Concrete Floors, Concrete Burnishing

For many years, burnishing has been commonly used to make commercial floors harder, more durable and easier to clean. But these floors had no aesthetic value. They didn't need to; they were an underlayment.

"In the old days, they burnished concrete for structural value," agrees Tom Ralston, president of Tom Ralston Concrete, a third-generation concrete company in Santa Cruz, California. "The more you trowel concrete, the harder and the more abrasive-resistant it becomes."

But in addition to this incredible hardness, something else happens to the surface's appearance, says Ralston, a frequent speaker and trainer of decorative concrete techniques at industry gatherings. "We found that burnishing really mimics acid staining in that it creates a kind of patina-like variegation that people are looking for these days." He recalls one client who wanted a variegated-looking countertop some years back. With the help of a spray bottle, "We found we got a nice variegation with gray natural concrete just by adding water." The more they burnished — with a burn trowel typically three inches wide — the more variation of color they got.

Ralston, who is always scouting for new products and techniques to help him with his one-of-a-kind creations, was definitely onto something that went beyond the basic burnishing of yore.