How to Refill Gaps in Concrete Tiles on Steps

Sweep the steps to remove any sand, dirt or other debris that is on them. Plug in a vacuum approved for outdoor use and attach a crevice tool to the end of the hose. Turn the vacuum on and move the crevice tool over the gap in the steps to suck out any debris that has fallen into it.

Fill a bucket with 1 gallon of water and 1 to 2 tablespoons of a degreasing cleaner. Put on rubber gloves and insert a stiff-bristled brush into the mixture. Scrub the surface of the gap to remove any dirt or grease that will interfere with the repair process. Rinse the area with clean water and allow it to dry overnight.

Open a tube of concrete sealer resin. Hold the resin tube over the crack and squeeze in the amount instructed. Some concrete resin comes in a dual-tube container that fits into a caulk gun.

Pick up a handful of 30- to 40-grit silica sand and drop it into the crack until it reaches the top of the gap. Brush away any excess sand from the top of the step immediately.

Squeeze additional resin material onto the top of the sand in the gap until it is completely wet and begins to pool up slightly.

Allow the repair to sit undisturbed for at least 10 to 15 minutes. Then place the flat edge of a putty knife over the area and pull it straight over it to scrape off any excess resin and sand.