Article No: 172

2006-05-03 10:09:15
Decorative Concrete
By: Cindy Rizzo with Jan Bloom


Choosing materials that are appropriate to a region and a home's design add the extra touch that ensures the "wow" factor. And, when the home is luxurious and incorporates a number of custom features, it's even more important for the hardscape to reflect the elegance and detail of the entire property.

The Texas Tuscan model home was designed for the San Antonio Parade of Homes by Gustavo Arredondo, a leading residential architect in the Hill Country and South Texas area, and built by John Long of J. Long Builder, Ltd. The exterior is crafted of a combination of Old World stone and European-style stucco that is capped with a barrel clay tile roof. The home's 8,000-square-foot circular motor court and driveway is just one part of the contiguous hardscape. In addition to the driveway, the hardscape includes about 2,500 square feet of covered patio and porches, a 1,500-square-foot pool deck, and a 450-square-foot detached gazebo. Mike Logsdon, owner of Land Design Texas and the master plan designer who created the hardscape for this outstanding property, says, "Installing imprinted concrete allows a limitless palette of colors and textures, so I can create an exotic look at a fraction of the cost of natural materials."

Upscale style without the high-end pricing
No matter the final cost of a home's construction, everyone has to work within a budget. Some choose to put the extras in the master bedroom and bath, while others invest in high-end kitchen fixtures. But talk with any real estate agent, builder, contractor or homeowner and they'll all say that the appearance of the front of the home is very important. That's why drive-up appeal increases property value.

In many cases, the driveway is the first opportunity to make an impression that sets the tone for the entire residence. At this property, the large motor court and driveway, as well as the rest of the hardscape, was designed to coordinate with the clay tile roof. Not only does the combination of colors harmonize with the roof tiles and enhance the home's appearance, it's a color that hides tire marks, a particularly good idea for driveways.

Combining architectural concrete
and natural materials

Natural Oklahoma stone was used on the facing of the vanishing edge and beach-entry pool, the pool's coping, and spa. The balance of the hardscape was constructed of architectural concrete that was textured with patterned skins and defined-edge tools. The slate pattern for the architectural concrete was cut and colored to emulate the natural stone of the pool in order to create a seamless appearance.

The architectural concrete of this motor court and driveway was crafted to look like natural stone using a distinctive Pennsylvania Slate pattern from the Lithotex Pavecrafters imprinting tool set manufactured by L. M. Scofield Company. The Pennsylvania Slate set consists of 30 different single-stone, prestige tools that vary in size from 6-by-6-inch pieces to 3- and 4-foot stones. This modular pattern enables contractors to create unique designs by picking and choosing specific tools from the set, or using all 30 tools in different combinations. Before imprinting this project, the contractor used the tool set pieces to develop a design that emulates the appearance of natural stone. It took a seven-man crew three days to place, color, imprint and seal this driveway.

The installation process
Clearly, installing an 8,000-square-foot motor court and driveway is a large project. Timing is a particular challenge because temperature and humidity are critical for the installation of architectural concrete. For this project, the first step was to place the uncolored concrete base. This involved placing the concrete and floating the surface. After the uncolored base has had some setup time--from 20 minutes to an hour or more depending on weather conditions--it's time to broadcast the first color of Lithochrome Color Hardener.

The contractor chose a dry-shake color hardener because it provides intense, opaque colors and improves durability. On this driveway, the first color broadcast over the uncolored concrete surface was Scofield's Arizona Tan Lithochrome Color Hardener. A short time later, more of the same color hardener was troweled in. Next, the second and third color hardeners, Russet and Terra Cotta, were flashed onto the surface and floated and troweled in. The colors were chosen to match the mottled appearance of the roof tiles.

A stone's texture extends to its edge. The same should be true for the edges of every textured architectural concrete project. In other words, be sure that the texture reaches completely to the edge of the surface. With a large project like this, which required about six separate pours, embossing skins matching the face texture of the imprinting tools are used to imprint the edges first. Then, the defined-edge tools are placed according to the pattern design.

When imprinting architectural concrete, it is necessary to use a release agent on the skins as well as the defined-edge imprinting tools. Release agents prevent the tools from sticking to the concrete surface or pulling the concrete up when they're removed. Clear liquid release agents can be used when you want to see the underlying concrete color. To change or add another color, you can add powdered color to the clear liquid release or use powdered release agents. Colored powdered release agents give the surface a more natural look and they have the added benefit of increasing the appearance of depth.
Finishing touches
Before the release is washed off the surface, it is important to detail the imprinted work. What does that mean? In some cases, that means having a member of the installation team follow behind the people imprinting the surface and clean up and remove any material that has squeezed between the margins of the tools. When detailing is done depends on weather conditions as well as the timing and staffing of each project. Most stamp tool manufacturers also offer the hand tools needed for detailing imprinted concrete.

Once the surface of each pour has been imprinted and detailed, let the substrate set for at least 24 hours. Then, wash the release off of the substrate and clean the surface. Once any extra release has been rinsed off the surface and the surface is completely dry, it's time to apply the sealer. Make sure that sealer is applied to a clean, dry surface. That might mean washing the surface again or blowing away any debris that has accumulated.

Be sure to choose a sealer that is compatible with the rest of the materials you've used for your project. Most decorative concrete manufacturers offer a complete line of products that works together as a system. This approach helps to ensure a more long-lasting result. Sealer can be rolled onto the surface or applied with an airless sprayer. As a general rule, apply multiple thin coats of sealer because they work more effectively to protect the substrate than fewer, heavier coats of sealer. Sealers protect imprinted surfaces from stains like automotive oils and can improve the surface's durability as well as enhance its color.

The beauty of coloring and imprinting concrete can take an otherwise ordinary exterior and turn it into something special. Intelligently designed and skillfully installed hardscapes not only improve the home's appearance, they can also add to its value.