Find Concrete Products
Find a Concrete Floor Contractor
Materials and Site Preparation
Design and Construction
Special Requirements for Industrial Floors
Co-author Dan Dorfmueller
In the bad old days, concrete floors were specified without knowing how to actually measure what was being specified. The old flatness requirements of ¼ inch in 10 feet, for example, left so much up to interpretation that it was basically useless. Anyone could measure almost any floor and pass it or fail it depending on how the measurement was applied and what they wanted to happen. Can't you just see a poorly trained testing technician with an old warped 10-foot long 2x4 bending down with a ruler to measure the gap between the straightedge and the floor? Then saying, this floor is no good! But, today we have F-numbers for flatness and levelness and ACI 302.1R, Guide for Concrete Floor and Slab Construction, that tells us when and how to apply the F number specifications.
Concrete floors, whether used in a residential basement, a big-box store or a manufacturing plant, are basically the same. In commercial or industrial settings, though, the slabs usually have special requirements based on the loads or flatness or levelness required. To get a slab that meets these requirements, the contractor will use special techniques in placing and finishing the concrete. Commercial or industrial floors can also have special requirements for surface hardness, finish, and even color. Wal-Mart, for example, has a specification for their exposed concrete floors that incorporates color, surface densifiers, and a hard troweled finish. That company has high expectations for everything and their concrete floors are no exception.
Commercial / Industrial (C/I) floors can be built on grade or can be suspended. Suspended floors are often built on metal decking, which is corrugated sheet metal supported by structural steel. Achieving high flatness and levelness values on these floors can be difficult since the decks and frames deflect under the weight of the concrete.