Bill Baker is one of the world’s leading structural engineers. He has designed innovative structures that range in scale from single-family homes and small pedestrian bridges to the world’s tallest manmade structure, the Burj Khalifa in Dubai. His cutting-edge designs include the unique Broadgate Exchange House in London—which is both a building and a bridge that spans over Liverpool Street Station—and the cable structure entry pavilion for the General Motors Headquarters in Detroit. Additionally, Bill is widely recognized for his collaborations with renowned artists, such as James Carpenter, Janet Echelman, Iñigo Manglano-Ovalle, James Turrell, and Jaume Plensa.
“Structural innovations move architecture forward. They create new design opportunities that can lead to new architecture. The designs of many of our most famous buildings are based on structural innovations.”
Many of Bill’s structural innovations are a result of his extensive research in structural systems, which he shares through his teaching, lectures, and numerous publications. He is an Emeritus Honorary Professor at the University of Cambridge and has also taught at MIT, the University of Illinois at Urbana-Champaign, Illinois Institute of Technology, Northwestern University, and Princeton University.
Bill has received honorary doctorates from the University of Stuttgart, Heriot-Watt University, the Illinois Institute of Technology, and the University of Missouri. He has been honored with the Gold Medal from the Institution of Structural Engineers (IStructE); the American Society of Civil Engineers (ASCE) OPEL Lifetime Award for Design; the Gustav Magnel Gold Medal from the University of Ghent; the Fazlur Rahman Khan Medal from the Council on Tall Buildings and Urban Habitat; the Fritz Leonhardt Preis and the Torroja Medal from the IASS.
Could you share some information about your personal and professional background, as well as what motivated you to pursue a career in structural engineering?
I grew up in a small town in Missouri and always enjoyed studying math, science, and history. When I was in high school, I took an aptitude test that suggested I might want to be an engineer, and at that time, I “didn’t” know what an engineer was. When I asked my mother about it, she said that my grandfathers had been engineers, although they had already passed away long before I was born. As I looked into various engineering fields, I thought creating something as substantial as a bridge would be interesting, and I ultimately chose to pursue structural engineering. It was only later that I discovered that both of my grandfathers had pursued careers as structural engineers.
Can you share your experience of the initial years you spent at SOM, and discuss the state of structural engineering leadership during that period?
When I joined, SOM was certainly a robust practice, with engineers in many offices—Chicago, New York, Houston, Denver, and San Francisco, to name a few. At that time, the firm had recently completed the Hancock Tower and the Sears Tower, and was almost finished with the Hajj Terminal, so there were very remarkable structures coming out of SOM at the time.
As a junior engineer, I worked on a supertall project under Fazlur Khan before he passed, and I developed concepts that I later published in an article. I also worked with Senior Engineers John Zils and Stan Korista, and on various projects and papers with Hal Iyengar, who was the senior partner after Faz passed away. In the 1980s, I assisted Hal when he served as chair of the Structures Congress in Chicago; when the organization returned to Chicago several years later, I served as chair.
Can you share your journey as a pioneer in designing tall buildings, starting from your initial involvement in a high-rise project to your most recent work?
Many contemporary tall building technologies of that era were invented by SOM working with architectural students at the Illinois Institute of Technology (IIT). At the time, SOM partners Myron Goldsmith and Fazlur Khan were teaching at IIT and were coming up with ideas about structure that would lead to new architecture. When Faz died, I and others stepped in to help and started working with graduate students.
As a junior engineer, I spent a lot of my workday doing as I was told in the office, while on the weekends, I worked with Masters’ students on their thesis projects. They would always ask me what felt like rudimentary questions about why things were done in a certain way, which forced me to think hard about my answers and reflect on my professional work.
Back at the office, when new projects would come in, a friend and I would guess what the structural system might be before it was chosen. We would then compare them with the direction set by the leadership—sometimes we thought ours were better, and other times ours were not as good. I worked on several projects under John and Stan, one of which included a slender 27-story building in Chicago, which taught me a lot about the stability and design of tall buildings as well.
The more experience you have, the more ideas you can generate for the next project. This experience can be from past projects, research, conferences, discussions, and studying the work of others.
The Hancock Center and Willis Tower achieved incredible heights with remarkable material efficiency at a time when no one talked about sustainability. Tell us, how did this inform your designs?
A lot of SOM’s hallmark work is largely driven by efficiency, which has always been central to the firm’s philosophy. This, of course, was very influential in the work of Myron and Faz, who were always looking for systems that were as efficient as reasonably possible—for economic and philosophical reasons. Back then, sustainability wasn’t spoken of as much as now, but efficiency has always been inherent in what we do.
Many of the greatest stories of innovation are primarily driven by the goal of the economy, not just in tall buildings but also long-span structures or bridges. Much like in nature, efficiency drives innovation in the creation of new systems.
