweight with high compressive strength and fire resistance make USG Levelrock® Brand 3500 Green floor underlayments ideal alternatives to lightweight concrete floor applications. USG Levelrock® Brand 3500 Green floor underlayment is made with recaptured gypsum, from the flue gas desulfurization of the process used to clean combustion gases from fossil-fuel-burning power plants. This process is used to greatly reduce emissions of sulfur dioxide which helps the environment by reduction of harmful acid rain. The use of this recaptured gypsum also eliminates the need to dispose of the material in landfills as a solid waste. USG Levelrock® Brand 3500 Green floor and 3500 Green FR underlayments may assist in obtaining LEED credits 5.1 and 5.2. USG Levelrock® Brand 3500 Green FR floor underlayment is a high-quality, versatile engineered cementitious underlayment reinforced with fibers that improve impact strength. A cost-effective solution for indoor use in lightcommercial and renovation construction, USG Levelrock® Brand 3500 Green FR engineered cementitious underlayment can be easily applied over wood and concrete subfloors at a thickness of up to 3 in., and can be applied to concrete surfaces without mechanical profiling. High compressive strengths at low thicknesses provide superior underlayment performance for higher-traffic areas and minimize floor damage from trades. High production rates, lightweight with high compressive strength and fire resistance make USG Levelrock® Brand 3500 Green FR floor underlayment an ideal alternative to lightweight concrete floor applications. USG Levelrock® Brand 3500 Green and 3500 Green FR Self-Leveling Underlayments may assist in obtaining LEED® credits 5.1 and 5.2.