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Installations over Gypcrete

           Installations over Gypcrete



The purpose of the information is to outline ideal flooring options and applications over Gypcrete.

Gypsum concrete is a building material used as a floor underlayment applied over wood subflooring and concrete. Gypsum concrete usage in the industry started in the 1980s due to the advantages over standard heavy concrete. The brand name Gypcrete; a Maxxon Corporation trademark has become used universally as the term for gypsum concrete by construction professionals and architects. It's used extensively in condominium, apartment and hotel constructions for sound reduction, fire resistance, radiant heating and floor leveling. It is a mixture of gypsum, Portland cement and sand. Gypsum concrete is ultra-light weight. 

As a substrate or sub-base for flooring materials Gypcrete has advantages and disadvantages. Due to the stated composition of Gypcrete the total surface area is inherently light-weight, gritty and dusty, subject to fracture under installed floorings.  In addition, many adhesive companies require a minimum compressive strength of concrete to be a minimum of 2,000 psi for gluing engineered hardwood installations or a minimum compressive strength of 2,500 psi for gluing solid hardwood installations, for which Gypcrete would not qualify. Verify with the flooring and adhesive manufacturer if a particular style of engineered flooring can be glued to Gypcrete and if "dust inhibiting sealers" or "surface primers" are required. Note that all "floating" floors like Laminates or engineered are ideal products for this application.

Traditional solid wood "naildown" products have never been recommended over Gypcrete. Gypcrete is not a suitable nailing base to attached wood floorings

At present, customers desiring a solid wood installation over Gypcrete substrates can install a floating plywood subfloor over the Gypcrete to be used as a secure nailing base.

Installation questions or comments please contact the Technical and Installation dept.