Copper roofing is renowned for its durability and energy efficiency, but it’s also one of the rare roofing materials that looks better with age. This is all thanks to a process called patination, which WiseGeek.com defines as:
“…films that develop on the surface of a metal, wood, or other substance over a period of time. In many instances, the development of a patina is considered desirable and may actually enhance the value of the item.
One of the more desirable forms of patina have to do with the gradual development of a brown or green film on metal objects. Due to exposure to open air and the natural process of oxidation, an aged metal such as copper and bronze tend to develop a patina that is often a pleasing shade of green. Domes and roofs on buildings that feature sections of copper tend to develop this green shade over a number of years. The color is often anticipated in the original design of the structure and is an effect that the owners look forward to taking place over time.”
As a naturally occurring process though, patination can take around 7-9 years to develop on roofing in Salt Lake City, even with the area’s salt water environment. Fortunately, you can hasten patination by chemical means through the application of ammonium sulfate, cuprous chloride, ammonium chloride or hydrochloric acid bases to copper roofs.
Be warned though: artificially achieving patina requires precise chemical application and the end result is greatly affected by a locale’s weather. To achieve the best look possible, rely on Salt Lake City roofing experts like Oakley Roofing that specialize in patina finishes. The company has a metal fabrication shop which allows its experts to install copper roofing as well as apply the patina finish afterward. The company is considered a one-stop source for all things related to copper roofs.
(Source: What Is a Patina?, WiseGeek.org)