Custom Curtainwall Facade Reduces Carbon Footprint on The Gateway Project

At UC Berkeley, construction of the Gateway, a new academic building that will house the College of Computing, Data Science, and Society, is underway, and as the temperatures heat up for the summer, the project is about to don a unique “jacket”. Led by Weiss / Manfredi, the project’s Design Architect, and Gensler, the Executive Architect, the wrapping of the 400,000sf building is a custom curtainwall façade that has a reduced carbon footprint as compared to the industry average considering the specific facade design of the project – and touts the documentation to prove it.

Environmental Product Declarations 

At the Gateway project site, general contractor Turner Construction (Turner) is monitoring the building’s carbon footprint by tracking environmental product declarations (EPDs). These documents disclose a product’s life-cycle environmental impacts across various impact categories, such as global warming potential (GWP). Clients, contractors, and the community can review EPDs and compare the environmental impact of a specific product against a given baseline, such as industry average data.

The curtainwall trade contractor, Permasteelisa North America Corp. (PNA), made the decision early in the project to take this transparency one step further and create a project-specific EPD, rather than simply provide industry-wide data. According to PNA, the EPDs for this component of the Gateway façade are the first known project-specific EPDs for individual curtainwall panels produced in North America. Whereas standard curtainwall EPDs look at typical construction materials, sources, and quantities, and apply mean values to determine an estimate of its GWP, PNA spent nearly six months working with its engineers and third-party reviewers to produce first a design-phase LCA and then a project product-specific, supply chain-specific EPD of the assemblies to be used on the Gateway. And the results are in – the Gateway’s curtainwall achieves a 15% reduction in GWP as compared to component averages found in the embodied carbon database, EC3.

Like Turner, PNA has carbon reduction commitments, and the level of effort to achieve this milestone was an easy choice for the firm. “It is critical for the market to have life cycle assessments and EPDs for baselining purposes,” said PNA Sustainability and Physics Leader Andrea Zani. Accuracy of the source data is important, too, if the industry is looking for true baselines. “We have seen average curtain wall EPDs with generic source data being applied to custom fabrications, but the Gateway’s EPD is project- and factory- specific. Our analysis is specific to the materiality, size, and location of these project’s panels, and the facilities manufacturing these products,” adds Zani. 

Sustainability in Buildings and Facades

With buildings accounting for 39% of the world’s carbon emissions (World Green Building Council, 2019), construction companies like Turner and PNA have made commitments to reduce their environmental impact. Tracking and baselining is a key first step, but implementing action to cut emissions is required next. Through engaging with manufacturers, vendors, and suppliers up and down the supply chain, Turner and PNA are seeking lower-carbon alternatives for standard building materials – glass, aluminum, steel, insulation, concrete, and other cementitious products. On the Gateway, PNA is using framing members coming from billets smelted using low-carbon electricity (90% renewable electricity from hydro and solar) with 35% (combined pre- and post-consumer) recycled aluminum extrusions. In addition, PNA is sourcing flat glass with 30% less carbon emission than US National Glass Association average. Turner also has implemented its own transparency practices on the project; by tracking its monthly jobsite carbon emissions across all trade partners, Turner has been able to quantify how much carbon it’s saved through its various on-site efforts, such as utilizing an all-electric track loader by Bobcat, electrifying activities like welding and dewatering, and requiring renewable diesel for all on-site equipment.   “Greening our construction practices isn’t just the responsibility of the designer, owner, contractor or subcontractor,” says Emi LaFountain, Turner’s West Coast Sustainability Strategy Manager. “Each one of us should take ownership in exploring and pursuing reduction opportunities within our scopes of work.”

What’s Next

Building certifications such as LEED, WELL, Living Building Challenge, Passive House, and Fitwel use custom scorecards to track building sustainability metrics, standards, and initiatives. Beyond the energy and materiality discussions of these certification systems, firms like Turner are committing to timelines to electrify fleets, reduce jobsite water and fossil fuel consumption during the construction phase, and maximize waste diversion from landfills, through reuse or refurbishment first, and recycling as a last option. In addition, Turner engages with a variety of leading trade contractors, like PNA, to understand and promote sustainable construction materials, product packaging, other innovations identified to reduce carbon, water, and waste in our industry.

While the industry has already seen these sustainability practices adopted in overseas markets like Europe, Turner and PNA are excited for the growth in sustainable construction in North America. "At Permasteelisa, we are pioneering innovations in curtain wall systems with a strong focus on sustainability. By utilizing aluminum sourced from clean grids and with high recycled content up to 85% and by integrating timber in some of our unitized systems, we are significantly reducing the environmental impact of our projects. In addition, our dedicated R&D initiatives are continuously exploring the next generation of innovative materials to develop low carbon and high-performance curtain walls. We are excited about these advancements and the positive contributions they will make towards creating a more sustainable built environment." says Zani.

“In order to see these changes come to fruition in our buildings, we have to gain alignment between the client, designers, and contractors so that our bidding documents contain the specified products that lead to lower embodied carbon targets. The technologies to push us toward lower carbon are developed. We need to get the bidding community to be encouraged, or better required, to implement these innovations,” advises Chris Parker, West Coast Procurement Manager for Turner. “We are grateful for Permasteelisa’s endeavors to go above and beyond in producing this EPD and striving for better-than-baseline results. However, hoping for the generosity and kindness of our trade contracting businesses is not a long-term strategy to achieve our aggressive and audacious goals. To reach net zero, it will take each player in our industry, working together to accomplish this common objective.”