Despite my arriving twenty minutes early to Knippers Helbig’s office in New York’s financial district on a brisk Friday afternoon, I am warmly welcomed at the door by an engineer whose work I probably just interrupted. As he goes to summon a man around the corner, I peek at the office space: not enormous, but still spacious and pleasant, giving no sign of being too small for the number of engineers at work. Thorsten Helbig, principal of the Germany-based engineering firm Knippers Helbig (KH), emerges immediately, equally warm and welcoming as he ushers me into the office’s conference room. The room opens up on two sides to the office space, and Helbig goes to shut both doors; despite the auditory privacy, the work carried out in this room is always transparent: one wall of the conference is a glass window, allowing any passersby to glimpse at our meeting through the satisfyingly enormous letters “KH” staining the glass orange.
It is perhaps no coincidence that the office space articulates such clear architectural considerations. Helbig’s approach towards meshing engineering expertise with architects immediately becomes our first and most fruitful point of discussion. “In a relationship between engineer and architect, I think what is most important is that there is mutual respect and a communication,” Helbig asserts. “Ideally, the communication starts very early in the design process.” In many projects, he explains, Knippers Helbig is involved from the very beginning—ideally, at the competition stage—to the final completion and execution of the project. From the start, every decision made by the architects in organizing the program leads to consequences that require the engineers’ input regarding limitations such as soil conditions, column spacing, and slab systems. Inevitably, the engineers put forth decisions and recommendations that influence the project’s appearance, but Helbig underlines that “we as engineers should not try to be architects, but rather maintain an engineering perspective.” Projects can benefit so much more from an engineer’s engineering contribution, Helbig points out. “At the same time,” Helbig qualifies, “I expect that everybody at the table has a qualified opinion. As an engineer, we can question some of the architect’s decisions, which can—in the best case—make the architecture even better.” Helbig says that while there exists the notion of signature architects, he doesn’t believe in “signature engineering.” We can look at some buildings and often guess at the architect, but Helbig doesn’t find it “right” to be able to do the same with the engineers of building structures, even if the engineers’ contribution can be clearly read in many building types. “As an engineer, I want to be able to support architecture. We start with the same open-minded approach in every collaboration, but it consequently leads to different results when we work with Massimiliano Fuksas, Renzo Piano or Liz Diller because their individual architectural approaches require individual engineering solutions. I see us as collaborators in exploring the inherent potential of the architectural intention – and sometimes innovatively engineered parts act as catalysts for specific architectural expressions.”
Occasionally, Helbig admits, friction arises between the architect and engineer, particularly with form finding. “When you use the form finding process, the shape cannot be manipulated much, especially with tensile structures: you can’t influence the physics. We don’t see purely form-found architecture often since most architects want to set the form themselves rather than let physics dictate the form.” But these conflicting approaches are not impossible to resolve, as is demonstrated by KH’s Casa Shopping Carioca Wave–though form finding was not the exact technique initially used for this swooping steel-and-glass canopy, KH first used basic engineering principles to propose a structurally robust form, which was then passed between architect (Nir Sivan Architects) and engineer to make, respectively, aesthetic and structural adjustments as needed.
Collaboration and teamwork comes to strongly characterize Helbig’s discussion of the design process. “I see that our collaboration works best at the early stage when we all have a voice– when everyone is able to communicate in a way that helps the process. That’s an issue we have because in education, we engineers are not educated to communicate.” Helbig acknowledges the single profession of Baumeister, literally “building master,” which gradually diverged in the 19th century into today’s two very different professions of architects and engineers, noting that the education systems of the two fields have also diverged greatly. Architects, he explains, are “much more educated to present and to discuss”: students in architecture are much more accustomed to presenting their work, receiving feedback, responding to the feedback, and defending their ideas. On the other hand, “some engineering students graduate without having been in touch with an architect; some see an architect for the first time when they start practice.
“It’s not that we have to be fully educated in architecture,” Helbig says, “but curiosity in architecture helps. Above all, though, we as engineers have to be educated in how we communicate: how we deal and interact with another opinion, how we explain the consequences of design decisions, how we discuss with architects and other engineering disciplines, and lastly, how we convey to our clients why a specific solution works best.”
