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 Illinois Moves Forward with College Sports’ Largest Digital Scoreboard

    The University of Illinois in Champaign, Ill., recently announced a series of upgrades to Gies Memorial Stadium that will include the largest scoreboard in college sports, according to a news release.

  • Illinois State University Breaks Ground on College of Fine Arts Transformation

    Illinois State University in Normal, Ill., recently held a groundbreaking ceremony for the Wonsook Kim College of Fine Arts transformation project, according to university news. The series of new constructions and renovations will upgrade spaces in Centennial East, the Center for the Visual Arts, and the Center for the Performing Arts, as well as replace the existing Centennial West facility with a new Commons Building.

  • Wisconsin District Breaks Ground on New Elementary School

    The School District of La Crosse in La Crosse, Wis., recently broke ground on a new elementary school that will consolidate the students and staff of two existing schools, according to local news. Funding for the school comes from a $53-million referendum approved in 2024.

  • Houston-Area High School Breaks Ground on 117,000SF Multi-Use Facility

    North Shore Senior High School, part of Galena Park ISD in Houston, Texas, recently broke ground on a new multi-use facility for student extracurriculars, according to a news release. The North Shore Multi-Use Facility will include dedicated practice and training space for the school’s athletics and fine arts programs.