Skip to main content
Add as a preferred source on Google

Concrete Slab Configuration Raises Concerns Among Sports Flooring Installers

  • 01/23/18

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 Tennessee at Chattanooga Launches New Emergency Communications System

    The University of Tennessee at Chattanooga (UTC) recently deployed a new emergency notification and incident management system for its campus, according to a news release. The university partnered with 911Cellular to launch Safe@UTC, a smartphone app allowing university officials to communicate and respond during emergency situations.

  • Spaces4Learning Trends & Predictions for Educational Facilities in 2026: Part II

    As education leaders look toward 2026, the design of K–12 and higher education facilities is being reshaped by powerful, converging forces. Survey respondents point to the rapid growth of Career and Technical Education, deeper alignment with workforce and industry needs, and the accelerating influence of AI and emerging technologies.

  • University of Arizona Approves New Residence Hall

    The Arizona Board of Regents recently approved plans for a new residence hall at the University of Arizona in Tucson, Ariz., according to a news release. The new facility is scheduled to open in fall 2028 and have the capacity for more than 1,200 students, enforcing a new university expectation that all first-year students live on campus.

  • How a Portable Sink Helped an Art Classroom Run More Smoothly

    Classroom design decisions can have outsized effects on instructional time and safety at schools juggling mismatched infrastructure, strict budgets, and crowded schedules — particularly in the arts. Between spilled paint and dirty brushes, art classes run smoother with a sink in the studio. But many schools don’t have a sink in every art classroom.