Using Epoxy to Repair Concrete Cracks

There is no doubt that concrete is strong and durable. However, if not correctly installed, it can still get cracks and damages. Cracks in your concrete don't only cause an eyesore, but it can also take from the overall value of your home. Concrete repairs are easy that is why we recommend you giving it a try. If you are looking for a DIY material to help you with the repair, the most recommended product to use is Epoxy. It is a 2-component polyurethane polymer that doesn't need routing. Epoxy is ideal for filling hairline cracks, can be applied in freezing temperatures, and is stronger than concrete; that is why it is best to use for repair. However, you have to remember that repairs can only be a temporary solution, depending on the root cause of the problem.

Common Reasons for Cracked Concrete
Sub-base Issue- A crack can be the result of concrete that wasn't appropriately compacted. Concrete will accumulate in one area instead of spreading evenly across the entire concrete. The concrete will eventually try to even itself out which will lead to cracks.

Cold Temperatures- The cold weather brought by the winter season can be concrete's worst enemy. When the dirt accumulated under concrete freezes, it can lift the concrete and expand. The pressure coming from the expansion can then lead to cracks.

Shrinking- It is natural for concrete to shrink when it dries. However, when the mixture was not cured correctly, or there was too much water, concrete will crack when it shrinks. One way to prevent concrete from cracking when it dries is by cutting expansion joints into the floor.

Whatever the reason for the cracks in your concrete, repairing it can be a band-aid solution. If there is an issue with the sub-base, there may be a need to remove and redo it. If you repair the crack, it may solve the problem for a few months, but the problem will resurface after some time. A crack that is caused by the cold, you may not need to think about it until the next winter. If the problem is due to shrinkage, there may be a need for a permanent repair.

How to Repair the Crack

1. You should first key the crack with a hammer and a chisel. This process is done to ensure a more effective repair. You have to cut under the edges of the crack to make a large opening at the bottom.  Tip: You can use a file to enlarge the crack and make a more effective repair.
2. Using a wire brush, clean the crack of any debris that may have entered the crack. You can use a vacuum for a much thorough cleaning.
3. Using water, clear all remaining debris in the area. If there is a presence of oil or grease, you can use a strong cleaner to ensure the area is clean before you begin the repair.
4. Once the area is clean, fill the crack with concrete repair resin.
5. Put the dry silica in the crack.
6. Add more resin to the sand to fill the crack up to the surface.
7. Wait for it to dry. It usually takes 10 to 15 minutes for it to dry up completely. Once dry, scrape the area with a putty knife to smooth the surface.
8. The repair may still look rough after so you can still sand the surface for a clearer and smoother finish.

Once you're done with the process and you are still not satisfied with the result, you may want to consider hiring a professional concrete contractor to handle the job for you.  

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