Concrete Slab Configuration Raises Concerns Among Sports Flooring Installers

OAKBROOK TERRACE, IL – Concrete slab configuration is very important in the success of a new maple floor installation.  Placing a below-slab vapor barrier directly beneath the concrete slab is proper and typical.  Placing any type of fill material between the below-slab vapor barrier and the concrete slab frequently causes moisture-related problems with the finished maple surface.

The Maple Flooring Manufacturers Association (MFMA) requires the general contractor to provide a concrete slab troweled smooth and flat to a tolerance of 1/8 of an inch in a 10-foot radius, subject to the approval of the MFMA wood flooring contractor. By placing sand between the vapor barrier and the slab, a flatter concrete slab with less initial curling can be produced.  However, this configuration allows the sand to act like a sponge—trapping moisture within the sand layer during the concrete pour. Over time, trapped moisture can migrate up through the concrete slab and cause moisture-related difficulties with subfloor components and the finished wood flooring surface.

The only MFMA-recognized method for reading concrete moisture levels within a slab is by testing its relative humidity. Please refer to the instructions of the manufacturer’s relative humidity test kit for complete details on how to administer the test correctly. MFMA recommends the relative humidity level for a concrete slab for a non-glue-down maple floor system be 85 percent or lower and for glue down systems the concrete slab relative humidity level should be 75 percent or lower before installation.For concrete relative humidity conditions above MFMA’s recommendation consult your MFMA Sport Floor Contractor or your MFMA Manufacturer.

For more information regarding variations to MFMA’s recommended concrete slab configuration, please contact MFMA’s technical director at 888/480-9138 or email [email protected].

Featured

  • University of Washington Opens New Broadcast Studio

    The University of Washington in Seattle, Wash., recently announced the opening of Sundodger Studios, a new broadcast, production, and content facility, according to a news release. The university partnered with Anthony James Partners for the design and development of the studio, which will host about 100 live broadcasts and 120 live videoboard shows per year.

  • California District Breaks Ground on Major Campus Renovation

    Alameda Unified School District (AUSD) in Alameda, Calif., recently announced that construction has begun on a major campus overhaul for Otis Elementary School, according to a news release. The district partnered with Quattrocchi Kwok Architects (QKA) and Lathrop Construction Associates, Inc., for its design and construction, respectively.

  • Georgia State University Opens New Research Tower

    Georgia State University in Atlanta, Ga., recently held a ribbon-cutting ceremony for a new, nine-story, 155,000-square-foot Research Tower, according to university news. Amenities include academic classrooms, a large lecture space, teaching labs, faculty research space, and the uppermost floors reserved for future expansion.

  • Fayetteville State University Opens New College of Education Building

    Fayetteville State University (FSU) in Fayetteville, N.C., recently celebrated the opening of a new $69.3-million College of Education building, according to a university news release.