How to Fix Cracks in Cultured Stone

Daisy Cuinn

Cultured stone products such as cultured marble or granite tubs, sinks, and walls are a less expensive alternative to natural marble. The cultured version is made of stone dust and has an appearance similar to solid marble. Though small scuffs are easy to repair, cracks pose more of a challenge. Look for a specialized repair kit that lists cultured stone or marble on the label. More difficult than filling the crack is matching the finish with your existing cultured stone so the repair is invisible; kits come with finishing paint that you can tint to make an exact match.

Don't let a crack ruin your cultured stone bathroom.
  1. Clean the area around the crack thoroughly with a sponge or scrub brush and tub and tile cleaner. Rinse and let it dry completely.

  2. Sand the edges of the crack with a medium-grit sandpaper.

  3. Mix the filler with hardener as directed by the manufacturer until it's smooth. Apply the mixed filler to the crack, and scrape the surface flat with a putty knife. Allow the filler to dry for 10 minutes.

  4. Sand the slightly wet filler with a medium grain sandpaper. Switch to a finer grain sandpaper and sand the surface again. Repeat switching to finer grain sandpapers three or four times until the stone has been sanded with the finest 1,000 grit sandpaper, leaving the filled crack smooth.

  5. Allow the filler to dry overnight, or use a hair dryer to speed dry it.

  6. Dab a small amount of paint, included in the surface repair kit, to the dry filler. If the color is off, gradually mix in the included pigment as directed by the manufacturer until it matches.

  7. Pour the mixed paint into the included spray bottle and spray an even coat of paint over the filler. After 24 hours, buff the area to a shine and remove excess paint.