Subfloor suitability is defined by four core requirements: structural stability, flatness, surface cleanliness, and moisture management. For hard surfaces, the subfloor must support the load without excessive deflection or sagging. Flatness is usually measured using a 10-foot straightedge, where deviations must not exceed industry-standard tolerances. The substrate must also be thoroughly cleaned of debris, paints, or sealants that might interfere with mortar adhesion, and verified to be structurally sound before any installation begins.
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What criteria define a suitable subfloor for different flooring types?
A suitable subfloor must be structurally sound, clean, dry, and level to within the manufacturer’s specified tolerance. It must be free of deflection, movement, oil, grease, or contaminants that could prevent a proper bond for the chosen flooring type.