Everything you need to know about sealing marble & natural stone
Sealing natural stone is vital to maintain its appearance, prevent stains, & make cleaning a breeze. Here's how to do it! It's easy. We promise.
How to Seal Natural Stone
A common misconception is that you need to hire a professional to reseal your stone. While you certainly can pay someone else to do it for you, we recommend that you keep your cash & do it yourself. It is not difficult, & it only adds about 30-45 minutes to your usual cleaning routine. Here's how we do it:
Clean the surfaces to be sealed. Before sealing your stone, it is imperative that you clean it. Otherwise, you'll be locking in any dirt that was on it. For our stone cleaning tips, click here!
Thoroughly dry the area. Wipe it with a soft cloth, place a fan in the area, or simply wait a while. Make sure you let the area dry of any & all moisture so that the sealer is able to fully penetrate your stone.
Mask off the areas that you don't intend to seal. Sealer can't penetrate nonporous surfaces (like tubs or porcelain tiles), and it may leave a residue on painted surfaces like baseboards & cabinets. Save yourself a bit of clean up time by masking these off beforehand.
Read all of the directions on the sealer that you plan to use. Although some of these steps are universal, we have tailored our steps to align with the instructions for Stonetech's BulletProof Sealer. If you're using a different brand, follow their directions instead.
Shake it, baby! Shake well before use.
Liberally apply an even coat of sealer. Use a paint brush, paint roller, or low-pressure sprayer depending on the size of the surface you're covering.
Alexa, set a timer for 15 minutes. Allow the sealer to penetrate the surface for 10-15 minutes. Note: It is imperative that you do not allow the sealer to dry during this step, so do not use this time to take a break! Instead, keep a watchful eye on the area & apply more sealer as needed to keep the entire area wet for the duration of this time.
Dry surface with clean, absorbent towels. Wipe off the excess sealer thoroughly so as not to leave any residue behind.
Assess the situation. If you're planning to apply a second coat, the optimal time to do so is within 30-40 minutes of the first. So now is the time to either repeat steps 6-8 or move on to step 10.
Make sure you didn't leave behind any sealer residue. Look for a cloudy, white film on the surface of your material. If you see any, the best way to remove it is to reactivate it by applying a bit more sealer to the area. Then gently scrub it away with a soft-bristled brush or sponge.
Don't use freshly sealed surfaces for six to eight hours. Once you finish your application, keep family members, pets, & yourself out of the area while it cures. Sealer takes 24-72 hours to fully cure, but you can resume normal use after just 6-8 hours.
Put a reminder in your phone or planner to reseal your surfaces again next year. Although many sealers boast that they last five, ten, or fifteen years, you'll get the best results by resealing annually. Or better yet, reseal as needed. Our easy test for determining whether or not it's time to reseal is below.
Enjoy the peace of mind that comes with knowing your surfaces are protected. When it comes to natural stone maintenance, the best offense is a good defense. You can't always prevent muddy puppy paws, a toppled glass of red wine, or coffee rings from your morning latte, but you can rest assured knowing they're no match for a fresh coat of sealer.
How can I tell if my stone has been sealed?
Sealer repels water, so you can tell whether or not your stone has been sealed properly by flicking a few drops of water on it. If the water beads up tightly (like raindrops on a freshly waxed car), then you're in good shape! However, if the edges of the water droplets are spread out (or worse, start to soak into the stone), then it's time to reseal.
Always do this test in conspicuous areas for best results. Since sealer wears off with use, the areas that get the most wear will need to be resealed sooner than out-of-the-way places. The floor right in front of your vanity, for example, will need to be resealed much sooner than the floor of a linen closet.
Why does natural stone need to be sealed?
Natural stone, including marble, travertine, & limestone, must be sealed when it is installed, ideally before it is grouted. It should also be resealed annually or as needed to protect it from stains, etching, & other signs of wear.
Unlike porcelain, which is virtually impermeable, natural stone is full of microscopic pits & holes, called pores. Its porosity is what makes natural stone venerable to staining & discoloration. Sealer protects stone (and other porous materials) by repelling oil- and water-based liquids, thus preventing things like makeup, spaghetti sauce, and olive oil from soaking in & setting as a stain.
While there are special cleaners and poultices that can be used to remove stains from natural stone, it is much easier to prevent them than it is to remove them. It is also much easier to clean sealed stone, because spills stay on or near the surface rather than immediately absorbing.
It is also important to note that sealer does not make stone completely impervious to staining, and while it does repel liquids, it is not intended to make your material waterproof. So even if your stone is well sealed, spills should still be cleaned as promptly as possible to minimize potential damage.
What kind of sealer should I use?
Stonetech's BulletProof Sealer is our favorite everyday sealer. It is a professional grade penetrating sealer that preserves & protects porous natural stone (including marble, travertine, slate, limestone, & granite) as well as porous tile, masonry, & grout. It cures to a natural look, meaning it won't alter the color or finish of your material in any way. This makes it our go-to for everyday applications.
Stonetech also offers Enhancer Pro Sealer, which enhances the color of natural stone in addition to protecting it. Although it can be used to deepen colors on any natural stone or porous material, we most often use it on pebble mosaics, multicolored slates, and travertine blends, where it brings out shades of green, burgundy, gold, and black in stone that may appear muted or neutral otherwise. To see what your material would look like with an enhancing sealer, simply wet an unsealed piece with clean water.
What else I should be sealing?
Although sealer is most commonly associated with natural stone, there are many other products that benefit from a layer of sealer.
Ceramics with crackled glazes should always be sealed before they are grouted to prevent grout from sticking in the cracks of the finish. Otherwise, you will end up with a hair-like pattern of grout on the surface of your tile that is extremely difficult to remove.
Encaustic cement tiles are extremely porous, so much so that they can absorb the color pigment from the grout if they aren't sealed beforehand. These have to be sealed thoroughly before they are installed and again before they are grouted, and even then, we always recommend that you use a light or blending grout color to minimize the visibility of color transfer that may occur along the grout lines.
Terrazzo is a mixture of cement & marble, both of which need to be sealed. So naturally, it needs to be sealed as well.
Unglazed ceramics, Saltillo & terracotta tiles, and brick veneers are notoriously difficult to clean due to their high porosity & rough matte textures. Sealing them makes cleaning much easier in addition to safeguarding against staining because your spills will sit closer to the surface rather than immediately penetrating the dry material.
Grout is very porous and can be sealed if desired to prevent staining. Most of the grouts that we recommend are pre-sealed right out of the bag, but resealing every year or so helps to keep your white & light colored grouts looking like new. However, because sealer still allows water to pass through, improperly waterproofed showers will not be remedied by sealer. Nor will sealer clean or whiten already-stained grout.
Materials that are not porous, like glass, porcelain, & glazed ceramics, never need to be sealed. In fact, they will not absorb sealer at all, so there is no benefit whatsoever of attempting to seal them. That being said, even if your tile is imporous, it's not a bad idea to seal your grout now & then if you want to keep it looking bright & clean.
We hope you found this article helpful. If you still have unanswered questions, please drop them in the comments below!