How to Patch a Cement Floor Before Tiling
- 1). Use a hammer and chisel to level the bottom and even out the tapered sides of the hole in the concrete. Cement won't adhere well to uneven or feathered surfaces. Wear goggles to protect your eyes from flying chips of cement.
- 2). Remove large chips by hand. Vacuum the area to remove small chips and cement dust. Scrub the hole with water and a stiff brush.
- 3). Apply a liquid concrete bonding agent to the hole with a paintbrush.
- 4). Mix a small amount of cement according to the manufacturer's instructions. Scoop it into the hole with a trowel. Work cement into all the ridges and corners of the area that needs patching. Take your time and make sure to fill the area completely. Leave a little excess cement piled on top.
- 5). Run the edge of the trowel over the top of the patch to level off the wet cement. Wait a few minutes until the surface of the cement no longer looks slick and wet, then use the trowel to blend the edges of the new concrete into the old concrete to make the patch as seamless as possible. While the patched area will be ultimately disguised by floor tiles, tiles will lay better on a floor without raised ridges or bumps.
- 6). Wait at least three to four days before tiling the floor to give the cement time to fully harden. Cooler weather will prolong the drying time.
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