How to Restore a Marble Mantel
Marble mantels are one of the most beautiful features of historical Brooklyn brownstones, but too often they have faced years of serious neglect and poor paint choices. When we purchased the Slope Townhouse, all of the mantels were covered in several layers of paint — often in a green, brown, orange, green, brown pattern (apparently the previous owners were pretty indecisive). We knew that restoring the mantels to their original state was going to be one of the first projects we wanted to tackle, so we immersed ourselves in online forums and YouTube videos. After a lot of research and some trial and error, we found a process that worked to bring back the beauty of our white marble mantles. Read on for our tips + tricks.
To restore your marble mantel, you’ll need the following tools:
Paint remover — such as Jasco.
Synthetic paintbrush - a cheap one, to apply to paint remover.
Paint scraper — a plastic one, to protect from nicking the marble.
Blue painter’s tape — to prevent from getting any paint remover on your floors + walls.
Plastic gloves, paper face mask, and safety goggles — if you’re using a paint remover.
Sandpaper — light gauge, to sand off any last bits of stuck-on paint.
Baking soda — to lift stains from the marble.
Wooden paint stick — to stir the baking soda mixture.
Plastic container — to mix the baking soda with water.
Plastic wrap — to cover the baking soda mixture overnight.
Paper towels + garbage bags — for clean up.
Music or podcasts — because you’re going to be here for a while.
If your marble mantel is covered in layers of old paint, the first thing you want to do is strip this paint off using a gentle paint remover (if your mantel is only discolored, but not painted, skip ahead to Step Four). To do this, begin by taping off all of the seams where the marble meets the wall, and placing a drop cloth on the floor. (Admittedly, I have little patience for prepping, but this step is necessary to prevent any damage to the walls or floors surrounding the mantel.) Using a cheap synthetic paintbrush, liberally apply the paint remover over the entire marble mantel, cover with plastic wrap, and leave the remover to sit overnight. Leaving the paint remover on overnight will allow for a much easier removal process, but you can also work in small sections and leave the remover on for 30-60 minutes. Keep in mind: any time you are working with the paint remover you will want to wear gloves, a paper face mask, and safety goggles.
Once the paint remover has been on for your chosen period of time, remove a section of the plastic wrap and gently scrape back the lifted paint using a plastic paint scraper. You might be tempted to use a metal scraper, but this can very easily gouge or scratch the underlying marble. As you work your way around the mantel, try and scrape as many bits as you can from the indents and curves of the marble, but don’t go too crazy if you can’t lift out all of the paint (we will use sandpaper to buff some of this away later). If you find the paint is not coming off easily, reapply more paint remover, cover with plastic wrap, and leave the remover to sit for a longer period of time.
After the majority of the old paint is stripped using the paint remover and plastic scraper method, step back and assess the mantel. It’s at this time that you’ll see which areas need a bit more work (repeat Step Two), and which areas could do with a bit of light sanding using a fine gauge sandpaper. It is not important to get off every bit of paint — some of it will always remain, and from a foot or two away, it won’t ever be noticeable. Just make sure you take your time as you get closer to the original marble to ensure you won’t scratch or knick the stone.
If you’re happy with your mantel after Step Three, and your marble looks pretty white, you can skip Steps Four and Five. If instead you find that your marble looks a bit yellow — either from paint staining, cigarette smoke, or other mysterious causes — you will want to lift the color using the baking soda technique. To do this, mix baking soda with water in a large plastic container until you get a thick paste consistency (you will have to continually stir the mixture as you work). Using your hands, pack the baking soda paste onto the marble mantle, then cover the mantle with plastic wrap and leave to sit overnight. Warning: packing on the baking soda paste is a laborious and messy part of the project, so be sure you have a really great podcast or playlist lined up to listen to while you complete this step!
The following day, check that the baking soda has hardened (it should be a darker color as it’s pulled out a lot of the staining) and remove the plastic wrap. The baking soda paste will come off pretty easily, but I suggest again using your plastic scraper and having a large trash bag nearby to discard the hardened paste. To finish, wet a wad of paper towels or a large sponge, and wipe off any remaining baking soda residue from the marble. You should see a dramatic improvement in just one application, but if you so desire, repeat the process for an even whiter marble.