Subfloor Repair, Squeaks & Floor Leveling
Floor-preparation answers around dips, humps, soft spots, squeaks, damaged panels, concrete patching and self-leveling.
How flat does a floor need to be before LVP or hardwood?
Use the exact finished-floor product's flatness requirement and measurement method. Flatness measures local deviations; level measures slope. Record where the substrate falls outside the requirement before deciding whether patching, grinding or leveling is needed.
What causes squeaks, soft spots or movement?
Squeaks can come from loose fastening, panel edges or movement between components; soft spots can indicate damaged or insufficient support. The sound alone does not identify the cause. Inspect accessible areas and refer suspected structural trouble for appropriate evaluation.
When should plywood or OSB be replaced rather than patched?
Replacement may be needed when panels have lost integrity, remain damaged or cannot provide adequate fastening and support. Minor surface defects may accept a compatible repair when the panel is sound. Identify the cause and the selected floor's substrate requirements before covering it.
When is self-leveling appropriate?
Self-leveling is appropriate only when the substrate, primer, thickness, reinforcement and finished-floor system are compatible with the selected product. It does not repair structural movement or eliminate the need to correct moisture problems. Plan containment, transitions and curing before pouring.
How do moisture and substrate conditions change floor preparation?
Moisture can affect adhesives, wood panels, concrete coatings and the flooring above them. Testing methods and acceptance criteria depend on the exact system. A dry-looking surface is not enough to establish readiness for installation.
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Turn the answers into a clear project plan
Before you call, gather your city, room sizes, current material, photos of the problem, moisture history and desired timing. Ask for a written scope covering removal, preparation, materials, installation and transitions.
Educational content updated October 2, 2026. A project estimate requires your actual scope; chat and photos do not replace onsite measurements or testing.
Technical reference starting points
Use these industry resources for deeper technical context. For tolerances, adhesives, underlayments, care and warranty conditions, the current instructions for the exact product and system being installed remain the controlling source.