Exploring How Transportation Drives Sustainability in the Built Environment

Reshaping How We Live and Move: How Tall, Urban Towers and Suburban Communities Can Realize 1.5°C Ambitions is the latest Impact Fund report.

Our research examines the carbon emissions associated with built environments throughout their entire life cycles. It found that while 55-60% of emissions before 2030 were attributable to the embodied carbon of the materials, transportation emissions are substantial enough to surpass everything else in the long term. 

Lead researcher and author Jeremy Field, an associate in Introba's Vancouver office, discusses the significance of these findings, what they mean for the future of urban planning and building design, and the magic of making the sustainable choice the best one. 

Why did you decide to explore this idea? 

The World Green Building Council published a report (Beyond Buildings) in 2021, calling for buildings and infrastructure to be considered systemically instead of as standalone elements to achieve global sustainability ambitions.  

We asked ourselves: "Okay, but how can we actually do that?" 

Asking that question highlighted the need to think about not just each building we may be designing but also the built environment as a whole. Even if we have the same building, locating it downtown or in the middle of the wilderness will fundamentally change how people use it and how they get to and from there. 

It also highlighted the need to ask: are we making the optimal design decisions? How can we be sure If we aren't looking at the whole picture? The idea also came from a more personal place; I've lived in several places growing up. While living in settings like here in Vancouver, I often walk and cycle. At other points in my life, I've lived in more suburban settings, and although I didn't change, my daily travel habits did. I have experienced how different built environments influenced my lifestyle and transportation patterns. On the other hand, thanks to my role at Introba, I know that suburban housing generally needs much less concrete and steel than an urban tower. I wondered—in which place was I closer to living a zero-carbon lifestyle?  

To answer this question, we needed a framework to evaluate the whole-life carbon emissions of entire built environments. With that, we can ensure the next generation of sustainable neighborhoods is designed without blind spots—seizing every opportunity to drive down emissions and secure a stable climate. 

Did you encounter any challenges as you started to dig into everything? 

We had to make many choices around what data and assumptions to use, and there were so many iterations we could have done. We tried to choose the most reasonable and familiar ones, which led us to two forms of the built environment that are common in North America and recognizable globally—simply think of the setting of Friends or The Simpsons. In the report, we detail how we developed the methodology. It would be worth revisiting as new data becomes available or focusing on additional building typologies or on different continents.  

What are the implications of finding out that, over the long term, the emissions from transportation outweigh the carbon associated with the building materials and operations?  

This means that when individuals choose their next home, the walkable, cyclable, transit-friendly option is likely to be the most sustainable option—even if it wasn't built using the fanciest materials. 

On the owner side, for developers, cities, or other building owners, if you're looking to build a low or Zero Carbon building, you can't ignore locations with higher walk scores, bike scores, and transit scores. It also means that capital shouldn't be entirely allocated to window upgrades or low-carbon materials because improving a bike lane or funding a higher-quality bus stop may have a more significant impact. Especially since we now know that even if the building itself is designed to be net zero, it may matter just as much, if not more, how people get around. 

For professionals like architects, engineers, designers, and planners, the implications are that we can't be narrow-minded in our concerns. We must include elements that will make choosing sustainable mobility options more effortless for future residents—for example, at-grade bike rooms or EV charging stations. Additionally, measures like street-level retail can reduce carbon because they provide amenities people can walk to. Overall, we need to pay more attention to how we can contribute to increasing the availability, accessibility, and resiliency of multiple modes of travel.  

How will this knowledge help you solve client challenges? 

Clients only have so many dollars; they trust us to help them allocate them. I want to help them achieve the highest impact use for those dollars, and now we have better knowledge to help them do that. For clients with zero-emissions goals, this way of thinking at the built environment scale brings new and familiar strategies back for consideration, giving them more options — meaning additional flexibility, which is never unwelcome during design.  

What are the key takeaways from this research? 

When investing in housing, the choice of location and type of development is crucial. It affects the initial burst of embodied emissions and shapes the daily lives of hundreds of people, collectively contributing significantly to the overall carbon footprint.  

How we've been overbuilding car-centric infrastructure has created built environments that, in some cases, we don't even love. We end up with more car accidents and time spent dealing with insurance, which all contribute to a lower quality of life—but modifying our built form could help put us on the path to a better life. 

Where do you hope we can go from here? How can we build on and apply this knowledge? 

I would love to start building on this and integrate it into the current strategies we consider when trying to make a building more sustainable. For example, if we use a life cycle assessment to evaluate the materials and the energy model, how do we layer transportation as a lever to manipulate values, and how does the net balance shift? One of the results we found is that while there is a quantified difference between suburban and urban vehicle miles traveled, there are also differences in mode shift or mode share—for example, driving percentage versus transit use versus walking. And mode shifting. 

Most of all, I would love to see this show up in district planning exercises—a scenario where a city could set specific sustainability outcomes and objectives and leave flexibility for developers, architects, and engineers to exercise creativity in reducing emissions across entire neighborhoods.  

The question we need to ask and answer at scale is, how can we help future residents live the lowest-impact lives possible without requiring them to think about it? That's the magical part. To make it easy and seamless, if we can design built environments that position the low-carbon option as the convenient option, generations of residents will be successful at living sustainably because it's baked right into the space.  

Read Reshaping How We Live and Move: How Tall, Urban Towers and Suburban Communities Can Realize 1.5°C Ambitions here.

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About Impact Fund 

Introba's Impact Fund is an initiative to create a positive global impact on the built environment through investing in transformational research in sustainability and digital innovation. By sharing our findings and insights, we help grow our collective knowledge and catalyze action.