How to Make Concrete Stain Look Marbleized

Layered application of diluted acid stain will help create a marbleized effect.

Particularly on older concrete slabs exposed to the elements, the variable porosity of the slab allows the stain to penetrate to different depths, creating natural areas of light and dark staining. If you want to try an additional marbleizing effect, layering diluted acid stains will give additional depth to the stained concrete.

1. Remove any sealants with a chemical stripper or a floor grinder equipped with a 60-grit stone. The concrete must be exposed in order to accept the concrete stain.

2. Power wash the concrete slab to be stained to remove all dirt and debris. If the concrete slab is inside, use a wet vac.

3. Create a 50 percent acid stain solution by mixing one-half acid stain and one-half water in a 2 gallon plastic bucket rated for acid. Pour the acid stain into the water to avoid a violent chemical reaction.

4. Brush the stain on the slab with a wide foam brush. Work in multiple directions.

5. Mist any apparent brush lines with water from a spray bottle. This will blur the lines but not remove them. The brush lines will add dimension to the marble effect.

6. Allow the stain to dry for the manufacturer’s recommended amount of time.

7. Mix a 75 percent acid stain solution by mixing three-quarters acid stain with one-quarter water. Pour the acid stain into the water to avoid a violent chemical reaction.

8. Brush on the new solution in wet, uneven stokes in a 2-foot-by-2-foot square.

9. Blot the stain with wadded up plastic wrap or a plastic shopping bag. Continue blotting with the crumpled plastic until you have created a 4-foot-by-4-foot square.

10. Mist the area with water from a spray bottle to blur the lines. If you are satisfied with the intensity of the lines, this step is optional.

11. Repeat Steps 8 through 10 on a fresh section of concrete. The acid stain will destroy the plastic wrap or shopping bag as you work, so you will have to replace it frequently.

12. Allow the stain to dry for the manufacturer’s recommended amount of time.

13. Use the full strength acid stain sparingly to create areas of dark contrast. You can paint on thin lines of veining with a foam brush or use the blotting technique described in Steps 8 through 10 with thin layers of stain.