How does the structural design of buildings classified as “super-tall towers” differ from those that are typically categorized as “mid-rise”? Is it appropriate to compare structures such as the Hancock Center, 100 Mount Street, or 800 Fulton Market? What are the shared and distinctive structural features of these buildings?
One of the things that Myron Goldsmith did in his Master’s thesis with Mies van der Rohe was draw a series of bridges of different lengths, demonstrating the different systems required for each of the spans. For plants and animals, different species also work at different scales. In the same way, while low-rise, mid-rise, and high-rise buildings all resist forces like gravity and lateral loads, in reality, the scale of the problem changes dramatically. The program of the building also affects the system—whether it’s office, residential, or mixed-use—each of these typologies come with different constraints that ultimately fuel the creative process.
Among many other examples, the Hancock Tower is a product of its constraints with its diagonal braces that are both aesthetic and functional. How would you do that with concrete? There have been various experiments in New York and Chicago where you take a concrete tube and fill the windows with concrete to create diagonal bracing. 100 Mount St. and 800 Fulton Market take a different approach—they’re both fundamentally concrete buildings braced with steel. Historically, there’s a reason that this was not achieved in this way, and we’ve studied those issues and have been able to address them. We have not only demonstrated that it can be done but also that it can be done efficiently.
Can you provide a brief overview of the research projects that you have spearheaded at SOM, and how the insights gleaned from these studies influenced your design approaches?
As I mentioned, in the 1960s, Myron and Faz led a lot of the research at IIT, and many of the systems we use today were invented and developed by SOM during this era. Research has, in many ways, been integral to the firm’s culture ever since. The big difference is that eventually, it moved in-house—sometimes both in formal or informal capacities.
A few years back, we had two parallel organizations. One was archi-tecturally focused, called the “Black Box” group for computational design. The name was ironic, as it was all about opening the black box! The other, I would call the research gang, which was a casual structural engineering-focused group.
Now we have an official practice called Research and Innovation (R+I), which is cross-disciplinary, tackling everything from structural ideas to furniture design, lighting, and beyond.
As a multidisciplinary firm, what distinguishes SOM’s process from others, and how has it influenced the successful construction of numerous tall buildings around the world?
It’s not an accident that SOM has done such an enormous number of tall buildings worldwide. These are very technical problems, and I would say that SOM being an “AE Firm” with world-class architecture with a capital “A” and world-class engineering with a capital “E” enables us to do that. There are a lot of firms out there that have both disciplines, but few that place the same emphasis on each. Our architects and engineers also challenge each other to be the best and don’t accept less than that. Over many years, we have found many advantages to having such an integrated practice.
In what ways do you believe that your role as a mentor has influenced the development of the field of structural engineering within SOM? Additionally, with the recent appointment of Eric Long as a new structural engineering partner, how do you anticipate that the discipline will progress in the future?
The leadership of the structural group at SOM has evolved, and although there is much common ground, everyone has a different focus.
Mine was more on pure blue-sky research, where we would investigate interesting things that we didn’t know much about nor understand if they had a practical use. But I would say that almost 100% of the time, we found a practical application for knowledge we gained. One of the things that I’ve always enjoyed about SOM is that the research is done by designers actively working on projects, not a siloed group, which I think certainly helps.
Much of the work we’ve been doing is in seismic zones, and there has been a lot of fascinating research on the West Coast produced by people like Mark Sarkesian and Eric Long. Eric has led incredible tall building projects in Mexico and directed some creative work for the LACMA with Peter Zumthor. He is also leading his own research, which I find incredibly exciting.
In light of your many years of teaching experience, how has academia contributed to your career and your understanding of the profession?
A lot of what I know now I was never taught at school because my professors didn’t have the knowledge to share. One of the things we try to do at SOM is to share our knowledge and experiences. I remember hearing Fazlur Khan give a talk once at an engineering dinner, where he said that his goal was not to patent but to publish… and then to go on to the next idea before anyone else got there! He was certainly successful at that.
Now that we’re more focused on sustainable solutions, we know a lot that can make buildings significantly more efficient and enable other designers to find these systems more easily than they have been taught.
At SOM, we put considerable effort into publishing and teaching our work. It is said that if you think you understand something, try writing a paper about it, and you will usually find holes in your knowledge. If you really think you understand it, then try to teach it. In teaching students, we typically find that we teach ourselves and learn what we think we know in much greater depth.
We’ve had the opportunity to work with several brilliant students, some of whom we’ve hired. Many of them are doing things that I find remarkable.
Lastly, tell us about your favorite tall building and why?
Out of all the tall buildings that I had nothing to do with, the Hancock is my favorite. I like a lot of structures, but the Hancock is quite extraordinary. It’s so clear and effective. It’s truly an amazingly sophisticated solution at a time when the computational power was more limited. While it’s true that we know more now than we did then, I would say that it’s still hard to beat that one.