To seal a marble backsplash, clean it with a pH-neutral cleaner, let it dry completely, test a penetrating stone sealer on a hidden spot, apply it in small sections, let it soak in, wipe off the excess, and let it cure. Most backsplashes need resealing every 6 to 12 months.
Marble backsplashes are a timeless addition to any kitchen or bathroom, with natural veining no two slabs share. But marble is porous, so it absorbs liquids and stains if it isn't sealed. Sealing protects the stone and keeps it looking the way it did the day it went in. Here's how to do it.
What You'll Need
- Marble sealer. Choose a high-quality penetrating sealer made for natural stone. Avoid topical sealers that sit on the surface; they don't protect as well.
- Microfiber cloths. For cleaning and buffing without scratching the marble.
- Soft sponge or applicator pad. To spread the sealer evenly.
- pH-neutral cleaner. A mild cleaner to prepare the surface.
- Protective gloves. To protect your hands while you work.
- Painter's tape. Optional, but helpful for protecting counters and cabinets next to the backsplash.
How to Seal a Marble Backsplash, Step by Step
1. Clean the marble
Remove any dirt, grease or residue that could keep the sealer from soaking in. Use a pH-neutral cleaner and a microfiber cloth, and avoid harsh chemicals, acidic cleaners or abrasive pads that can damage marble. Then let the surface dry completely. Moisture keeps the sealer from penetrating the stone.
2. Test the sealer
Before you seal the whole backsplash, test the sealer on a small, hidden area to make sure it doesn't change the color or look of the stone. Apply a little, let it sit for 5 to 10 minutes, wipe off the excess, and check the spot.
3. Apply the sealer
Put on your gloves and tape off the surfaces next to the backsplash if you like. Pour a small amount of sealer onto the sponge or pad and work in small sections from top to bottom so it doesn't drip. Use a circular motion and overlap each section slightly. Be generous: the sealer has to soak into the stone.
4. Let it soak in
Leave the sealer on for the time the manufacturer recommends, usually 10 to 15 minutes. That's when it fills the pores and forms the protective barrier. Don't let it dry on the surface, or it can leave a hazy film.
5. Wipe off the excess
Use a clean, dry microfiber cloth to wipe away any sealer left on the surface. Buff in a circular motion so there are no streaks. This also brings out the natural shine of the marble.
6. Apply a second coat if needed
Depending on how porous your marble is and which sealer you use, you may need a second coat. Repeat the same steps, and let the first coat cure fully before you start.
7. Let the sealer cure
After the final coat, let the sealer cure, usually 24 to 48 hours. Keep the backsplash dry and don't lean anything against it while it cures.
Keeping Your Marble Looking Good
- Clean it regularly. Wipe the backsplash with a soft cloth and a pH-neutral cleaner. Acidic or abrasive cleaners wear down both the sealer and the marble.
- Reseal when it's time. Depending on the sealer and how much use the backsplash gets, plan to reseal every 6 to 12 months. To check, sprinkle a few drops of water on the marble. If the water soaks in instead of beading up, it's time to reseal.
Thinking About a New Backsplash?
Marble isn't the only option. Quartz looks like stone and never needs sealing. See quartz vs. granite for how different surfaces compare, or kitchen remodeling for how we plan backsplashes as part of a new kitchen.