Each year, the Copper Development Association recognizes a handful of new and recently restored buildings in the U.S. and Canada that use architectural copper and alloys in their design.

Award recipients include a variety of government buildings, academic facilities, houses of worship, upscale residences and many more — most of which are now considered historic landmarks. But why is it that so many landmarks use copper?

Sometimes called mankind’s oldest metal, copper delivers beauty while providing durability, longevity and malleability, making it a preferred building construction material. For centuries, copper elements have contributed to a project’s architectural significance and have been prominently showcased in the landscape of building design.

“Copper’s natural patina has a very attractive appearance as it ages, and also when it has aged,” said Nick Lardas, owner of roofing and sheet metal works company Niko Contracting, located in Pittsburgh. “What makes it most attractive though, is that it’s a lifelong material — a copper roof can last for more than 100 years if it’s built right.”

While copper may add a sense of grandeur to any building, it is also widely known for its durability.

Durable, beautiful 

Outdoors, copper and its alloys like brass and bronze can withstand harsh exposure to the elements and wear from constant use better than most other materials. It will not rust, yet gradually, copper attains an attractive, stable green color or “patina” that enhances the appearance of statues, roofs and other decorative and architectural applications.

The CDA recently honored the Old St. Louis County Courthouse in St. Louis with a North American Copper in Architecture Award for the restoration of its vintage copper roof. Constructed in 1828, the courthouse is considered one of the country’s most prominent architectural landmarks, as it has been the site for several important legal cases, including the first two trials leading up to the Supreme Court’s Dred Scott decision, which dealt with the legal status of slaves. Originally, the courthouse roof was designed using a tin and timber roof structure. The National Park Service replaced the original roof with copper when it took the building over as part of the Jefferson National Expansion Memorial in 1941. In order to preserve this important landmark, the park service sought to design a replacement roof with the intention of staying true to the building’s historic design. Because of its durability and longevity, copper was selected as the replacement material.

While all structures experience wear and tear over time, architects and contractors can trust copper will not deteriorate or corrode with age. As a result, this metal is often used on buildings designed to last a lifetime — or longer.

“Copper has been chosen throughout history because it’s a very long-life product, and also because it’s one of the easier sheet metals to work with in terms of forming, joining and soldering,” said Lardas, who has worked with the metal for more than 40 years.

Government buildings

In 2006, the Library of Parliament in Ottawa, underwent a major restoration on one of the most prominent features of its structure — its copper roof. First opened in 1876 after 18 years of construction, the main objective was to give the library 50 additional years of life. Since a properly designed and installed copper roof should last upwards of 100 years or more, the newly installed copper roof should still be performing as intended for years to come. Eventually, the roof will feature a natural patina, typically associated with many of the buildings on Ottawa’s Parliament Hill.

And because copper is highly recyclable, much of the former copper roof was reused by Canada’s war museum in that building’s interior.

Copper is also often used because it is extremely malleable and formable — it can be formed, bent and stretched into complex and intricate surfaces without breaking. This makes it possible to easily create spires, steeples, domes, non-linear roofs and walls, as well as complicated dormers and fascia.

In 2012, the Massachusetts Statehouse — once called the “hub of the universe” by Boston author Oliver Wendell Holmes Sr. — completed a new roof restoration. Erected in Boston in 1795, the dome was originally covered by wood shingles and later, gold leaf. However, in 1801, it became the first building in North America to have cold-roller copper applied. The roof on the statehouse is unique in design and functionality. Twenty- and 32-ounce copper adorns the majority of the Statehouse because of its workability, aesthetic appearance and historical significance to building itself. The design protects the contents below and preserves the historic nature of this monument to American history.

“Throughout time, mankind has used copper to protect and adorn our most important, most prominent, most influential buildings — many of which in the U.S. are recognized as national historic landmarks,” said Andy Kireta Jr., vice president of the copper association. “Ellis Island, the U.S. Capitol, New York’s Plaza Hotel, the Massachusetts Statehouse, the Old Courthouse and many others — iconic buildings that played notable roles in the birth and growth of the United States, continue to look to copper for lifelong protection and lasting beauty. Because of these same attributes we continue to see copper being used in new and innovative ways, from intricate wall-cladding systems to interior applications on buildings that are likely to be our historic landmarks of the future.”

 This article was supplied by the Copper Development Association. For more information about copper in architecture, visit www.copper.org