Some people and organizations have a knack for seeing the future. Good business fortune is rarely pure luck. Often it’s the result of strategies that anticipate and respond to emerging market trends.
Over the past decade, a commitment to working with architectural zinc has helped some forward-thinking contractors, panel fabricators and metal distributors grow their businesses. A key to success for these companies has been their ability to identify, develop and integrate new products, materials or applications into their services.
Business of Gray Exteriors
Growing beyond just a specialty metal, architectural zinc-or titanium-zinc alloy-has become a preferred metal of many contractors, architectural designers and building owners. Well-suited for exterior applications, zinc’s “best value” may be façade cladding, where its natural gray aesthetic and durability is unmatched by coated-metal alternatives. Even in a struggling economy, the business of building green continues to evolve. This new paradigm shift further stimulates the growth of those metal companies that have embraced this Old World yet contemporary architectural metal. Zinc is nature’s gray metal- and it’s here to stay.
Gray Alternatives
It can be said that imitation is the greatest form of flattery. In the architectural gray metal market, it is zinc that sets the standard for natural gray metal. A century ago, the demand for a nonstaining, malleable architectural metal helped create lead-coated copper. Even before lead coat fell out of favor amid environmental liability issues, additional gray metal alternatives appeared as challengers:
• Zinc-tin coated copper
• Zinc-tin coated stainless steel
• PVDF-coated steel/aluminum or painted metal
Virtues of Zinc
Architectural zinc is a malleable sheet metal that has been used on the exterior of European buildings for almost 300 years. Zinc is a natural weathering metal that forms a beautiful warm gray patina after exposure to water and free-flowing air. Valued primarily for its natural gray aesthetic, zinc provides a long service life, which varies by application type and rainwater erosion. Other benefits of zinc include ease of fabrication and maintenance; clear stormwater runoff; economical first cost; high salvage value; and time-tested performance.
Natural Color
Zinc provides a natural gray color without the use of any synthetic color coating. The zinc carbonate patina provides the characteristic variegated warm-gray color. Gray generally carries a neutral tone. As such, it’s this neutral quality that helps gray materials complement other more-dominant colors. Gray can look great alone or help other materials look their best. As the primary color theme or as a complement to other natural materials, zinc has the character that can’t be imitated or synthetically reproduced.
Monolithic Material
Titanium-zinc is a monolithic metal that helps zinc retain a low- to no-maintenance aesthetic. All exposed metal surfaces, including scratches and cut edges, will form the gray patina, reducing the need for outside interference. Recycling zinc scrap or damaged panels is much less polluting as no synthetic coatings are incinerated.
Durability
Good design and quality materials are two requirements for durable construction. Zinc’s durability provides a long-term natural aesthetic that requires little or no maintenance.Durable materials like zinc provide a lower life cycle cost than lower-quality alternatives. As a wall cladding material, zinc can be expected to last for centuries.
Green Thumb
Zinc has a low primary energy content compared to other architectural metals. Capable of eliminating all waste, with 100 percent scrap recycling possible, zinc promises to be the environmental leader of the architectural metals industry.
Zinc Cladding Profiles
Heavy-gauge zinc rainscreen panels provide a service life topping 200 years. For shorter service requirements, such as 150 years, light-gauge zinc cladding may provide an economical alternative. Light-gauge rollforming equipment provides an economical way to fabricate some interesting panel profiles. With the ability to alter the orientation of the panel seams horizontally, vertically or diagonally, architects can achieve inspiring wall elevations with light-gauge zinc, as well. Some of these zinc profile alternatives include:
Corrugated
Common sinusoidal profiles have heights of 1/2, 3/4 and 7/8 inch
(13, 19 and 22 mm), with a typical frequency of 2.67 inches (68 mm). Trapezoidal, or box-corrugated, profiles for wall applications vary widely in profile but generally are deeper and higher-1 inch
(25 mm) plus-in section and provide a much stronger shadow effect. Either profile will provide the zinc sheet with greater rigidity and strength. Both signwave and trapezoidal corrugated profiles are an excellent way to maximize panel strength while minimizing metal cost with light-gauge (0.028 to 0.031 inch [0.71 to 0.79 mm]) zinc.
Standing Seam
Vertical standing-seam pans, using the singlelock or double-lock seaming method, long have been used for roof applications. Using this familiar profile on the wall surface with seams oriented horizontally-or vertically for shorter panels-makes a very cost-effective zinc cladding. Given the optimum drainage plane, the single-lock, or angled-seam, installation method is preferred to allow maximum horizontal panel movement. With a 1-inch seam height, standing-seam pans are typically 12 to 16.7 inches (305 to 424 mm) wide. For zinc snap-seam profiles, consult the panel manufacturer for information regarding the acceptance of zinc specific to that seam type.
Flush/Reveal Panels
Architects looking for a monolithic natural gray wall with minimal shadow lines often choose a flush, or hairline joint, panel. Similar profiles with extended “male” lateral edges will create a reveal or recessed seam. Both profiles can be installed in a horizontal or vertical orientation. Shorter panels can be through-fastened at the bottom female S-lock joint. Longer lengths
(> 10 feet [3 m]) should consider using a sliding clip to accommodate thermal movement. To balance oil canning and material cost, the face dimension (usually 8 to 12 inches [203 to 305 mm]) and material thickness (0.03 to 0.04 inch [0.8 to 1 mm]) should be coordinated. Opportunities to stiffen the profile can be achieved with panel-end return bends.
Interlocking/Flat-Lock Tile
Flat-lock wall tiles provide an easy-to-install dry-joint wall cladding solution. Interlocking tiles are a popular profile choice, with many sizes, shapes, metal thicknesses and orientation patterns. Flat-locks offer numerous design alternatives. Interlocking tiles can be fabricated into various shapes, including rectangles, squares and diamonds, but bear in mind that the time required to cut, notch and fold interlocking tiles makes them more costly to fabricate than rollformed profiles. Indirectly attached with concealed clips, flat-lock tiles provide a low-tech profile with built-in expansion provisions at every joint. Interlocking tiles offer a zinc solution with character provided by extra texture and seaming patterns.
The Time Has Arrived
As those businesses experienced in architectural zinc continue to prosper, new fabricators, installers, distributors and metal profiles will enter the market. Zinc is a natural metal, and its time has arrived. Working with designers who want to use natural materials, light-gauge zinc will be a material that provides maximum value in a tough economy. With green building a value of the present and future, the color of architectural metal is looking very gray.
Steve Shull is the regional sales manager for RHEINZINK America Inc., Woburn, Mass. For more information, visit www.rheinzink.com.
