Building to Last: Specifying Copper for Wall Cladding Applications

By 2021, it’s expected that those who design the majority of their projects to green standards of some type will rise from 32 to 45 percent. In addition to this environmentally friendly shift in building practice helping reduce carbon emissions and saving energy, it has systematically altered architect and designers’ specifications processes. One result is that architectural copper, once specified mostly for roofing systems, has evolved increasingly into a material considered for durable, long-lasting and low-maintenance wall cladding.

Here are three reasons why architects and designers should consider specifying copper for new construction or retrofit projects:

1. Energy Savings Principals

Copper wall cladding systems can help a building reduce its energy consumption. Arizona State University’s Biodesign Institute C, a 2019 North American Copper in Architecture (NACIA) award winner, is an excellent example of copper’s energy-saving benefits. The 5-story, 188,447-square-foot research facility is targeting LEED Platinum and achieving a 44 percent energy-savings goal with the help of its double-skin façade.

The design implements thousands of copper panels featuring eight different configurations of perforation. These perforation patterns were carefully calibrated and positioned to minimize solar heat gain, optimize daylighting and visual comfort, and provide unobstructed views of the campus. The natural cooling works through a 2-foot gap between the insulated metal panels and the copper screen, which creates a ventilated cavity that balances the air temperature between the two skins and the outside air. When paired with the skin’s function as a shading device, the surface temperature of the inner façade can be reduced by 65 degrees on a hot summer day. This reduction slashes the energy cost needed to cool the entire building.

Designers of the Midtown Center in Washington, D.C., a 2019 NACIA award winner, also utilized copper for an energy-saving design. The team installed a façade consisting of 10 different unit types with varying angles of copper to create a gradient pattern. The copper and glass façade is not only stunning, it also reduces peak by six percent in overlit areas, glare by 50 percent, and direct solar gains by 18 percent.

Copper and its alloys are capable of being formed into unique dimensions and shapes, such as the examples above. The highly malleable metal allows for dozens of different methods of formation, many of which are specified in the Copper in Architecture – Design Handbook, a free online resource provided by the Copper Development Association (CDA).

2. Durable Characteristics

Copper’s inherent durability makes it an excellent specification for wall cladding projects, such as the Pablo Center at the Confluence, a 2019 NACIA award winner. The design team sought to capture and reflect the movement of the Chippewa and Eau Claire Rivers located near the structure in Eau Claire, Wis. The design was achieved through a crimped copper-clad façade. The material is given further richness through its patination, a visible expression of the physical deposits that make up the local environment.

Architectural copper applications like the Pablo Center can easily last more than a century without sacrificing performance. Once installed, the metal chemically reacts with the oxygen and moisture in the air, naturally forming a protective oxide/sulfur layer. This layer, or patina, is harmless to the metal and provides a self-forming defense against corrosion. Thus, new copper isn’t needed for frequent replacements or repairs because of the long service life of most copper and copper alloy systems, reducing the strain placed on our environment. After all, the most environmentally friendly material is the one that needs to be replaced and repaired the least. Once installed, copper often requires no maintenance for its natural finish and appearance.

Over time the metal evolves from a “shiny penny” color to a brownish chocolate, before finally, in most regions of North America, turning to a light green color. Its 18 to 20 architectural alloys, ranging from brass and bronze to nickel silver, even allow for a yellow, brown, stainless steel or pewter-colored appearance. The wide variety of color options from copper and copper alloys provide architects with close to infinite choices when designing a project.

3. Ability to Achieve Certifications

What truly makes copper stand out from other cladding materials is its sustainable properties. The metal can be used for LEED credits and the WELL building standard, thereby providing a measurable option for specifiers and architects who are seeking green certifications.

For wall cladding specifically, copper can be used in several applications, including the “Materials & Resources” section. This is because of copper’s high recyclability and the ease of acquiring recycled copper, providing building professionals an opportunity to reuse a material as opposed to justifying the cultivation of virgin materials. Copper can also be applied to credits covering regional materials and innovative design.

As architecture grows more diverse, creative and sustainable, copper wall cladding will rapidly become a popular application and style. To view more examples of how architects and designers are incorporating copper in today’s building wall-cladding systems and more, visit www.copper.org.