Weathered metal is a long-standing trend in the world of architecture and building design. By offering a natural and unique look often used as a trademark, it gives a signature feel to a building’s façade. Weathered metal is created by allowing natural chemical reactions to take place on the surface. The process can also be aided and accelerated through the use of chemicals or acids. In addition to the aesthetics, weatherization naturally seals the metal, protecting it from future damage.
Animals Always at the St. Louis Zoo features weathered metal impressions of animal representations. Photo: Randy Allen, http://rsaphoto.com/
Commonly Used Weathered Metals
Weathered metal has been part of architecture and design for decades with various applications between markets. Recently, advances to the science have produced a broader range of metals that can be used. Some of the most common metals used for weathering include zinc, copper, brass, bronze, steel and titanium.
Weathered zinc is possibly the most popular for its variety of uses, from artistic creations to decorative walls. Particularly popular in France and Germany, mill-finished zinc weathers after roughly two weeks of exposure to the natural elements, changing color and texture.
Although zinc’s popularity has grown in recent years, copper has historically been the most-utilized metal. One process for preserving the weathered copper was done with linseed oil and lampblack chemicals. This would turn the copper dark with a noticeable lustrous finish.
Brass and bronze are naturally weathering metals, often milled and unpolished. There is typically a release coating on them that needs to wear off before it starts to oxidize. These metals are commonly used for statues, art and fountains.
Terne-coated steel has a lead-like appearance when it weathers, making it an ideal alternative to the poisonous material. Although a non-toxic material, this steel has to be maintained.
Corten steel is not used as often because of the rust runoff that can stain materials around it. However, there are situations where this steel is preferred. For example, it is often used in areas prone to graffiti as it will rust, flake off and remove the markings.
Titanium is a metal that doesn’t change much from weathering, keeping the highly reflective surface look from the mill.
Each type of metal gives a different visual effect depending on the project for which it is used.
The Statue of Liberty is an example of weathered copper that was weathered naturally by the salt air.
Examples of Weathered Metal
Weathered metal is popular in projects that need to be aesthetically pleasing as well as functional. For example, it is used in statues and artistic structures around the world.
The Statue of Liberty in New York City is an example of weathered copper. It was weathered naturally by the salt air, which happened faster because of the sodium and chloride in the water. New York restoration committees have worked to keep the Statue’s patina green safe. Their focus is to keep the metal from aging further or deteriorating.
The St. Louis Zoo in Missouri is home to a menagerie statue of animals. This art piece works to showcase the diversity of the animal world. The statue is called “Animals Always” and features weathered metal impressions of animal representations. As weathered metal continues to be used in the U.S. and across the globe, it becomes apparent that this is a style that isn’t going anywhere.
Weathered metal keeps the metal low-maintenance or maintenance free by protecting it from the elements. Weathering essentially removes the work necessary for upkeep as periodic check-ins are all that are necessary to maintain the structural integrity of the joints.
The Benefits of Weathered Metals
Weathered metal keeps the metal low-maintenance or maintenance free by protecting it from the elements. Weathering essentially removes the work necessary for upkeep as periodic check-ins are all that are necessary to maintain the structural integrity of the joints. This makes it a popular choice for designers and building operators due to the lower cost and labor necessary. It is also worth noting the added green benefits of weathered metal. With environmental concerns becoming such a priority for companies, LEED
Certification becomes more of a benchmark than an award. Weathered metals are preferred for their natural characteristics and score higher with LEED. LEED certification requires a certain amount of the material to be locally sourced, and raw materials receive higher scores than the more processed alternatives, which lends directly to weatherization.
Weathering metal is a natural process that has existed for decades as a purposeful practice. Its continued use shows that this process has a variety of ways it can be utilized, while strategically providing a visual feel to the surrounding environment.
Jim VanBecelaere is the director of sheet metal fabrication at IWR North America in St. Louis. VanBecelaere has more than 50 years of fabricating and manufacturing experience that helps him run and manage the department for IWR. He is responsible for orchestrating and optimizing the workflow within the department and ensuring operational parameters are aligned with division goals and client needs. IWR is a subsidiary of MHS Legacy Group, a diversified national holding corporation also based in St. Louis with roots back to 1895. For more information, please contact VanBecelaere at jvanbecelaere@iwrna.com or (314) 633-4921.