How to Repair a Damaged Concrete Floor

Learn how to repair damaged concrete floors with this step-by-step guide. Find out what materials you need and how to apply them for best results.

How to Repair a Damaged Concrete Floor

Concrete is a strong and durable building material, but it can still be damaged by temperature changes, heavy weights, and fallen objects. Fortunately, repairing a damaged concrete floor is an easy task. Start by chiseling and cleaning the cracked area so that the mortar adheres better. Next, mix the repair mortar and put it in the hole.

Straighten it and let it heal for 24 hours to complete the job. In addition to filling the crack with mortar, you can also use resin injection to repair concrete that is cracked or delaminated. Epoxy resins are used to structurally rejoin cracks that are latent and relatively dry, while various polyurethanes and some methacrylic acrylates are used to seal cracks or joints that leak water. It is usually not possible to structurally rejoin cracks that leak water, are dirty or are very wet. When making concrete crack repairs, you should always use an epoxy, polyurethane or polyurea crack repair product that can be sanded. They will cure and harden to a greater force than concrete.

Filling and bonding the tile with a high-strength epoxy is a great way to seal the crack. Mix a hard batch of resurfacing, using enough water to get a workable consistency. Scrape off excess so that repairs are aligned with the surrounding floor. Then sweep and remove any large pieces of concrete and vacuum the area to remove dust and small debris. The methods harden and bond the surface, trapping lime inside the structure, thus preventing further crumbling and delamination of the concrete floor. A stamped concrete treatment is similar to a microtopping, but contains more sand and provides a rougher concrete surface finish. Holes 1 inch or deeper require a mix of concrete with coarse crushed stone aggregate, which adheres well to existing concrete.

Chisel away any loose fragments along cracks or craters; no need to remove firmly adhered concrete. In commercial projects, depending on how the concrete slabs were built, cracks may occur due to lack of steel, poor concrete mixing, insufficient thickness, slump, hydrostatic pressure or soil movement. By installing carbon fiber concrete reinforcement products strong enough to withstand everything from bridges to basement slabs, you control cracks in the slabs and prevent them from failing or reopening. Self-leveling treatments can be applied to most concrete floors and are thick enough to help correct uneven surfaces and relatively deep surface damage. These methods can be used on interior and exterior surfaces and are intended solely for surface restoration; they are not suitable for repairing significant cracks or other structural problems in existing concrete slabs.