Concrete Overlays, Vertical Overlays

Experts figured Wes Vollmer was ready to climb the walls when he told them what he wanted to do with a microtop overlay. “They thought I was crazy,” says the owner of Alternative Finishes in San Antonio, Texas.

But for Vollmer, who was looking for an innovative application, the question was simple. “If it was tough enough to hold up on floors, why won’t it hold up on walls?” When the mix manufacturer could not think of a reason, Vollmer went vertical.

Vollmer is one of a growing number of decorative concrete craftsmen who are using vertical overlays in highly decorative interior and exterior applications. Many of the jobs are in commercial buildings, such as resorts, hotels or upscale restaurants, where clients need the look of an expensive custom home, but with washable surfaces that are as tough as concrete.

Designs are unlimited. By stamping or carving, contractors can create geometric patterns, complicated forest scenes and even faux dinosaur fossils. A huge range of colors is available using integrals or acid stains.

If you’re in the decorative concrete business, you already know the possibilities of design. The bigger questions lie beneath the surface, and one reason that vertical overlays have been successful is their versatility when it comes to substrates. “I haven’t seen anything I can’t go over yet,” Vollmer says. Substrates that take well to microtoppings include plywood, OSB, and sheetrock, the most common wall material encountered on interior jobs.

Experienced floor overlay installers will find new challenges in vertical work, and they need to be prepared. “He’s going to have gravity that he isn’t used to come up and bite him,” Vollmer says. Gravity is the key difference. There is obviously no self-leveling in a vertical application, but there are door frames, windows and counters to work around. Therefore, there is a difference in the mental approach, the preparation of the substrate and the mixture.

Prepping and mixing
One of the first considerations is the size of the job. For example, an installer facing a large surface area may use a sprayer to shoot material from a hopper while a trowel crew follows behind smoothing it. For smaller areas, applying by hand may be preferable.