Evaluating a concrete subfloor requires checking for both moisture content and physical flatness. Use a long level or a straight edge placed across the floor surface to identify gaps beneath the tool. Any deviations exceeding the specific product's flatness requirements must be corrected using a self-leveling underlayment or grinding down high spots. Additionally, perform a moisture test to ensure the concrete has cured sufficiently, as high moisture levels can cause adhesive failure or flooring damage.
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How do you evaluate if a concrete subfloor is sufficiently level for new flooring?
To evaluate a subfloor, use a high-quality straight edge (at least 8 feet) and a leveling tool to check for dips or humps. Industry standards generally require flatness within 3/16 inch over a 10-foot radius or 1/8 inch over 6 feet. Always verify manufacturer guidelines for specific tolerances.