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

  • Round Rock ISD Completes New Early College High School

    Round Rock ISD near Austin, Texas, recently announced that construction is complete on a new, 46,500-square-foot campus for Early College High School, according to a news release. The new facility will allow the school’s students and staff to move from portables into a permanent building and increase its enrollment to 500.

  • Pitzer College

    Designing for Change in Higher Ed Learning Environments

    Higher education will continue to evolve, and learning environments must evolve with it. By prioritizing adaptable infrastructure, thoughtful reuse, strong energy performance, and wellness-centered design, campuses can create spaces that support learning today while remaining flexible for the future.

  • textured paper collage shows a school building on fire as a fire truck sprays water into the flames

    Why a Fire Loss Is More than Flames

    We've all seen what fire damage can do to a property, but the types of damage building owners often encounter after a fire loss can exceed expectations. Having full awareness of the different forms of damage properties can sustain helps owners respond faster, reduce continued damage, and get back on the road to recovery in short order.

  • LSU Breaks Ground on $200M Residential Project

    Louisiana State University in Baton Rouge, La., recently broke ground on a new residential complex, according to university news. The South Quad residential project will consist of two buildings and add a total of 1,266 beds for freshmen students. The development comes with a price tag of $200 million, and it’s scheduled to open to students in fall 2027.

Digital Edition