How to Repair Holes in Concrete Floors

Learn how to repair holes in your home's concrete floors using quality mortar mix with crushed stone aggregate for deeper holes. Find out what products work best for crack repair.

How to Repair Holes in Concrete Floors

If your home has concrete, you may notice holes forming due to harsh weather or rodents. Most of these can be fixed with a quality mortar mix, although you should use one with a crushed stone aggregate to fill holes over 1 inch (2.5 cm) deep. It is important to treat holes as soon as you find them to prevent water and rodents from further damaging the concrete and entering your home. Before attempting to fill a hole, it is essential to clean up any loose concrete and other debris.

Then mix the mortar, fill the hole and level it to blend into the surrounding structure. Concrete takes time to cure, so keep the patch moist for several days for a stronger hold.

Patching concrete holes

is a simple weekend project and can help protect your home for decades. For cracks or filling cracks, it is best to use a compound based on epoxy, polyurethane or polyurea that can be sanded.

These cure and harden to a higher strength than concrete and will also prevent water intrusion. You can grind them or sand them flush with the concrete and they will accept paint or an epoxy coating. They usually consist of a 100% solid epoxy gel that has an aggregate of sand that can be mixed as a filler. Once you apply it to the crack, it can be smoothed with a trowel with a concrete float.

One of our favorites that we've recently reviewed is Xtreme Set 100 from Legacy Industrial. A small area that is only 1″ deep doesn't need the 30 days. The reason why concrete is being dusted is because too much water was used on the surface or even in the mixture. A common mistake people make is adding a little water when applying the palette to make it look smooth. This weakens the surface layer, and small fines in the concrete rise to the surface.

This surface is a weak layer and will continue to dust and deteriorate until the coating no longer adheres to the joint. Epoxy, polyurethane and polyurea crack repair products, on the other hand, form a tenacious bond with properly prepared concrete and do not need an inverted cut to stay in place. Also do not use a self-leveling sealant, as they are primarily designed for sealing control joints in concrete. However, if you are applying a colored paint or a colored epoxy sealant, it should have the appearance of a concrete slab that is well smooth and free of blemishes. Simply pouring wet concrete into a hole in the doorway, sidewalk or basement floor will not allow for a lasting repair. However, in addition to shrink joints working, you can still get cracks in other parts of the concrete due to sedimentation of the earth under the slab, curing problems, or other variables beyond your control. If you can't find a ready-mixed concrete patch, you can make your own by mixing one part cement with 2.5 parts of fine sand.

Chisel the bottom of the hole until it is flat and enlarge it slightly so that the bottom of the hole is wider than the top. Once the area is clean, mix the repair mortar and water in a bucket and use a trowel to dig it into the crack or hole. Then sweep and remove any large pieces of concrete and vacuum the area to remove dust and small debris. Temperature changes, heavy weights and fallen objects can damage the concrete floor by causing cracks and holes. So, if you coat the joint, what will happen is that the concrete under it will crack through the coating, or worse, it will come out and take the coating with it. Use a hammer and cold chisel to level the bottom of the hole and slightly cut its sides so that the patch does not come loose. Holes 1 inch or deeper require a mix of concrete with coarse crushed stone aggregate which adheres well to existing concrete.

Another excellent crack repair product that we have experience with is PC Concrete Epoxy Crack Repair on Amazon.

Riley Ryan
Riley Ryan

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