Concrete countertops are are durable and hard wearing but the are not impervious to everything they come into contact with in a kitchen or bath. Concrete is similar to marble in that it is a porous material that is easily compromised by acidic liquids. Whether you have a precast or poured-in-place concrete countertop, you must seal it and wax it in order to maintain its food-safe quality, luster and stain repelling abilities.
Important Ingredients and Features to Consider
There are many concrete sealers on the market made with a wide array of active chemical ingredients and they are mostly for indoor and outdoor floor or structural applications. By contrast, there are relatively few concrete sealers labeled as "food safe" on the retail market. Many concrete countertop fabricators use and sell their own proprietary food safe sealants. Whether you use a proprietary sealant from your fabricator or purchase another brand, look for three key pieces of information on the product label. Check to see that a product is FDA food safe approved, that is low in VOCs or volatile organic compounds and that the product is water-based. In addition to your sealant you will need to keep on hand a good quality, food-grade carnuba or beeswax and lay down a fresh coat of the wax over your sealant at intervals of six months or so. Sealant applications vary widely from a single-step process to a three-or-more-step process. Recommended application tools vary by product but fine foam rollers are commonly recommended. A DIYer can easily apply sealants for both the initial application and yearly maintenance applications.
Examples of Products
Buddy Rhodes Ltd. manufactures a Satin Sealer product for concrete countertops. It can be used on plain, colored and textured surfaces and is a water-based acrylic formulation. It is available directly from the Buddy Rhodes and from numerous online and brick-and-mortar retailers that sell stone and stone-related products. As of 2009, a quart will cost you approximately $32 and a gallon $96. V-Seal Concrete Sealers makes a range of food-safe sealants for concrete counters marketed under the name Stonelok. These are water-based and use urethane and epoxy resins. The Stonelok sealants come in two finishes: gloss and extra low gloss or satin to fit your preference. The Stonelok products are available for purchase directly from V-Seal and can also be found at big box home improvement retailers, stone dealers and fabricators. Each finish option comes in two sizes made to cover 40 and 80 square feet, respectively, ranging in cost from approximately $115 to $189 as of 2009. Expressions Ltd., a concrete fabricator, sells a proprietary food-safe satin sealant in sizes ranging from 16- to 128-oz. bottles costing between $25 and $120 per bottle.