Repair exposed aggregate concrete - this is how you can do it

Exposed aggregate concrete can often be found as a classic floor and wall covering. Many plates are from the 1960s and 1970s, so damage cannot be ruled out. In most cases, these are cracks that have a negative effect on the structure of the panels.

Materials and tools for repair

Cracks in exposed aggregate concrete are caused by intensive use, weather conditions and errors in processing. They are clearly visible and must be repaired so that the stones do not loosen or the concrete continues to tear. In addition to the actual utensils, a filling material is required so that the renovation runs smoothly:

  • Epoxy resin mortar for outdoor use
  • hammer
  • vacuum cleaner
  • Trowel
  • Smoothing trowel
  • Screed or concrete sand (if mortar (€ 7.79 at Amazon *) does not contain sand)
  • Stones in the size and shape of the aggregate concrete
  • Protective gloves, a respirator and protective goggles


Start by cleaning up the cracks and removing any loose parts. To do this, first break off loose pieces with a hammer. The crack should then be as even as possible so that the mortar can be used easily and the granulate can be poured in. To do this, the crack needs to be widened a little. If you have succeeded, simply vacuum up the remains until the cracks are clean.

Repair exposed aggregate concrete: instructions

1. Mix the mortar

Epoxy resin mortar is already mixed and can be used immediately. Wear protective clothing as epoxy resins emit toxic fumes in their liquid state.

2. Apply mortar

The cracks are now completely filled with mortar with the mason's trowel. To do this, take a little of the mixture from the mixing vessel onto the trowel and distribute it in the crack. Make sure to press the mass into the crack so that it is incorporated well.

3. Fill in granules

Then distribute granules in the cracks. Just like the mortar, the stones are pressed into the crack. This will fill the crack, which will improve the structure. For this reason, you shouldn't skimp on granules.

4th. Sands

Now put sand on the mortar and smooth everything with the trowel. Remove excess mortar.

5. let dry

The mortar must dry for at least 72 hours before the exposed aggregate concrete can be walked on again. After 24 hours it is firm, but not resilient.