From left, Ward Malisch, Ray Thompson, Larry Press, Lee Eliseian and Bruce Suprenant

St. Louis—Concrete moisture and how it affects floor coverings and related materials such as glue has become such a problem the American Concrete Institute (ACI) has issued the “Guide for Concrete Slabs That Receive Moisture-Sensitive Flooring Materials.”

The 42-page document contains materials, design and construction recommendations for concrete slabs-on-ground and suspended slabs that are to receive moisture-sensitive flooring materials.

While this has been a problem since the first concrete slab was covered with a floor, today’s fast-track construction, tight deadlines and abundance of home building products on the market has made it a major issue—and not just to the flooring industry.

A recent article by Bruce Suprenant, a noted expert on the subject, states, “Flooring failures caused by moisture may include delamination, blistering, staining and oozing of adhesives at the seams of the flooring. Such failures cause economic losses resulting from flooring removal, remediation of the moisture problem and flooring replacement. The economic loss may also include components related to disruption of services and loss of usable space.”

He later points out how, “Many such problems can be avoided during the lead up to construction if the design team consults with involved material suppliers and subcontractors in specification reviews before bidding and preconstruction meetings after the bidding.”

The ACI guide, say other experts, is a tool that can help facilitate this by bringing the various parties together.

In the works for nearly five years, the document is intended to “provide an understanding of concrete moisture behavior and drying, and show how recommended construction practices can contribute to the successful performance of floor covering materials.”

The final chapter takes what was discussed as a basis for the recommendations to improve performance of floor covering materials in contact with concrete moisture and alkalinity.

ACI notes, since the guide is specific to floor moisture problems and solutions, users should refer to the most current editions of the association’s “Guide for Concrete Floor and Slab Construction” and “Design of Slabs-on-Ground” for general prep and installation information. These two documents contain guidance on floor design and construction that is needed to achieve successful floor covering performance.

Larry Press, director of flooring for Helmitin Adhesives, and a leading advocate on the issue of concrete moisture, applauded ACI for both the guide and its efforts to help solve a difficult problem. “This is as good as it gets on the subject.

“It puts everything in a defined order,” he added, “and is based on fact, not innuendo. This is where A&D people need to look to get a better understanding of the subject and what needs to be done.”

Overall, the guide summarizes current knowledge about several subjects related to floor moisture problems and covers such topics as moisture movement in concrete, moisture and pH testing, flooring manufacturers’ recommendations, effects of many variables on the drying rate of concrete and the pros and cons of placing the concrete slab directly on the vapor retarder/barrier.

Press noted, because the guide is the first of its kind, ACI will most likely make revisions as it is circulated and opinions given. Even so, “I can’t commend ACI enough; this was a great undertaking and the organization and those involved did a tremendous job.”

The guide costs $39 for ACI members and $65.50 for nonmembers. To order the booklet or to learn more, call ACI at 248.848. 3700.