Cast in place concrete countertop installation by Dave Pettigrew, Diamond D Company. Kitchen Design by Marty Fiorovich

Cast in place concrete countertop installation by Dave Pettigrew, Diamond D Company. Kitchen Design by Marty Fiorovich.

The Secrets of Concrete Countertops

Handcrafted and distinctly unique, concrete countertops are finding their way into more and more homes and commercial venues. The versatility of the medium, as well as its unpredictability, is part of the attraction. It's a growing trend and proving to be a boon to concrete artists.

Jeffrey Girard, owner of FormWorks L.L.C. in Cary, North Carolina, says, “The number one feature of concrete countertops is that they are completely customizable — any shape, size, thickness, embedded items. If a client wants cobalt blue, I can give it to them. If they want something that looks like a beach with seashells and beach glass, I can do it.”

“Concrete can give a real ‘Old World' feel,” observes Tom Ralston, owner of Tom Ralston Concrete in Santa Cruz, California. “It's one of the most unique surfaces in that no one else will have exactly the same thing.” Ralston has embedded seashells, exposed the aggregate, hand troweled a finish, polished the surface, and sand- and glass-blasted the surface, all to achieve different effects.

Stuart Zumpfe, president of Concrete Effects Inc. in Langhorne, Pennsylvania, has impressed real ivy leaves, used traditional stamping skins, and embedded coins and custom tiles into countertop surfaces for distinct results. On one job, he reports, he sprinkled titanium dioxide on the surface before sealing to achieve a gold-flecked look.

Various contractors also use integral color, acid stains, color hardeners and micro-toppings. There is virtually no limit to what you can create.

Want to know a secret?
Mix designs, construction techniques and surface treatments vary from one concrete countertop fabricator to another, and many closely guard their proprietary methods as trade secrets. But for those curious to learn more about crafting concrete countertops, there are some basics. For example, concrete countertops are either cast-in-place or pre-cast and installed after curing. Advocates for each method cite various benefits.

Dave Pettigrew, owner of Diamond D Company in Watsonville, California, pours concrete countertops in place. “I like to pour-in-place because I can form the countertop to anyone's particular needs — radius edges, curved corners.” Because he pours the countertops in-place, Pettigrew says he doesn't pour with joints. “We put plastic over the cabinets, we pour one-and-a-half inch thick, and we tell the customer we have to have control of it for 10 days.” Having control for proper curing is important.

“Sometimes form-setting on finished cabinetry is challenging,” reports Ralston, who also pours in-place. He also says “working within the framework of people's schedules — scheduling with the cabinet installer, plumber, electrician, and dry-wall installer — especially on a remodeling project, can be tricky.”

Zumpfe pours in-place and borrows a trick from pool installers for nice rounded edges, he uses coping profile form liners.

This example of a precast concrete countertop by James Humber is simple in design. However, it shows off a dramatic granit look simply by adding the right stuff to your mix.

If you want control, however, pre-cast is probably the way to go. When you pre-cast “you can control everything about the structure — the environment, temperature, curing time and how it cures,” explains Karen Smith, sales and marketing director for Countercast Designs Inc. outside of Vancouver, British Columbia. Another upside to pre-casting is that you can incorporate integral sinks into the countertop. “You can't do that when you pour-in-place,” she says, “because [when you pre-cast] everything can be accessed from all sides.”

Manufacturing time for pre-cast countertops can run six to seven weeks, but is generally five weeks, according to Smith. Forming and templating time takes about a week. Curing takes four weeks. Seams in pre-cast countertops can become part of the design. Generally, a silicon or latex caulk is used.

Girard, who is also a professional civil engineer, says the quality of the final product depends on how well the concrete is mixed, poured and cured. He advises, “Most concrete is used for structural applications. Countertops are structural and need to be approached that way.”

Another advantage to pre-cast is the ability to ship product to faraway locations, though shipping costs can be a limiting factor.

As Pettigrew points out, quantity may be the deciding factor for many contractors. “We do maybe three or four concrete countertops a month, so we pour-in-place. If I did 25 a month, I might pre-cast.”