Empowering Architects to Reduce Carbon Emissions

Within the past year, a number of architecture firms and allied organizations have formally declared a climate emergency and pledged to take action. But what should this action involve, and how likely is it to happen at the scale and speed required to prevent the worst outcomes of global warming? In this interview series, the League presents different perspectives on where architecture currently stands with regard to climate action, where it needs to go, and how it might get there.

How invested is the architectural community in preventing the worst impacts of climate change, and what barriers stand in the way of achieving this goal? Do architects have the information they need to decarbonize their projects? The League’s Sarah Wesseler asked KieranTimberlake principal Stephanie Carlisle, a designer and environmental researcher whose projects have included the Consortium for Building Energy Innovation and the Tally life cycle assessment tool, for her perspective.

Do you think architects generally care about climate change? Is it a priority for the people you interact with? And if so, do you think they have agency to do something about it?

I have no doubt that architects care a great deal. I hear a huge amount of concern from everyone from first-year architecture students all the way up to CEOs running some of the biggest AEC firms in North America.

There’s also a growing acknowledgement that architecture has a huge role to play in the problem. The built environment is directly responsible for 40% of global carbon emissions. That means we have a huge amount of agency. We make design decisions on our projects that directly affect climate change.

But an awful lot of architects and engineers are still having trouble connecting their own concern over climate with the day-to-day realities of practicing architecture. I think we can close that gap, but we’re not going to make any real progress unless we collectively focus our attention on how to make radical cuts in the carbon emissions associated with the built environment.

Where do you think we stand in terms of understanding how to do this? What do you see as the main challenges that need to be overcome?

I think one thing keeping us from making real progress is that too many designers are looking for either a one-size-fits-all solution or for a way to tinker around the edges to make buildings a little better-performing, like adding some insulation or using a bit less glass. But there’s no perfect solution that will work for every project, and, on the opposite end of the spectrum, we can’t solve the problem just by decreasing the carbon footprint of our buildings a little bit. We need to cut global emissions in half in 10 years.

We need a robust suite of tools and strategies to radically decarbonize construction across all our projects, not just the fancy projects or the unique projects. Our discipline really needs to take that research and education and innovation challenge seriously. There need to be strategies and workflows that work for every practitioner.

I also think we need to focus on building carbon literacy across every step of design education and practice. It needs to be a focus from the earliest years of school all the way to how firm leadership thinks about meeting the needs of our clients.

Another issue is that there really are no mechanisms in North America for a practitioner to be held accountable for the embodied carbon of their project. To me this is remarkable, mainly because we are incredibly responsible as a profession in terms of thinking about ethical practice. I don’t ever hear architects say, “Oh, I care about public health and safety, but not for this project. We’re not going to do any fire egress on this project, but maybe if there was a bigger budget we would.” But we say that all the time when we’re talking about design decisions that could protect the planet, which public health ultimately depends on. It’s really strange and perverse.

Back to your first question, I think architects have a strange relationship to power. We think we have none because we are in a service industry. And we are, indeed, working within the confines of contracts and projects and clients—that’s very real. But we also have this incredible power both to design cities and to shape ideas about how people can live. Somehow, we sort of oscillate between the two roles, having a sense of this important cultural responsibility, but also saying, “Oh, I can’t really do anything about this problem.”

I think that really weighs on people. I’m very passionate about the need to be more inclusive in terms of who feels empowered to address carbon on their projects. We need a lot of skill-building and education to really bring every architect and engineer into this movement.

You’ve done a lot of work on embodied carbon. Can you talk about why you’ve decided to focus on this issue, and how you see it playing out within the field at large?

There’s a huge growth in interest on the topic, which is incredibly important. It’s a significant percentage of emissions, but it’s also literally what we do—we make the decisions that determine the amount of embodied carbon, and upfront carbon specifically, which is the carbon emissions that are expended before the building even opens. All those emissions associated with the extraction, manufacturing, processing, and construction processes of materials—they’re what’s in our core scope of work. Those are the specifications we write; those are the drawings we make. Building materials are fully in our purview.

It comes back to the idea that the work architects and engineers do really matters for climate change. To be perfectly honest, in the past I sometimes felt like in order to make a difference I would be better off leaving architecture. A lot of my friends have had that feeling. You think, “Oh, I want to make a difference, so maybe I should go into policy, or maybe I should be doing community organizing, because it feels like I’m not making any progress here.”

This is super troubling. We need to talk more about the fact that we have incredible opportunities to tackle this issue as architects.

Tell me about Tally and how it relates to other embodied carbon tools that have been developed.  

When I entered practice about nine years ago, some methods of carbon calculation existed—namely life cycle assessment (LCA)—but they weren’t really being used in architecture. There were some tools out there; a very small community of people had been doing that work for a long time. But they really weren’t made for architects and engineers, and they didn’t necessarily fit very well into a design workflow. There were academics who would do very interesting studies after the fact, or using case study buildings, but if you were a designer and you wanted to understand the environmental impacts of design decisions, especially on complex projects, it was very difficult for you to get that kind of feedback. We need that information in real time when we’re making design decisions, the same way we do with cost and aesthetics and other types of performance.

So at KieranTimberlake, when we started taking on this issue internally, we realized we needed to develop tools that fit within the design workflow. We spent two years developing what became Tally, which is a plugin for Revit that allows architects and engineers to calculate embodied carbon, along with a full suite of environmental impacts. We built partnerships with Autodesk and with thinkstep, a leader in LCA data, in order to assure the tool was accurate, up to date, and easy to use. We beta tested the tool with architecture and engineering firms from all over the country who helped us understand how an LCA tool could fit into their design process. Since the tool was publicly launched seven years ago, any architect or engineer can use it to evaluate embodied and operational carbon impacts of their design projects in real time.

