Updated: May 13
Interviewed by Yingying Zhu
Interviewed on February 10, 2020
Cara is an Associate Director on the Buildings team at Sidewalk Labs, the urban innovation arm of Alphabet (Google). Cara has acted as the PM of Sidewalk’s R&D on mass timber buildings, including an effort to design a 35-story mass timber tower, which was recently featured in Business Insider. Prior to Sidewalk, Cara worked for ReD Associates, a Danish innovation consultancy, where she helped develop LEGO's five-year innovation plan, among other projects. In 2014, she took a sabbatical from work to conduct research and write about the post-war redevelopment of Sarajevo as a National Geographic Explorer. Cara is a native New Yorker with a degree from Princeton, where she focused on urban policy, planning, and architecture. Cara is currently participating in Coro Leadership New York, an urban leadership development program.
You wrote a three-part blog  series about Sidewalk Lab’s R&D efforts in mass timber construction. Can you walk us through why mass timber is a better alternative to concrete and steel? Mass timber comes with three different advantages. Environmental – Trees sequester carbon whereas steel and concrete generate carbon when being manufactured. A couple of studies have shown that timber can have over a 25% reduction in embodied carbon, if the timber is harvested the right way. Construction timeline and cost – Production of timber buildings in a factory followed by shipment to site will save time and cost, similar to the benefits that you would see from modular construction. In addition, timber is naturally easy to work with in a factory, as it can be cut and does not require custom molds for each piece. User experience – A good number of studies has shown that biophilic design and exposure to natural material has effects like increasing productivity, lowering depression, improving educational outcomes and helping patients heal faster.
“In 2021, the IBC is set to go up to 18 stories for mass timber buildings which should help boost people’s confidence and push the market along.”
What’s the existing market for mass timber construction? Among the tallest buildings are an 18-story mass timber building in Vancouver, Canada, an 18-story building outside of Olso, Norway and a 25-story tower called Ascent that was just approved and is about to break ground in Milwaukee, Wisconsin. The movement is largely driven by areas that have large forestry sectors such as Washington and Oregon in the U.S. and British Columbia in Canada. New York, where I live, is not always the first mover when it comes to new construction technologies but there are at least four mass timber buildings (all 5-stories or shorter) in Brooklyn right now that are completed or nearing completion.  These early examples show more developers have come to understand the three-pronged benefits of the technology.
Right, I heard the CEO of Taconic is very enthusiastic about this technology too. Is building code the main hurdle for mass timber to become more prevalent? It’s one of the hurdles, but that’s starting to change. In the U.S., the International Building Code (IBC) sets national standards and then individual jurisdictions, such as the NYC Department of Buildings, have to choose to adopt those standards. In 2021, the IBC is set to go up to 18 stories for mass timber buildings, which should help boost people’s confidence and push the market along. Across the world, more progressive legislation is coming out in favor of timber. For example, France announced in February that, on all of their public buildings, including those for the Paris Summer Olympics, at least 50% of the material has to be wood or other bio-based material, starting in 2022.
What is the status of Sidewalk Labs’ mass timber project? My team at Sidewalk Labs has focused on developing a digital prototype of a representative 35-story mass timber building, which we have used to sort through the relevant design, engineering, manufacturing, regulatory, and financial issues. This prototype, which we call Proto-Model X (PMX), could apply to any location —it is site agnostic. We modeled the building in BIM (Building Information Model) 360, and have been running tests on its hypothetical performance and manufacturability. We work with a team of world class mass timber experts including Michael Green, Gensler, Aspect, Atelier Ten and many others. This is an iterative process–the digital parts are constantly being redesigned and optimized in response to new input on the design, the structural solution, the façade, the MEP system, and more.
“We don’t think anyone is currently taking advantage of the full potential of timber integrated with modular construction and digital manufacturing. This ultimately will allow developers to build much more efficiently, and it’s where we have focused our own R&D.”
How different are Sidewalk’s buildings from other existing products? Sidewalk has had the good fortune of having two years of master planning, during which we could work on R&D. We have had time to invest in developing a full library of parts including floor cassettes, walls, facades, structural members, and other pieces. The challenge is in optimizing the factory economics by standardizing some portion of the pieces, while maintaining the design quality and user experience. When it comes to manufacturability, which is crucial, we have been working hard to drive three things down: the total number of pieces used on the project, the total number of unique, custom pieces, and the time and complexity involved in producing each piece. We are learning from a few factories in Switzerland, Germany and Austria, who have extensive experience building with mass timber. But we don’t think anyone is currently taking advantage of the full potential of timber integrated with modular construction and digital manufacturing. This ultimately will allow developers to build much more efficiently, and it’s where we have focused our own R&D.
What is the next step for PMX? We have published the initial findings for the 35-story prototypical building and are now working through a full family of prototypical buildings that we can use to test the kit of parts, and explore different building heights and circumstances. At the same time, we are working with a full supply and manufacturing team on planning a factory in North America to make these prototypical buildings a reality.
