Making GFRC Panels Decorative
GFRC panels can be given nearly any decorative treatment as normal concrete. The application dictates what works best:
- Architectural panels are often cast using various form liners. The surface finish can be sand blasted, acid etched, or polished. Various tints of gray, white, and buff can be achieved using colored cements or pigments.
- Many GFRC ornamental pieces are shot or cast using white cement and light color tints. Stone or clay brick pieces can be embedded in panels, although consideration should be given to the differential shrinkage characteristics of the different materials. Many different architectural features are best produced using GFRC.
- Countertops are typically made using a face coat and a solid integral color is often the method of choice. "We use integral color in the face coat," said Mike Wellman, Concast Studios, Oceana, Calif. which makes countertops and fireplace surrounds. "Sometimes we will do an acid stain but the majority of our clients stick with the straight integral color." Wellman typically polishes the countertop to a high gloss finish, but offers many varieties. Read more about Concast Studios' work.
- Countertops can be produced without the facing coat, although if polished the fibers will be visible. "Some of our customers like the fibers to show," said NEG America's Mike Wellman. "If it's acid etched or acid washed, they don't mind the fibers and they actually blend in with the color."
- With face coats, broadcasting aggregate or embedding decorative elements is a good choice. "Since I'm spraying in the initial face coat I'm able to broadcast aggregate in which lets me get flowing movement," said Wellman. "I can sprinkle in glass or seashells and when polished and exposed it gives the illusion of movement. With wet cast it's trickier to get that movement and make it look good."
- Rock features typically use GFRC panels that are sprayed against molds made using real rock features. Steve Holmes, vice president of Eldorado Wall Company, a Boulder, Colo. maker of rock climbing walls, says that the first coat they spray has no glass fiber. "The chop gun has mud-only and mud-and-glass triggers. The first thin coat has no fibers then we bring the thickness up to ¾-inch nominal with the GFRC mix."
- To create rocks, the GFRC panels are mounted on a structural steel framework. "The panels can be oriented in different directions," said Eldorado Wall's president John McGowan, "then we plaster the seams and sculpt them to blend the panels into a rock feature." To create the patches, said Holmes "we place lath and rebar into the seams then start with a scratch coat then apply the sculpt coat. This is done with a field mix based on a shotcrete recipe." Coloring the rocks is done with a variety of techniques Eldorado has developed over the years.
- Jim Jenkins of JPJ Technologies teaches artificial rock making. His method, however, does NOT use GFRC but rather a composite fiber-reinforced polymer concrete material that he invented and has perfected. "Our panels are ¼ to ½-inch thick," said Jenkins, "where a GFRC panel will be 1-1/2-inch thick. Our material can be cut easily with a circular saw and yet is stronger than GFRC. The seams between panels are patched with the same material used to make the panels so they behave, look, and stain the same." A sister company, Synthetic Rock Solutions, sells premanufactured rock panels that can be used to assemble rock features.
- Coloring rock and water features entails a lot of artistry. Multiple colors and techniques are blended to produce realistic color, as described in "Geo-Illusions" in the December 2007/January 2008 issue of Concrete Décor.
- Ornamental GFRC fireplace surrounds have become very popular, due to their light weight and durability. Check out what Sierra Concrete Designs does with this application in the article Surrounding Fireplaces With Beautiful Decorative Concrete Work.
GFRC countertops can be finished using virtually any decorative concrete techniques. Absolute ConcreteWorks in Seattle, WA
Although the structure for this climbing wall has all of the appearance of real rock, modular handholds are attached for climbing. Eldorado Wall Co.
Artificial rocks require artistry in color application to obtain a realistic appearance. Synthetic Rock Solutions in Amity, OR
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