Copper Cladding

Mona Lemoine

Associate | Senior Sustainability Consultant

DIALOG

LEEDuser Premium Member

0 thumbs up

February 24, 2021

Dear SLD-ers,

We have a project team considering the use of copper cladding for a high profile project in Vancouver. The preference is to use pure copper that is pre-patinated and does not have additional coatings.

We are attending a CEU from the Copper Development Association to understand options and environmental impact, but we also want to tap into less biased resources. We are also exploring the supply chain to see if we can use 100% locally recycled copper to avoid the impacts associated with mining new copper.

Copper is on Perkins&Will's precautionary list so we are taking a closer look at its performance through the following lenses:

Environmental impact (in-situ, extraction, manufacturing)
Human health
Carbon impact

Current suggested manufacturers are KME, Astec, Pohl, Zahner, Northclad.

Originally the team looked at wood cladding and deemed it not feasible for the project because of maintenance concerns.

We would appreciate any input or insight on some of the questions we are looking into:

If copper is deemed harmful, what is our alternate recommendation?
Are there any finishes/manufacturing processes that reduce the harmful in-situ impact?
What are our main concerns?

Your thoughts / input would be greatly appreciated.

Thanks!

Mona

Mona Lemoine, Architect AIBC, MRAIC, LEED AP BD+C, RELi AP

Senior Sustainable Design Specialist
Material Performance Lab Co-Director

Post a reply

Margaret Montgomery

Principal

NBBJ Architects

LEEDuser Premium Member

34 thumbs up

Wed, 02/24/2021 - 19:01

Hi Mona, Look hard at the ecosystem impact beyond the upstream – it’s forbidden on SalmonSafe projects because it has a negative impact on aquatic species. I’ve heard varying things about why – one I’ve read is that it inhibits salmon in their ability to navigate and find their destinations upstream. I asked Ellen Southard at Salmon Safe and her answer was less nuanced: “oh, it kills them.” https://salmonsafe.org/ Margaret Montgomery, FAIA, LFA, LEED AP BD+C, WELL AP Principal NBBJ 223 Yale Avenue North SEATTLE WA 98109 Direct: 206.223.5230 Mobile: 206.200.4526 nbbj.com | meanstheworld.co From: Mona Le

Helen Brennek

LEEDuser Basic Member

0 thumbs up

Wed, 02/24/2021 - 19:50

Hi Mona, I can’t speak to copper impacts, but re: durable wood cladding we’ve found Accoya to be a good option from an environmental and maintenance perspective. While it is not locally treated, LCAs have reflected that the transportation impact is minimal, particularly when compared with the life cycle impacts of products that would have more carbon intensive manufacturing or require more frequent replacement. We have also been able to work with the supplier to use local wood on projects where there was a local species that had already gone through their rigorous testing. Happy to discuss further if wood could still be on the table. Additionally, if there are reasons you already ruled out Accoya I'd be interested to hear them!

Z Smith

Principal | Director of Sustainability & Building Performance

Eskew+Dumez+Ripple

LEEDuser Premium Member

4 thumbs up

Wed, 02/24/2021 - 20:59

Mona, from my days working on CIRS in Vancouver I'd been made aware of what Margaret literally labels as the 'downstream effects' of exposed copper--it's toxic for fish. At very high levels it's bad for people too. So you're wondering why it's OK for plumbing? I'm told that typically the walls of copper pipes get coated quickly with oxides etc. that inhibit Cu leaching into the water--though if the pH of the water shifts you can have problems, not entirely unlike what happened with lead pipes in the Flint water system. Incidentally, when you see copper flashing on slate roofs, you'll notice that moss growth is inhibited wherever the copper is exposed; sulfates in the air (acid rain!) form copper sulfates which are described as a "natural herbicide" on one home improvement article. Exposed Zinc has the same 'benefits', which is why exposed Zinc is also probably a bad idea.

If you're in Vancouver, you can also go up and have a look at how the wood cladding of CIRS at UBC is holding up 10 years after installation. It was clad with 3/4" thick cross-laminated FSC cedar, and during design we developed a relationship with the UBC Forestry department who was developing what they described as a non-toxic marine-grade varnish derived from forestry waste streams. The idea was that the panels could be removed from time to time, sanded if needed, and re-varnished. Sustainability doesn't mean we don't have do maintenance.