The Truth Behind “Factory-Sealed” Counter Tops

Many consumers often misinterpret the term widely used in the counter fabrication industry known as “factory sealed” and believe that their brand new counter top has actually been chemically sealed.

When a stone is mined in a quarry, it is typically rough in appearance. At this point, the stone is quite porous and easily absorbs moisture. In the fabrication of counter tops, the stone slab undergoes an intensive grinding and polishing process through the use of heavy-duty commercial machinery, diamond pads and heavy weights to make it smooth and uniform. This process of grinding and polishing, helps seal the pores of the stone making it less able to absorb moisture and therefore less prone to staining. This is what is referred to as “factory sealed” counter tops which is not to be mistaken with counter tops which have also been chemically sealed.

If a counter top fabricator reassures you that your stone purchase has been “factory sealed,” don’t be afraid to ask more questions, such as:

  1. Has the stone been chemically sealed as well?
  2. What type of sealer was used – penetrating or topical, water-based or acrylic-based?
  3. What is the name of the sealer to determine if they used a commercial professional sealer which lasts longer or an off-the-shelf sealer accessible to the everyday consumer which requires yearly re-applications?
  4. How often should you re-apply the sealer to protect your marble or granite counter top investment?

Any stone installation is better protected by going one step further by having a chemical sealant applied to the surface to create that impermeable barrier that will protect against organic stains.

Most often, we recommend a “professional” water-based commercial sealer that protects the surface, does not alter the finish or look and still allows the stone to breathe. However, different sealers may be recommended depending on the use, type of stone, and the desired outcome. Most sealant manufacturers require a minimum two-coat application, so the more informed you are, the better protected you will be.

MARBLEMaster has tested many commercial sealers on the market and is a certified sealant applicator. Our services include stain removal, technical assessments and reports, surface restoration, polishing and, of course, professional sealant application.