It's inevitable and normal that a concrete slab will eventually develop some cracks.
Luckily, it's an easy fix (and an important one to prevent further damage from water seeping in).
You'll need a few supplies before you get started:
Step-by-Step Instructions:
- Remove any movable debris in the crack. Use a crowbar for larger chunks and a broom/blower for the smaller stuff.
- If the crack is larger than 1 inch wide and 2 inches deep, you’ll need to use a backer rod. The idea is to take up some of the space so that the concrete mix will be able to set.
- Mix your concrete patching. Only mix what you can use in 15- 20 minutes. Follow the instructions on the package, and be sure not to mix too fast as it can cause air bubbles and will affect how well it seals.
- Use your putty knife to spread the mix into the crack. Make sure to use a fair amount of pressure to force the mix in all of the corners.
- Allow to dry at least 24 hours before any weight is applied.
Finally, for your viewing pleasure, here's a video of me repairing a concrete crack:
Good luck!
Brian