Industry Members Endorse ASCC Position Statement on Floor Flatness Tolerances

Ps 6 Floor Flatness 03 2014 Med
American 10452221

Three additional national associations, the International Union of Bricklayers and Allied Craftworkers, the Tile Contractors Association of America, and the International Masonry Institute, have endorsed a Position Statement on floor flatness tolerances written by the American Society of Concrete Contractors (ASCC). The position statement had previously been endorsed by the National Wood Flooring Association and the Flooring Contractors Association. Members of all seven associations will use the document to help resolve this ongoing construction issue.

The statement explains that flooring contractors (Division 9) and concrete contractors (Division 3) measure floor flatness by different means. In addition, floor flatness changes with time, due to a process called curling. Curling makes it impossible to predict what the flatness of a slab will be when the floor coverings are installed.

The solution to this, the associations agree, is for the owner to provide a bid allowance, established by the designer and based on the floor covering requirements, for grinding and patching necessary to close the gap between Division 3 tolerances and Division 9 tolerances.

“The difference between how Division 3 and Division 9 measure floor flatness, and the changes that occur in a concrete slab between pouring and the time the floor covering is applied, have been the source of many arguments, much misspent time and numerous lawsuits,” says Bruce Suprenant, technical director of ASCC.

“We believe an allowance in the bid would accomplish two things,” says Suprenant. “First, it would cover the cost of the patching and grinding that is almost always required. Second, it brings the issue to the attention of the owner and designer early on, hopefully forcing them to acknowledge that the point in question does in fact exist.”

“Many members of the ASCC have successfully used this Position Statement to drive home this point with owners,” says Mike Poppoff, president of the ASCC. “We believe a joint statement from Division 3 and Division 9 contractors will carry even more weight. The intent of all seven organizations is that it will be used to make the construction process go more smoothly for all involved.”

The Floor Flatness Position Statement may be downloaded at

For more information, visit or call the ASCC office at (866) 788-2722.