Helbig’s own background has undoubtedly shaped his approach. He recalls his time studying structural engineering in a small campus environment where friends in architecture teamed up with friends in structural engineering to work on projects (“lookout towers and bridges were the typical tasks for students”). Helbig also cites his seven years working at Jörg Schlaich’s office, sbp, in Stuttgart, Germany as formative in his early years as an engineer. “I learned a lot from Jörg Schlaich—not necessarily just about how to solve a detail, but about approaching the profession and understanding our contribution as engineers.”
The collaboration pervading Helbig’s design process is not limited to that with architecture. Asked about sustainability, Helbig returns to his design philosophy: as an engineer, “you have to be part of, and an influencer of, the whole process.” Sustainability, he says, needs to be holistically incorporated into the design process. From the perspective of minimizing material, a lightweight suspension bridge can often be considered a more sustainable solution than a massive timber bridge, but there are situations where this would not hold true. “There are contexts in which the suspension bridge would be inappropriate: poor soil conditions, for example, would necessitate soil anchors, and the production of soil anchors and high-strength steel cables can result in high carbon dioxide emissions. The timber bridge, on the other hand, would provide a long-term carbon dioxide storage.”
Though KH is based in Germany, Helbig comments that creating the New York office was first encouraged by German specialty steel and glass contractors who sought to facilitate project communication. Helbig soon found that New York features a “dense and interesting architectural scene—when I’m in the Stuttgart office, to meet the international architectural elite, I have to travel to the airport; in New York, to meet with those architects, I simply take the subway or walk around the corner.” The arrangement worked so well that they eventually established the permanent office in the Big Apple. “It’s funny,” Helbig laughs, “there are not many European engineers in the US, but there happen to be three structural engineers from Stuttgart in New York now– at one point in time our offices here were all within a few blocks of each other!”
So what sets KH apart? “Schlaich’s firm, sbp, is about thirty-five years old. Knippers Helbig is fifteen years old in April 2016. If sbp is an adult, we are a teenager.” Rather than focusing on specific construction or building types, Helbig explains, KH is interested in supporting interesting and ambitious architecture while embracing a variety of explorations and innovations along the way. He speaks about the continuous feedback between research and practice, particularly facilitated and supported by his partner Jan Knippers’s role as a full-time professor at the ITKE at the University of Stuttgart. As an example, he refers to ongoing work on a shading system at Harvard’s Allston Science and Engineering Complex (architect Stefan Behnisch). “We discovered that instead of using conventional sheet metal, we could use biodegradable polymers as a more sustainable approach, and that’s something Jan Knippers already worked on at the ITKE. We thus used this information and applied it to the project. In this way, the research gets more related to reality and is tested for its potential applications in the building industry.” It works both ways: in practice, Helbig says, “we run into certain architectural languages to explore in parallel with ITKE’s—for instance, kinetic structures have allowed us to explore bending-active mechanisms with ITKE.” With this approach, KH dives into a wide range of engineering solutions with the vibrant curiosity of a teenager.
To current students of structural engineering, Helbig’s advice is to “be and stay a teenager in our profession.” He advises students to “be curious and question given limits. You can find innovation by taking risks and looking beyond conventions of safety if your approach is based on a deep understanding of material performance and the latest technologies.”
I ask Helbig to comment on the future of the firm. Will KH eventually “become an adult” and settle for specializing in a particular area of structural engineering? Helbig’s response is as humble as he is throughout the interview, dismissing the notion that he has a “master plan” for KH—“ten years ago, I would never have imagined that we would come to the US.” He shrugs similarly at the question of KH’s future focus.
“I hope we can be a teenager forever,” he laughs. “That’s the dream, right?”
Knippers Helbig was established in 2001 by founding partners Jan Knippers and Thorsten Helbig, and was joined by Boris Peter in 2012. KH’s teams are located in Stuttgart, New York and Berlin.
Author: Demi Fang ’17