Natural stone countertops have become very popular due to the variety of patterns, textures, and colors that satisfy a broad range of personal tastes.
- Granite countertops can be the most durable of all natural stone countertops.
- However, one drawback to the use of stone countertops (and cast concrete counters, too) is the ability of the porous natural material to absorb water, food particles, and bacteria.
- Thus sealing the countertops is a good idea.
In general, I recommend having countertops sealed at the factory and then applying a second coat after installation to cover any edges that were cut or trimmed. For kitchen and bath countertops, I'd recommend a water-based sealant such as AFM Safecoat MexeSeal or StoneTech Impregnator Pro Sealer.
Before you buy the product, read the manufacturer's Material Safety Data Sheet (MSDS) and installation instructions. (You can ask the retailer or manufacturer for the MSDS, or you may be able to find it online.) For best indoor air quality you're ultimately looking for a zero-VOC product. Finally, keep in mind that some sealers can change the finish, gloss, or color of the material, so you should do a test sample before sealing the entire countertop.
Another thing to consider when installing new stone countertops is the adhesive that is used to secure the stone to its substrate. Traditional adhesives are often epoxy-based and extremely high in VOCs. I'd recommend that the adhesive be specified as zero-VOC and the substrate be specified as formaldehyde-free plywood.
These are critical components of the overall countertop assembly that are often overlooked. If you choose the wrong materials, they will offgas toxic compounds into your home's air for a long time.
For more information:
See GreenHomeGuide's Stone & Tile Know-How section to learn more about selecting natural stone products for your home.
See GreenHomeGuide's Paints & Coatings Know-How section for more advice on choosing the right finishes and sealants for your projects.