Repairing holes and cracks in cement/concrete floors

You can easily repair concrete with epoxy yourself. Concrete floors can be damaged, which can make it difficult to apply an epoxy coating or cast floor or will not produce the desired effect. Consider, for example, pits, holes and cracks in the concrete floor or (shrinkage) cracks in a cement screed floor. (Floating) anhydrite floors can also sometimes be cracked, making repairs necessary before a floor can be installed. In this article you can read how you can easily repair holes and cracks in your cement or concrete floor with epoxy and Stewathix.

Repair pits, holes and cracks in concrete and anhydrite floors

Depending on the extent of the damage, you will need different products. For large cracks you will need 2-component epoxy mortar for the concrete repair.  

Concrete repair of small cracks with epoxy:

• Epoxy primer for dry surfaces (this can also be used to make the filling paste)
• Stewathix
• Scales
• Mixing spatulas
• Mixing cups

Concrete repair of large/many cracks with epoxy:

• Small amount of epoxy primer for dry surfaces
• Epoxy repair mortar
• Buckets
• Spiral mixer

Step 1. Applying an epoxy primer for concrete

To repair defects in concrete with epoxy, you must first apply an epoxy primer (for dry surfaces). This improves adhesion and ensures that the repair can be carried out properly. Mix a small amount of epoxy with hardener on a scale and apply it to the crack, hole or damage. Allow the primer to cure for a minimum of 10 hours and complete the entire repair within 48 hours of applying the primer.

Step 2. Filling the crack with an epoxy paste

Mix another amount of epoxy with hardener and mix in a filler. Stewathix can be used for small cracks and damage (up to approx. 10-15 cm). This produces a smooth paste that can be used to patch holes, fill cracks (using a putty knife) and fill damage or holes. For larger concrete repairs you need two components. Larger holes can be filled with a mixture of epoxy and dry sand. A repair mortar can be mixed with this.

Step 3. Smooth the floor

After applying the epoxy paste or repair mortar, smooth the floor neatly. Large holes can be filled in 2 times if it is not possible to smooth them out in 1 time. If a leveling mortar is applied later, it is not necessary for the surface to be perfectly flat. If only one coating is applied, pay more attention to the smooth and smooth finish. If necessary, sand again with coarse sandpaper (40 or 60 grit) after curing.

Filling shrinkage cracks in a cement screed

Supplies:

• Epoxy primer for dry or damp surfaces.
• Floor squeegee
• Spiral mixer
• Mixing cups
• Mixing spatulas
• Scales

Cement screeds can sometimes show shrinkage cracks. These cracks can be recognized by their size (they are very narrow) and they are often present over the entire surface of the floor. These cracks can often be visible even after applying a primer and coating, so if the floor needs to be completely flat and of high quality, it is important to address these cracks in advance.

Step 1. Mixing the resin

For small quantities, mix the epoxy concrete primer and hardener with a mixing cup on a scale. For larger repairs, you can mix the entire package by adding the hardener to the primer and mixing with a metal mixer. Please note that the processing time is limited when creating large quantities.

Step 2. Filling cracks

Pour the epoxy mixture over the floor. Spread the primer with a floor mop and then leave for 10 minutes. The cracks then slowly absorb the epoxy and often become visible again after 10 minutes. Spread epoxy again with the floor squeegee and let it sit for a while. The idea is to spread as much epoxy into the cracks as possible. Then let it harden for at least 20 hours. Make sure you continue within 48 hours for optimal (chemical) adhesion.

After curing, you can apply another layer of primer. You can also divide this layer twice with the eraser. If all goes well, the cracks are now filled and a floor coating can be applied.

Help with concrete repair with epoxy?

With these tips you can get started yourself! Do you still have questions about concrete repair with epoxy? Please feel free to contact us. Our team is happy to advise you.