It is generally a good idea to use a penetrating sealer to seal your stone, tile, and masonry. This is especially true in high traffic areas and areas subject to a lot of use, like bathrooms and kitchens. A sealer will help to protect against stains, make regular cleanings easier, and extend the life of the stone or other material. In exterior applications, a good sealer will help to protect against the elements and prolong the life of the material. In particular, solvent-based sealers tend to provide superior protection in exterior applications.
Q: What are penetrating and impregnating sealers?
Penetrating and impregnating sealers (a type of penetrating sealers that penetrates particularly deep) use either a water carrier or a solvent-based carrier to deliver polymers into the pores of material. When the carrier evaporates, the polymers are left behind to react with the material and form a barrier that will protect against stains.
Penetrating sealers will protect against water stains. Some penetrating sealers, however, will be able to protect against both water and oil stains. They will not protect against physical damage on the surface such as acid etching or scratches. Most will not alter the appearance of the material, but some do contain a color enhancing agent that will darken and enhance the natural colors in the material.
A topical sealer, or surface coating, is a type of sealer that sits on the surface of the material, providing a barrier against stains, protecting against damage caused from scratches and abrasions, and often altering the appearance of the material. These surface coatings often require more maintenance than penetrating sealers.
Q: I’m sealing a bathroom… what kind of sealer should I use?
When it comes to sealing bathrooms, there are a couple of things you should look for in a sealer. Obviously, bathrooms are exposed to a lot of water, but they are also exposed to oil, such as body oil and oil found in products around the bathroom like makeup. You’ll want to make sure the sealer has good protection against both water and oil.
Additionally, you want a sealer that is going to be breathable. Many topical sealers will not allow for good vapor transmission. If moisture gets underneath a topical sealer, mold and mildew and can develop under the sealer and in the material. Without stripping the sealer first, removing the mold and mildew will be very difficult. Some topical sealers can also become very slick when wet, which is dangerous combination in a bathroom.
A high-quality penetrating sealer that is breathable and provides protection against both water and oil stains is recommended for sealing stone, tile, and grout in showers and bathrooms.
Some topical sealers are designed especially for adding a glossy shine to the finish of the material. In addition, they will provide water and oil stain protection. These surface coatings should only be used on textured surfaces such as tumbled marble, flamed granite, slate, sandstone, terra cotta, cement pavers, and masonry surfaces. Also be aware that these types of coatings can become slippery when wet.
Q: What kind of sealer will give me a “wet look?”
There are two different kinds of “wet look.” A “wet look” that refers to a darkening of the colors (but not adding a shiny finish) can be achieved with an enhancing sealer. Some penetrating sealers will have an enhancing agent that will enrich and darken the natural colors.
A “wet look” that refers to a shiny or glossy surface can be accomplished with a topical sealer that is designed especially for achieving a glossy finish.
Q: I have a saltwater pool. What sealer should I use?
There are penetrating sealers designed to be used around saltwater pools. These sealers will provide protection against water and are much more resistant to damage from salt than typical penetrating sealers.
A water test can be performed. Spill several drops of water on your surface of the material. Allow the water to sit for about 10 minutes, then wipe off. If the stone has darkened, it needs to be resealed.
Q: Will using a penetrating sealer 100% protect my stone?
No, penetrating sealers will not provide 100% protection. These sealers are designed to give you more time to clean up spills so that staining doesn’t occur. Staining may still occur if a spill is left unattended for an extended amount of time. Additionally, because a penetrating sealer sits below the surface of the material, the surface is still subject to physical damage including acid etching and scratches.
Q: What are VOCs?
VOC stands for Volatile Organic Compounds. VOCs release vapors and fumes that are considered harmful to humans and the environment. They can be found in a range of products from paints to underarm deodorants. Some states have strict laws regarding the sale and transport of sealers that are considered high VOC. When using a sealer that is considered high VOC, it is important to take the appropriate safety precautions including using the sealer in a well ventilated area and using a proper respirator mask.
Q: Do I need to seal my grout?
Sanded and un-sanded grouts are both very porous, so yes, they should be sealed. When sealed with a good penetrating / impregnating sealer, the grout will be much more stain resistant and easier to clean. 100% epoxy grout will not need to be sealed.