- 1). Clean the floor with cleanser and a scrub brush. Rinse well. Let it dry for a full day.
- 2). Lay your 2-by-4 on its narrow edge at one end of the room. Pull it slowly over the floor, watching the line where the board meets the floor, looking for low spots, which will be visible as gaps between the floor and the board.
- 3). Use a pencil to mark around the areas with the low spots. Mark the entire floor.
- 4). Pour a few inches of water into your bucket. Add floor-leveling compound in the ratio recommmended on the leveler package; it will vary by brand and elevation. Mix well with your drill and mixing bit. The mix should have a thin, soupy consistency.
- 5). Pour the leveler slowly over each low area that you marked, letting it even itself out. Also fill any gaps or holes in the surface. Work from the far edge of the room, away from the door, so you can back out without walking on the fresh leveler.
- 6). Allow the leveler to set for 12 hours. The subfloor is now ready for flooring.
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