by Dirk Kestner
Principal – Director of Sustainable Design at Walter P Moore
Twenty years ago, when I started my career as a Graduate Engineer at Walter P Moore, I had just completed research on the implications of recycling crushed concrete as aggregate in new concrete. During graduate school I developed some awareness of the environmental impacts of construction materials through Pliny Fisk III’s concept of Carbon Dioxide Intensity Ratios.
However, once in practice I found clients to be far more interested in the operational aspects of sustainable buildings, and was asked more than once “why are you here” when I introduced myself as a structural engineer at a sustainability event. Fortunately, there is now an increasing awareness of the importance of embodied carbon, but there is still much to be done to achieve widespread transformative reductions in embodied carbon.
Walter P Moore, an international engineering firm, embraces the challenges of achieving embodied carbon reductions and has sponsored the Carbon Leadership Forum since 2014. While our journey of addressing embodied carbon began by coupling material quantity takeoffs by Pliny Fisk’s carbon intensity ratios, we have advanced to incorporating Whole Building Lifecycle Analysis (WBLCA) as part of our design process and incorporating embodied carbon calculations into our in-house design tools and digital platform to allow our design teams to have a real-time understanding of the embodied carbon decisions they are making during design.
In 2012, with LEED v4 still in the Beta test process, Skanska USA Commercial Development challenged the Gensler-led Bank of America Tower design team to achieve LEED Platinum. This required our design team to not only lead the process of assessing the embodied carbon of the project’s structure and enclosure, but also develop design schemes to achieve reductions. This challenge was our first large project to address embodied carbon. It led us to a deeper understanding of both how our design and specification processes can be optimized, but also that realizing true reductions to embodied carbon requires a collaborative approach including both the design and the construction team.
Helping to Drive Transparency
This experience, highlighting not only the importance of design level optimization, but also the need for supplier specific embodied carbon data, was a driving force for Walter P Moore to become a Pilot Sponsor of the Embodied Carbon in Construction Calculator (EC3). EC3 makes Environmental Product Declarations (EPDs) easily accessible and digestible to members of the design and construction community, which in turn, highlights differences in the embodied carbon of materials that might otherwise be functionally equivalent.
We are currently building upon the lessons learned from Bank of America with Skanska’s newest office tower in Houston, 1550 on the Green, designed by BIG in collaboration with Kendall Heaton, where we are collaborating with Skanska to encourage local ready-mix suppliers to develop concrete mix specific EPDs. This will allow the expanded use of EC3 and enable more specific procurement requirements for future Houston projects.
Education and Advocacy
In November 2020, Walter P Moore issued Embodied Carbon, A Clearer View of Carbon Emissions, which outlined our initial journey addressing embodied carbon, as well as stories of our initial project applications. Our approach to addressing embodied carbon is to educate across our organization. For example, during the last five years we have included a module on sustainable design and embodied carbon in our firmwide FastStart employee orientation program. Our employees have responded by taking founding roles in the teams establishing CLF local HUB’s in cities across the country including Atlanta, Austin, Los Angeles, and most recently Dallas.
While we are focused on our internal processes and teams to achieve embodied carbon reductions for the projects we design, we understand that industry collaboration, with not only our clients, but also with our peers, is essential to achieving transformative reductions in embodied carbon. This is one of our motivators for being both an inaugural signatory as well as a member of the Structural Engineers 2050 Commitment (SE 2050) leadership committee. SE 2050, and specifically creating our annual Embodied Carbon Action Plan allows us to articulate our commitment as well as outline the specific steps we are taking in the areas of education, reporting, reduction, and advocacy.
Furthermore, we recently became a signatory firm in Architecture 2030’s COP26 Communique. The communique will be sent to the world’s governments from signatories responsible for planning, designing, and constructing a major portion of the global built environment. The goal is to have governments ramp up their Nationally Determined Contributions—national government climate plans that include emissions reductions targets for 2030 and beyond.
While many of our initial experiences addressing embodied carbon centered around our structural engineering practice, we are currently applying our lessons learned to our other practice areas. Specifically, these include enclosure design, stewardship of existing buildings, and horizontal infrastructure. Each of these areas has potential for embracing embodied carbon reductions.
Enclosure design offers the opportunity to achieve embodied carbon reductions in high impact per mass materials such as glass, aluminum, and insulation while maintaining operational carbon efficiencies. Stewards of existing buildings have the unique opportunity to quantify the existing embodied carbon of a structure, and to educate an owner of the tradeoffs of saving a building. Finally, horizontal infrastructure and site development offers new opportunities to expand the embodied carbon dialogue to typologies currently not as frequently involved in the embodied carbon discussion. These structures, including pavements, bridges, and dams can use large amounts of material, and are often times governed by organizational level specifications and design criteria, which allows for the opportunity for changes to one specification to influence multiple projects.
Dirk Kestner, PE, SE, LEED AP BD+C, ENV SP, is a Principal and Corporate Director of Sustainable Design at Walter P Moore. He can be reached at firstname.lastname@example.org.