Sealing and Protecting
Most natural stone is porous, which means liquids and other agents can get into those tiny holes and leave stains behind. Most stains can be removed, but to minimize the problem altogether, it's best to take precautions. There are different kinds of sealers. With most you will see no noticeable difference on the surface, others types of sealers called enhancing sealers will actually bring out the rich colors in some stone. We can help you determine which is the most suitable one for your needs.
FAQ's About Sealers
We get a lot of questions about sealing. There are a lot of misconceptions out there about what impregnating sealers are... and aren't. We have assembled our most frequently asked questions about sealers. If you don't see your answer here, don't hesitate to reach out to us.
Q? What does sealing or impregnating stone really mean?
A. In the stone industry, sealing and impregnating are often confused. The main objective of an impregnator is to protect the inside of natural stone from staining. Impregnators help prevent fluids from penetrating into the stone surface, but they do nothing to protect the top surface of the stone. They do not prevent traffic patterns, and they will not prevent etching from acid spills on marble. An impregnator will keep the acid out of the stone but not off the top surface.
Q? Does an impregnator sealer provide stain proof to the stone?
A. No. Most penetrating sealers are designed to be either water or oil resistant, not water or oil proof If a liquid is left on the stone long enough, it will eventually penetrate and stain. Penetrating sealers are designed to give you time to clean up the spill before staining occurs. Nor are they designed to prevent acid etching that happens from lemon, vinegar, tomato and other acidic foods and drinks. Any acid will etch the surface of most marble and limestone, whether scaled or unsealed.
Q? Does an impregnator sealer prevent oil penetration?
A. Most sealers will prevent water and oil penetration, but it is very difficult to stop hot cooking oil from penetrating into the stone, because it can melt the resin in the stone.
Q? How does impregnating sealer works?
A.Impregnators are a mixture of silicon, resins, and usually a mineral spirit, which is a solvent. That is why they have a strong odor. The mineral spirit is added to the mixture because it acts as a carrier for the silicones and resins. The mineral spirit rides the resin and silicone into the stone as a liquid form. The mineral spirit evaporates out of the stone and leaves the silicone resin. The silicone and resin then begin to cure into a solid form, thus forming a fluid repellent membrane in the pores of the stone. This all happens within five to 10 minutes. However, complete curing time is usually 12 hours due to moisture content in natural stone.
Q? Is it enough to maintain the stone just by applying impregnator?
A. No. Impregnators and sealers are preventive measures that provide extra protection to the stone. Natural stone still needs to be maintained with proper stone care products after it has been sealed. Sealers will last longer and work better when the stone is properly cared for.
Q? How often should an impregnating sealer be reapplied?
A. Impregnating sealers will not last forever. Over time, the sealer loses its strength and bonding to the stone and eventually evaporates away. In these terms, a stone sealer can be compared to car wax on an automobile, which eventually evaporated off the paint. The sealers lose their ability to protect, as they get older. Some sealers are better than others are, and some will last longer. However in high traffic areas (shower, kitchen or dining room floor), the sealer will not last more than a year.
Q? Why does the impregnating sealer quickly wear in a high traffic area?
A. In a high traffic floor area, the impregnator wears as the stone surface wears down. The reason is because impregnators only penetrate approximately 1/6 inch (1.6 mm) or less. Since stone vary in their porosity, the sealer will penetrate more in some stones than in others. Additionally, some sealers require one coat and others require two or three.
Q? How do I know if an impregnating sealer was applied sufficiently?
A. A good way to measure the strength of an impregnating sealer is to apply moisture to the surface and to see if the color underneath the water darkened within five minutes. If the stone darkens, these means that moisture has penetrated, and a fresh coat should be applied. It is important to remember that if the moisture does not bead up on the surface, it does not necessarily mean that the impregnator / sealer is not working. Beading usually occurs with a new application of sealers. As the sealer ages, the beading action is reduced.
Q? What is the purpose of impregnating / penetrating sealer?
A. Impregnator or penetrating sealers are designed to penetrate below the surface of the stone and either deposit solid particles in the pores of the stone, or coat the individual minerals below the surface. Penetrating sealers work by restricting water, oil and dirt from entering the stone or tile. Properly applied, a good impregnator sealer will not affect the texture or the appearance of the stone. For all polished and smooth surface, an impregnator is recommended since sealers, which are surface coats, will not bond and will be easy abraded.
Q? Why is it so important to protect natural stone?
A. To preserve the longevity of a natural stone installation it is very important to protect it with a proper sealer. All natural stone are porous (granite less than ½ % water). As long as we have an absorption factor, stone will stain and deteriorate over time since the regular tap water used in maintenance contains salts, minerals and chlorine -which are all detrimental to natural stone. In addition more and more “decorative” marbles are being selected and used for their beauty and not their strength. These marbles are generally very prone to foot abrasion and staining.