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USG Levelrock® Brand 2500 floor underlayments are fast-applying engineered cementitious underlayments formulated and manufactured by USG for indoor use in multi-family, light-commercial and other wood-frame construction. These high-strength underlayments can be poured before drywall is installed, so they dry faster and help prevent mold by not exposing wallboard to high moisture levels. USG Levelrock® Brand 2500 engineered cementitious underlayments are also economical, as they can be applied at rates of up to 30,000 sq. ft. per day. They are formulated to provide typical compressive strengths from 2000 psi to 3200 psi at a ¾ in. minimum thickness over plywood subflooring, which meets requirements for multi-family and hotel/motel construction USG Levelrock® Brand 2500 FR floor underlayment is a fast-applying engineered cementitious underlayment formulated and manufactured by USG for indoor use in multi-family, light-commercial and other wood-frame construction. Reinforced with fibers that improve impact strength, these underlayments can be poured before drywall is installed, so they dry faster and help prevent mold by not exposing wallboard to high moisture levels. USG Levelrock® Brand 2500 FR engineered cementitious underlayments are also economical, as they can be applied at rates of up to 30,000 sq. ft. per day. They are formulated to provide typical compressive strengths from 2000 psi to 3200 psi at a ¾ in. minimum thickness over plywood subflooring, which meets requirements for multi-family and hotel/motel construction. USG Levelrock® Brand Floor Underlayment 2500 Pre-Sanded is a pre-sanded version of the 2500 product. It allows for ease in application at the jobsite. USG Levelrock® Brand 2500, 2500 Fr and 2500 Pre-Saned floor underlayments may assist in obtaining LEED credits 5.1 and 5.2..