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When IBEW 48 upgraded their training center in Portland, Oregon, they chose a unique look, three copper signs with the IBEW logo and three interior walls covered with copper panels. Two 23-foot by 10-foot copper walls accent the hall’s training room, with large TV screens to display lectures. The third wall is in a conference room where IBEW leaders meet with elected officials. “The conference room is their showpiece,” says Shane Crunchie, project manager for General Sheet Metal (GSM) in Clackamas, Oregon. “And its 23 feet by 11 feet copper wall was the architectural focal point. It had to be perfect.” 

The architect’s original plan suggested 16-ounce copper, which concerned GSM. “We worried that 16-ounce wouldn't hold up over time in a room with people walking by the wall and bumping into it,” Crunchie says. Early in the design process, which started around May 2023, GSM recommended moving to a more durable 48-ounce copper. GSM also designed the custom support structure for the panels. “There's an aluminum clip system behind the copper. The finished copper is glued to aluminum panels, and they're hung in sections. Wherever we had aluminum panel joints, we glued a piece of copper in place in the field.

The green patina that forms when copper is exposed to air stabilizes the copper chemically, making it easier to handle. “Copper starts to oxidize almost immediately after you sand it,” Crunchie says. “But in the submittal process we learned that IBEW 48 didn't want the patina finish. They wanted to see the brightness of the copper. That created a level of complexity for the project because of the finishing technique.” The owners also wanted a hand-sanded finish to bring out the metal’s natural color variegation. “You had to finish it very carefully to get it to work.” 

GSM worked closely with the customer throughout the design process. “We did multiple phases where we started out with various samples with patina,” Crunchie says. “That’s when we discovered their desire for a bright finish. We produced more samples with the bright finish with appropriate clear coat.” Before starting production, GSM fabricated a full-sized demonstration panel for the owner’s approval. “When we brought out our first panel, we hung it and did our first in place inspection before we went further down the road. The client was in lockstep every step of the way. We always try to make sure there are no surprises.” 

GSM developed a quick process for finishing the panels because the clear coat had to be applied while the copper was freshly sanded. “We set up equipment specifically for this project,” Crunchie says. “Anytime you're doing that, I would advise that you spend the money on what you need and be prepared to make adjustments mid-process to your plan, fabrication or installation method based on something that nobody saw earlier in the process.”

The team did the preliminary sanding in the open shop, then wrapped each piece in brown paper for moving to the coating tent. Throughout the project, other teams were fabricating duct in different parts of the busy GSM shop, so the coating tent was pressurized to mitigate dust. “We had a four-step cleaning process before we were able to apply the coating to the panels,” Crunchie says. “Finishing the panels was a white-glove process, and everybody had to be trained and brought up to speed.” Only experienced people touched the sanded copper. “You have to have a group of people who know how to navigate the different variables, because sometimes you're learning in real time,” he says. In this case, “a single fingerprint could cause a chemical reaction on the face of the copper that would create a blemish.” The clear coat was allowed to dry and harden before the team mounted the copper onto the aluminum panels. 

The copper walls were the most technically challenging part of the project, but GSM also installed roofing panels, gutters, downspouts and a stainless-steel rail. 

The company fabricated everything except the roofing panels in their own shop. The project required 2,887 pounds of 48-ounce copper sheet, 2,432 pounds of 5052 aluminum and 200 pounds of stainless steel. “It was labor-intensive,” Crunchie says. The $250,000 project ran from July 2023 through February 2024 and brought GSM 600 work hours in the shop and another 600 work hours in the field for a total of 1,200 work hours. 

"Ultimately, the client was very happy with us, and the general contractor was very happy with us,” Crunchie says. “They said they couldn’t have hired anybody else to do this project.”