More and more tools are coming online that are doing the same for other workflows. That’s really important, because architects use different software and different methods of designing buildings. One tool isn’t going to work for everyone. The carbon community needs to support all those design methods.

The community of folks who are using those tools has grown enormously, especially in the last two years. These tools are also being taught in architecture schools all over the world. But it’s taking longer for folks in practice to really integrate the data and the analysis into their design process and see real results on projects.

So people are teaching it now, but it’s kind of trickling into use on projects—is that fair to say?

Well, there’s a lot more going on than that. In the last two years, the interest in embodied carbon has gone from a slow drip to the faucet being fully on. Five or six years ago, when I would go to LCA trainings or carbon-focused events, the same 20 people were always there. Now those events are selling out immediately, and we’re seeing interest from a much more diverse range of firms.

Some designers are now getting this training within their firms, and others are going outside of their offices because they want to be leaders within their own practices. I think that explains the really rapid rise of groups like the Embodied Carbon Network, the Carbon Leadership Forum, and AIA 2030. Folks are coming together to form community and to share data, strategies, case studies, and say, “You know, this is an issue that we should all be tackling collectively. I can’t do this by myself.”

Thinking about the issue of research more broadly, where do you see the main gaps in knowledge that still need to be filled in order for architects to take action on climate? And what do you see as the most effective ways for sharing this kind of knowledge within the design field?

There’s a lot of momentum building across the design community in terms of research and innovation on low-carbon building design strategies. Unfortunately, I constantly hear from academics and practitioners alike that no one’s doing work on this topic, which is not true. We really have a challenge in communicating across our profession. I think sharing information has long been a struggle for architects and engineers.

So many of the firms that have invested heavily in embodied carbon research on projects, or in developing tools, are doing an enormous amount of that work out of their own pockets. They’re doing it out of sheer alarm at the severity of the climate crisis, and also for the benefit of the discipline. There’s shockingly little support for research in practice from government, from academic institutions, from our professional organizations, from individual clients, from nonprofits. It’s just a real challenge in the US.

But even though there’s a scarcity of financial support, practitioners could make a lot of progress if we did a better job of building the infrastructure necessary to share data and research. Research on climate change should not be anyone’s intellectual property. It’s not something to keep within your firm. We’re in an all-hands-on-deck moment.

The shortage of large, rigorous studies, combined with the real sense of urgency to act immediately, leaves practitioners trying to use intuition based on older sustainability paradigms. But intuition is only good if it’s grounded in scientific nuance, research, and modeling, and that’s a really distinct project.

So I’m thinking a lot right now about how we do that work collectively. Groups like the Carbon Leadership Forum that bring academics and practitioners across disciplines together are well poised to lead that work.

At the moment, I’m not so interested in debating what the perfect solution is, or the right technology, or which one’s the most market viable. I think we need a broad toolbox of strategies that practitioners can choose from, and ways to help people really understand the efficacy of each strategy in different situations.

Are you aware of any models either within architecture or outside the field that start to point to what this could look like? My mind automatically jumps to a cross between Drawdown and LEED, but I’m sure there are better parallels.

The two big arenas where you find examples are in the world of technical guidance—you know, “Here are the strategies, here’s what you can do, here’s how they make a difference”—and regulation.

Of course, right now we don’t have strong carbon regulation in the US, aside from energy production. We’re starting to see more holistic carbon tracking and regulation in countries like Germany, France, and even Australia. I think a lot of progress will happen in the next few years in China, where folks are really transitioning towards saying, “We need carbon code, not just energy code.”

Within architecture, I think the best example, actually, is how we’ve made progress on thinking about energy performance for code compliance. Although I’m always pointing out that carbon and energy efficiency are really different, I think that’s actually the closest example, both historically and technically. Now, if you’re going to make something required by law, then there needs to be a pathway that is accessible and feasible for all practitioners and projects. There are essentially two approaches: a prescriptive pathway and a performance-based pathway. The prescriptive approach involves a set of rules you need to follow, like meeting a minimum insulation value in your walls, or a specific window-to-wall ratio target. If you follow these rules, then your project is compliant.

There’s also the performance-based pathway, which asks a team to make project-specific energy models, which opens up a range of strategies and innovation. This approach is far more technical and accurate, but it’s also not feasible or necessary on every project.

Right now, we don’t have a prescriptive pathway for understanding carbon—we’re just asking everyone to build nuanced and complex models and do the benchmarking themselves. We need both pathways for carbon, but if we provide strategies or benchmarks, they need to be based on research and models and real data. We can’t just wing it and hope for the best.

Are there any other messages you think are really critical to get across with regard to these issues?

One of the issues I think about most is how to empower all architects to address carbon on their projects. Even using the phrase “climate crisis” can be overwhelming, and most architects are not particularly eager to talk about politics or radical transformation. It’s just not in our culture. But I think it’s important for folks to realize that more gradual methods may have worked if we had started this decades ago—but we didn’t. There’s so much more that we could be doing right now.

But hitting the right tone is challenging. We don’t want to freak people out, but we’ve also all got to get more comfortable with some of these hard truths and look more critically at how we build and what we build.

I think a lot of that work has to happen internally at firms. Each office needs to figure out the right way to integrate low-carbon design into its design culture, because it’s not a one-size-fits-all solution. Firms need to demonstrate that leadership to their staff, and the designers who are the most excited about taking this topic on need to feel supported in doing this work.

We need to believe that this isn’t a trend or a marketing strategy. Climate change, along with equity, is the defining challenge of our generation.