USG Corp. and Shaw Industries have completed joint testing of gypsum-based underlayments. The multi-year testing and assessment has resulted in modified installation specifications as well as rehabilitation guidelines based on a better understanding of the entire floor covering system, according to the companies.

“Through our partnership with USG, we have learned a great deal about gypsum floors,” said Julie Brumbelow, director of technical support at Shaw. “There are products available today that are far superior to those used in the past.”

Shaw’s approved gypsum-based underlayments must meet a minimum compressive strength of 3,000 psi for carpet, resilient and hardwood floor coverings. Shaw also supports USG’s “Rehabilitation Guidelines for Damaged Gypsum Underlayments.” These guidelines provide a way to repair existing damaged or compromised gypsum underlayments while maintaining building code requirements based on ASTM E119/UL 263 standards for fire resistance.

“We have worked hard over the years to remove the stigma associated with gypsum-based underlayments and appreciate Shaw’s willingness to collaborate with us through this lengthy process,” said Ray Kaligian, director of advanced technologies for performance flooring at USG. “Ensuring that floor covering manufacturers recognize the high standards we place on our products is key to advancing gypsum-based solutions. We’re incredibly proud of what we have accomplished not only for ourselves but also for the entire gypsum industry.”

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