How to Grind Imperfections in a Cement Floor

Concrete basement or garage floors, especially in older structures, are oftentimes full of bumps, high spots and the residue of decades of a myriad of spilled products. These floors can often be salvaged by grinding off the bumps, high spots and product residue using a walk-behind, electric- or gas-powered grinder. These machines are ideal for smoothing the surface of concrete and are available to rent at rental centers.

Scrapers or chisels
Broom
Shop vacuum
Walk-behind grinder
Tungsten-carbide grinder insert
Hammer
Concrete dissolving fluid
Safety glasses

Instructions

- 1
  Remove as much of the unwanted surface materials as you can manually, using scrapers or chisels. Thoroughly clean the floor surface with a broom and then vacuum it with a shop vacuum.
- 2
  Install a tungsten-carbide insert in the grinder, following the grinder manufacturer's instructions. Tungsten-carbide inserts work best for removing materials thicker than 1/16 inch.
- 3
  Turn the grinder on. Slowly lower it until the grinding surface is in contact with the floor.
- 4
  Move the grinder from side to side to keep swirl marks from forming in the cement floor. Make a couple of passes over extra-high spots to remove them and make them flush with the rest of the floor.
- 5
  Clean the grinder after finishing. First unplug it, then knock off the residue with a hammer. If the residue cannot be knocked off with a hammer, use a concrete dissolving product to thoroughly clean the grinder.

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