How to Level a Wood Subfloor for Laminate Flooring
- 1). Place an 8-foot-level on the sub-floor to check for any areas where the floor contains dips or bumps. Mark these areas by drawing an outline around the dip or bump with a piece of white chalk.
- 2). Sit the tip of a nail set on a protruding nail head. Use a hammer to sink the protruding nail head under the level of the wooden sub-floor. Repeat this process for any additional nail heads that protrude up above the surface level of the wood sub-floor. Nails that stick up above the surface of the wood sub-floor may cause damage to the floor sander, resulting in an expensive rental fee or replacement floor sander.
- 3). Attach a sanding pad to a floor sander. Turn the floor sander on and glide the machine over the wood sub-floor to remove any sealants or coatings. Concentrate the floor sander on high spots or bumps you may have outlined with the pencil. Make sure you stop the floor sander when the high spots become level with the surrounding wood sub-floor.
- 4). Use a handheld edging sander to sand the perimeter of the wood sub-floor or other areas where the floor sander could not reach.
- 5). Vacuum the sanding dust from the wood sub-floor with a shop vacuum.
- 6). Walk the entire surface of the wood sub-floor to check for squeaking or loose boards. Hammer nails into the loose or squeaky boards to secure them to the floor joists.
- 7). Roll strips of underlayment over the entire wood sub-floor. Extend the underlayment up the wall an extra 2 inches for both ends of the strips.
- 8). Butt the edges of the underlayment together and use duct tape to secure them.
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