Sidewalk Labs is experimenting with many new construction and real estate technologies beyond timber, like modular construction and flexible walls for retail and residential spaces. What is the overarching theme behind these innovations? This is a complicated topic. We typically look at three main things during our R&D: the cost vs. value added, the technical feasibility, and the improvement to the user experience that the technology can bring. If these three things check out, we would then choose to either partner with an existing technology provider, or incubate the idea internally. For example, we invested in a digital electricity start-up called VoltServer, and we use their technology throughout our planned buildings to create flexibility in our walls.
Are you aware of any other alternative materials to concrete and steel? There is lots of research being conducted around cement replacement. People are replacing cement with fly ash, slag or other byproducts. These byproducts are arguably more environmentally friendly than using more cement, which is a major contributor to global carbon emissions.
What other construction technology or urban technology ideas excite you? One thing I am really excited about are platforms that allow people to invest in their own neighborhood through shared ownership. For example, Neighborhood Investment Company (https://mynico.com/) based in Echo Park, L.A., is a neighborhood REIT that makes it possible for people who love Echo Park to build a financial stake in their community by investing in local real estate at a minimum of $100. It is an interesting and creative way to give local residents an opportunity to share in the wealth that is created as their community improves.
Can you talk about your early career working for a design consulting firm in Copenhagen? I worked for a consulting firm called ReD Associates, who do design-thinking consulting and help companies develop products and set long term strategy. I worked on a number of urban focused projects, including ones for a building parts manufacturer, as an example. I also got to work with clients like LEGO, which is shockingly relevant to the modular timber building design that I am doing now. It's actually a very similar concept. When you're designing a LEGO set, you're trying to figure out how to keep down the number of custom pieces that are used, while still ensuring it's a cool, new, interesting experience for the (little) people who will play with the product. I did a lot of qualitative user research for that purpose, such as in-home ethnographic research, which is something we also try to do a lot of at Sidewalk.
How did you get into urban development and Sidewalk Labs specifically? When I applied to Sidewalk, I had a managerial background, with a specialty in planning and architecture, which I had studied. My pitch was that I knew how to manage complex strategy projects and how to research and develop physical products, which is a lot of what Sidewalk does. But it was also a lesson in persistence: I emailed them for a year before they decided to hire me. At Sidewalk, I have been very lucky to have a number of great mentors who have sponsored me and given me the flexibility to switch into the areas that I am interested in, where the company also needs support.
What skills are instrumental to your current role? My role is essentially a product manager orchestrating 10+ consultants, who each speak their own languages and specialize in their own fields. I need to bring everyone together and make sure we, as a team, are running in the same direction and deliver results. I think what makes a great manager of a complex project is appreciating people for their respective specialties, drawing out what people are best at. For example, a general contractor’s specialty is to check for constructability and to make sure their pre-construction cost estimate is accurate, so I will let them focus on that. Setting up trackable qualitative and quantitative benchmarks is essential and my previous consulting skills comes in handy here to identify the right metrics. Making connections in the broader mass timber industry through conferences and events is also important because you need to know good people to pull in.
You were a National Geographic Explorer. What did you do for them and what did you learn from that experience? A lot of people don’t realize that National Geographic has this amazing program, where if you propose a smart idea for a project in one of their focus fields (including urban geography!), they will fund it. I proposed an idea based on my prior research about the geopolitics of city planning in Eastern Europe. I wanted to go to Sarajevo, Bosnia, where I had spent time earlier in my life. National Geographic liked the idea and sent a photographer with me. I spent time interviewing developers, architects, planners, and people in government, and wrote a blog series about how urban planning and architecture have both helped and hurt Bosnia’s post-war reconciliation process and reformation of their national identity.
What other side projects do you do? I participate in an urban leadership development program called Coro Leadership New York (LNY). The group is split across members from the public sector, private sector, and non-profits. It’s about 50 people, and we meet periodically to discuss some of the biggest urban policy issues that the city is facing. You are assigned to a sub team of 5 or so, and you have to curate a day’s worth of content for the rest of the group on a particular topic, such as how the city responds to 911 calls or how the city should regulate urban freight deliveries. We did a very educational day on bail reform legislation recently, where we heard from the Brooklyn District Attorney in the morning, the Manhattan District Attorney’s office in the afternoon, criminal justice advocates later in the day, all in addition to observing the actual arraignment process. It is a very cool program through which a diversified group of mid-career civic professionals learn how to make the city better, on a series of super varied but important subjects.
Edited and condensed for clarity.
 Link to Cara’s blog about mass timber construction: https://medium.com/sidewalk-talk/introducing-pmx-our-model-for-how-tall-timber-buildings-could-work-in-cities-4402fab7ac45  Namely 320 and 360 Wythe Ave, 82 Ainslie St and 283 Greene Ave.