How to Clean and Seal Natural Slate

Slate is made of thin pieces of stone.

Slate is a thin piece of stone sheeting used for anything from roofing material to flooring to countertops. If you plan to use slate for flooring or for countertops, you must first clean it and then seal it to ensure you protect it from the elements and abuse by heavy traffic. The process does not require professional intervention to complete. You must pay attention to the details, however, to ensure the sealant stays on the stone for an indefinite period.

Things You'll Need

• Alkaline stone cleaner
• Bristle brush
• Painter's tape
• Lamb's wool roller
• Sealer

Instructions

1. Clean the surface of the slate with an alkaline-based stone cleaner and a bristle brush. The cleaner will remove any dirt from the surface of the slate and the brush will break away small pieces of stone flake that otherwise would break off later and cause the sealer to peel off.

2. Dry the surface of the slate with a lint-free or microfiber towel. It can sometimes take several days for the stone to completely dry inside. Wait until all of the stone returns to its lighter natural shade. If you seal the slate with a high level of moisture trapped inside, the moisture will force the sealer to peel.

3. Tape off any areas around the slate that you do not want to get sealer on. For example, cabinet borders, wall borders and floor fixtures. Use painter's tape for this.

4. Apply one coat of sealer to the surface of the slate with a lamb's wood paint roller. A paint roller will give you a flatter finish than a paintbrush will give you. Allow adequate drying time per the instructions on the sealer. The first coat will likely soak into the porous stone.

5. Add a second and a third coat of sealer. Again, allow adequate drying time before coats.

6. Buff the sealer to a shine with a microfiber cloth.

References

• Integrity-Tile-and-Grout-Cleaning: Sealing Travertine