Inspired by the canyons of the desert southwest, the copper rainscreen of the Health Sciences Education Building at the Phoenix Biomedical Campus in Phoenix offers lessons in evocative design and sophisticated construction techniques. The judges described the use of copper on this project as “delightful” and “lovely.” Headed by Paul Zajfen, FAIA, the Los Angelesbased CO Architect team toiled to design a building that represented the surrounding Sonoran Desert and met the harsh needs of a difficult environment. “The goal was to create a building that was of the place, that was uniquely Arizona and uniquely urban,” says CO Architect associate principal Arnold Swanborn, AIA, LEED AP BD+C. “The desert became a metaphor to capture the essence of the mountains that are north of Phoenix. And to create a microclimate within the building. If you go to these slot canyons, they are significantly cooler because of their self-shading nature. The copper skin of the building was an emulation of geological time.”
Drawing on the inspiration of the canyons in Arizona, the building aligns on an east/west axis and has a central “canyon” that runs through the middle. Each wing of the building has been further cleaved to create more canyon-like walls. The result is that the glazing is shaded by the building, yet plenty of natural light filters deep into the interior. Just as one would find in a canyon area.
Holding the design together is the copper rainscreen, which wraps the entire building and comprises approximately 250,000 pounds of copper arranged in 26 panel configurations. Jenna Knudsen, AIA, LEED AP of CO Architects says: “The copper is a unifying element that is essentially the same. To afford it, we had to keep it to a minimum number of panels, but wanted it to look random. We didn’t want it to look like four different buildings.” The rainscreen fabricator, Kovach Building Enclosures, Chandler, Ariz., created multiple mock-ups and assigned specific panels to specific points on the building. But the sophistication of the rainscreen went way beyond that. “We wanted to create a copper skin that was self-shading, so the pleating is part of that,” says Arnold. “The random nature of that is an emulation of the geology.” Knudsen continues, “We worked closely during design with the trade contractor and went through a series of visual and performance evaluations of the panels, including depth of the crinkles to bending to the patina.”
The pleating is an essential part of limiting the sun exposure, creating shaded areas, but also adding considerable visual interest. The louvers on the sun-exposed elevations continue that experience. The rainscreen is a drained and back-ventilated assembly that has open joints to allow moisture through. The air space behind allows circulation, so the rainscreen with its pleats and bends protects from heat gain, shading the wall and allowing the circulating air behind it to keep the building cooler. The whole assembly underwent a very careful analysis of moisture and temperature that helped provide information on the correct material thicknesses, configurations and selections.
While the copper skin is the defining element, the building functions beautifully because it was designed from the inside out, with each interior space carefully assigned for need and size. In that way, the design team was able to deliver light where it was most needed and limit heat gain in areas with large spaces.
As Knudsen says: “Copper did so many things. It’s aesthetically beautiful, it sort of twinkles, and it does these certain things. We picked it because it was reminiscent of the landscape around Phoenix, but it also met these criteria for building in the desert and for institutional buildings, such as sustainability and low maintenance. I think for this project it really was the perfect material.”
Health Sciences Education Building, Phoenix Biomedical Campus, Phoenix
Completed: June 2012
Building Owner: Arizona Board of Regents
Architect: CO Architects, Los Angeles, www.coarchitects.com
General contractor: Joint venture with DPR Construction, Phoenix, www.dpr.com, and Sundt Construction, Phoenix, www.sundt.com
Metal panel fabricator/installer: Kovach Building Enclosures, Chandler, Ariz., www.kovach.net Copper Supplier: Revere Copper Products Inc., Rome, N.Y., www.reverecopper.com
