A quiet living space is our business. Hacker Industries, Inc. offers a full line of FIRM-FILL® Sound Control Mats (SCM) and pourable FIRM-FILL® Gypsum Concrete Underlayments (GCU) to meet demanding sound-attenuating specifications and are listed in over 105 UL fire-rated designs. FIRM-FILL® SCM and GCU are the ONLY underlayment products featuring up-to-date published reports from both the IIC (IIC-ES 3386) and IAPMO (UES-474). Technical product evaluations for code compliance by organizations such as ICC – ES and IAPMO provide peace of mind to code officials, architects, general contractors, specifiers and developers. FIRM-FILL® SCM are durable, lightweight sound control mats that are engineered to limit impact sound transmission between units when used in conjunction with FIRM-FILL® Brand Gypsum Underlayments. FIRM-FILL® SCM can improve IIC ratings 15-25 points and carry a Class-A fire rating under ASTM E84.   All FIRM-FILL® Gypsum Underlayments are quick drying and offer a flat, durable surface for finished floor coverings. They meet ASTM F2419; Standard Practice for the Installation of Thick Poured Gypsum Concrete Underlayments, as well as Los Angeles City RR 24540.  Established in 1983, Hacker Industries, Inc. is recognized nationally for its quality products, exemplary customer service and affordability. More than three billion square feet of FIRM-FILL® (SCM) and Gypsum Concrete Underlayments have been installed in residential, multi-family, and commercial projects across North America, demonstrating proven performance over plywood, OSB, corrugated steel deck, concrete or any structurally sound substrate.