How to Level a Floor With an Uneven Subfloor
- 1). Sink spiral screws everywhere on the subfloor where you detect any movement of the plywood sheets using your screw gun.
- 2). Vacuum the floor, getting all debris out of any cracks or gaps in the surface. Clean the floor with floor cleanser. Let it dry for at least 48 hours.
- 3). Set the board on its long, narrow edge at one end of the room. Move the board slowly over the floor looking for gaps indicating low spots. Mark the low spots with your pencil. Cover and mark the whole floor.
- 4). Pour liquid leveler slowly over each gap, space and low area in the subfloor, beginning at the furthest point from the doorway and working your way out of the room. Run your board over the compound to flatten it where necessary.
- 5). Let the leveler set overnight. The subfloor is ready for top-flooring.
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