How to Join Concrete Slabs That Are Uneven

When moisture gets beneath the concrete slabs of a driveway, sidewalk or patio, sinking and/or lifting can occur. Excess water can cause the soil beneath the concrete to settle unevenly if the dirt wasn't compacted sufficiently to begin with. And if the water freezes it will expand, pushing some of the slabs or parts of the slabs up. Not only is the resulting irregular surface unattractive, the uneven surface can cause a hazard for foot traffic, too. There's no need, though, to contemplate tearing out your concrete and replacing it. You can inexpensively even out the surface yourself.

Surface grinder with a diamond wheel, available at a hardware store or rental shop
Power washer
Polymer based concrete patch, available at home improvement stores
Bucket
Hand trowel

Instructions

- 1
  Grind the surface of the concrete with the surface grinder, concentrating on the edge of the slab that is protruding above the rest of the surface. Grind this edge down so that is as level as you can get it with the surface of the lower slab.
- 2
  Power wash the surface of the concrete to clean away debris and dust.
- 3
  Mix the concrete patch with water in the bucket. Follow the manufacturer's instructions on the packaging.
- 4
  Pour some of the concrete patch over the surface in the area that you are evening out. Use the hand trowel to even the patch out as well as build it up, tapering it to meet the higher edge.
- 5
  Allow the surface to set for a few hours once you have it evened out satisfactorily.
- 6
  Pour some more of the patch preparation over the dried concrete patch on the joined area, and use the hand trowel to smooth the entire surface, making it as imperceptible as possible.

How to cure concrete pad

Thin Pour Concrete Recipes

Walkways