Natural stone sounds like a naturally healthful option, but even stone warrants a little caution. Consumers appreciate the look of stone counters—particularly granite and marble—but not the porosity that makes them prone to stain. Hence the popularity of engineered stone and solid surfaces that won’t blemish with wine-bottle rings, splashes of olive oil, and coffee spills. Fabricators will polish natural stone with resins and synthetic sealers to prevent staining. These sealers cure and won’t compromise food safety. However, sealers require reapplication after two years or less. While cured sealers present no health hazards, synthetic sealers may have volatile organic compounds (VOCs), which are toxic.
One alternative is a walnut oil/wax mix, as recommended on the “My Chemical-Free House” website. Commercial sealers include:
Meta Crème Next Generation Impregnating Sealer is a synthetic sealant manufactured by Dry-Treat and promoted as a low-odor, ultra-low-VOC impregnating material that fulfills the strictest LEED requirements. In the product literature, the manufacturer provides the following information: Waterborne Dense Stone Sealer will qualify for EQ Credit 4.2: Low-Emitting Materials: Paints and Coatings: 1 Point. The material comes with a 15-year Performance Warranty. $100 per qt. at ECO Building resources.
Sealer’s Choice Gold by Aqua Mix includes an antimicrobial branded as MicoBan. The company says the material has less than 70 g. of VOCs per L. Nonetheless, like other synthetic sealers, the material remains harmful to inhale until cured. The product costs $44 at Home Depot for 24 fluid oz. (a little less than1 qt.).
Color choices: Not all granite and stone require sealers. Dense, darkly colored counters do not need it. To determine if a counter requires sealing, you can perform a water test. This test entails seeing…
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