How to Level a Sloping Floor

Cement or Concrete

• 1

  Mop the floor with clear water to remove dust and dirt. If the floor surface has greasy spots, use an anti-grease soap with the water to pull up the grease. Allow the floor to dry completely.

• 2

  Apply standard leveling compound, also known as concrete patch, to slopes that create only small dips of a four to five inches or less. Use a putty knife and remove extra leveling compound from the floor by scraping the knife edge across the surface. Sand the compound down once it dries to make sure it sits level and clean the floor again with a wet mop.

• 3

  Pour a bucket of self-leveling compound over the floor surface in the area of the slope if many dips appear in the floor or if the slope is extreme. Use a rake to drag the self-leveling compound across the floor’s surface to spread it somewhat evenly. Allow the self-leveling compound to settle for the time the packaging recommends and it automatically levels out on the floor.

Wood

• 4

  Use a hammer to pull out the nails in the the floorboards of a sloping floor made out of wood. Remove the floorboards in the areas where the sloping occurs.

• 5

  Lay a 4-foot level along the joist beneath the floorboard in the area where the floor slopes to determine where the slope occurs on the joist. If the joist lies mostly level, but one area of the joist sits higher than the rest, sand that area of the joist down a little bit at a time, stopping to check the joist regularly with the level, until the joist sits flat.

• 6

  Cut a wood strip to add to the top of the joist if the majority of the joist sits level, but one section of the joists dips down to create the slope. Use a block of wood the same height and width as the original joist and set the block of wood right next to the joist. The new joist should sit slightly higher than the old joist in the area of the slope.

• 7

  Trace along the slope of the old joist to draw a guideline onto the new joist. Cut along this line on the joist with a circular saw to create the angled wood strip for the joist.

• 8

  Attach the wood strip to the joist with liquid nails, placing bricks or blocks on top of the new piece of wood to hold it down on top of the strip. Leave the joist to dry for the time recommended on the adhesive packaging. Remove the bricks or blocks and nails the floorboards back into place on the repaired joists.