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MARK CONCRETE
Moss Landing, Calif.
www.markconcrete.com

Mark Concrete out of Moss Landing, Calif., focuses on specialty concrete projects such as countertops, fireplace surrounds and architectural details inside and out. The Mark Concrete team recently completed a countertop system for a homeowner that included a piece that incorporates an integral sink, integral copper drain board and a vein of river stones. The bay window backsplash/windowsill was cast as a separate piece.

Mark Concrete highly recommends to its customers integral color on countertop systems. "With integral color, you can go back and buff out a flaw or stain and resurface it and the countertop will look like new," says Tina Perez, production manager with Mark Concrete. Mark Concrete offers clients more than 150 integral color choices created with pigments from four different manufacturers.

The precast integral sink countertop section was poured with one of Mark Concrete's standard molds and a back form system to support the integral sink walls and bottom. The sink bottom and sides are 2 in. thick. The homeowner was looking for a thicker edge detail on this piece of the countertop system so Mark Concrete poured a 21⁄2-in.-thick top; the other pieces in the kitchen were poured at 1¾-in. thickness. Mark Concrete used 3⁄8-in. rebar and TechFab's C-Grid carbon fiber mesh for reinforcement. Perez says Mark Concrete often uses the carbon fiber mesh for secondary reinforcement because it adds to the strength of the concrete and helps reduce the risk of cracking in long sections.

An additional unique feature in the countertop was a set of copper bars to create an integral drain board. During the casting process, the Mark Concrete team created voids in the concrete mold where the copper pieces would be later inserted into the countertop. After the copper bars were placed during the finishing process, Mark Concrete secured them with a tinted epoxy to match the concrete color.

The decorative river stones embedded in the countertop were cut and polished by Mark Concrete and their placement carefully thought out so the finished appearance of the countertop and sink included a graduation of rock sizes that mimicked the different sizes of rocks you would see in a natural riverbed. Mark Concrete used a series of diamond-infused honing pads in a wet polishing process up to a 400 grit for a matte look. They finished off the countertop with a penetrating sealer and several coats of beeswax.