Tile Areas:
Sealing tile grout gives your tile surface greater water and mildew resistance, and helps prevent grout from getting dirty or stained. Unsealed grout will absorb dirt, grease and grime such that it becomes very difficult to clean. Your countertops, backsplashes, bathroom floors and master bathroom shower have glazed ceramic tiles, so you only need seal the grout itself.
Types of Sealer:
Non-pigmented penetrating sealers don't produce a gloss on the surface, but can slightly darken the grout's natural color. Use a good quality penetrating sealer for baths or showers. After the sealer dries, the grout looks normal until water comes into contact with it, and then the water will actually "bead up", as if your grout had wax on it. We recommend you use latex water-based grout sealer. It's ok if you get some sealer on the tile surface providing the tile is glazed, but be sure you wipe off the excess before it dries, or it will be there permanently. It dries fairly quickly, forming a haze on the tile that is nearly impossible to remove. You may also use acrylic sealer but it is more difficult to use as you need to specifically apply it just to the grout.
Sealing Slate:
For porous materials such as the slate around your fireplace you should seal the actual surface of the slate in order to prevent staining. The same product can be used to seal the grout and slate surface.
When to Reseal:
You should reseal your countertops, soaker tub surround and shower about every six months. Backsplashes, bathroom floors and fireplace slate should be resealed about once a year or as needed. You can determine if areas need resealing by dipping a small amount of water on the grout itself. The water should bead up, if it does not, then it is time to reapply the sealer to the area.
Epoxy Sealer:
If you have upgraded to epoxy based grouts in a portion or in your entire home, sealing that grout is not necessary.
Other Tips:
• Do not mix brands and types of sealer; stick to the original sealant for re-application.
• Try not to use any ammonia-based cleaners on the tile since it will strip off the sealer.
• Always strictly follow manufacturer's instructions for the product's use so that you will get its full intended benefit.