When I visited Christoph Ingenhoven’s 1 Bligh Street in central Sydney shortly after it was completed in 2011, it gave me chills: “What holds all this glass together?” I wondered. You enter the full-height atrium from beneath the uplifted building, take a glass elevator to reach the public roof garden, and all that time your vision is entirely unobstructed — you see the street, the offices inside, the sky overhead, and the harbourfront skyline. There is structure, to be sure, but when you don’t see it head-on, you start to believe it doesn’t exist. Light and sleek, the building is inviting; and despite drawing attention to itself, it works perfectly well with its surroundings, a tight intersection of bulky, mostly stone-clad buildings.
Born in 1960, Ingenhoven grew up in Düsseldorf, Germany, where his father had a small architecture practice. Ingenhoven recalls that much of his adolescence was spent between the tennis court and his father’s office, where he worked as a draftsman on and off. It would have been natural for father and son to go into partnership. But upon graduating from the Technical University of Aachen and completingthe Academy of Arts in Düsseldorf under Hans Hollein and James Stirling in 1984, Ingenhoven decided to build a practice of his own.
Now with offices in Düsseldorf, Singapore, Sydney, and St. Moritz, Switzerland, ingenhoven associates, a 100-person firm, launched in 1985 when it participated in an anonymous competition by invitation for a Bundespost building in Cologne. Ingenhoven formed the initial team with three former classmates from Aachen; together, they laboured for several months on drawings – and they won, outperforming the likes of Gottfried Böhm, the 1986 Pritzker laureate. The project was never built, however, due to the Bundespost’s split into three divisions shortly afterwards.
The firm went on to win several other competitions, including a shared first prize in 1991 together with Norman Foster for the Commerzbank Headquarters in Frankfurt. Foster’s project went up, Ingenhoven’s didn’t. Finally, also in 1991, it won a competition for the design and construction of the RWE Headquarters in Essen. When built in 1997, this early green building became Ingenhoven’s first ground-up completed structure. It incorporated a garden, exterior glass elevators, a double-skin facade incorporating operable sunshades, open ceilings, a reliance on concrete thermal mass and natural airflow. Energy efficiency and sustainability has long been the firm’s single most holistic focus.
Ingenhoven’s more recent high-profile projects are all over the world; apart from 1 Bligh Street, they include Marina One Singapore, a mixed-use high-rise complex with a striking green oasis (2018); Toranomon Hills Tower in Tokyo, with its characteristic hanging gardens (2022); 505 George Street, a 79-storey building, which – when completed in 2024 – will be Sydney’s highest residential tower; and the highly anticipated Stuttgart Main Station, one of Europe’s largest infrastructure projects in Europe, an international competition–winning design dating back to 1997. In the following interview with Christoph Ingenhoven, we discuss whether his architecture can be described as high-tech, and the need for all architecture to open up new directions and not only strive to be beautiful, although all of his buildings undeniably are.
Vladimir Belogolovsky: You have said, “I’m very interested in aesthetics, but I never start a project with a formal idea.” What is your design methodology? How do you start a project?
- Cristoph Ingenhoven
Too often architects focus on the image and the surface of things in their desire to make a beautiful building. But that’s not how I think. We start with a blank piece of paper, and I never do a sketch first. Instead, we discuss what needs to be done. Architecture is about thinking, researching, being open-minded, and looking at what others did — in different ages, regions, climates, and cultures.
For example, our 1 Bligh tower in Sydney assumed a compact elliptical plan to better integrate with the surrounding buildings, maximize harbour and city views, minimize solar heat gain, and benefit from spatial efficiency. We also lifted the entire structure 20 metres up to give its footprint back to the city; people can enjoy the sun on its stepped plaza. On the other side is an atrium that runs the entire building height. There is a public garden on the roof. It’s all about openness and transparency—the private offices also look onto the atrium. Many clients wouldn’t opt for such an approach on their own. But when you present people with compelling ideas, they often follow. The beauty of the spaces convinced people to rethink their preconceptions. All of those elements together make the building very special. And its elliptical form allows it to curve gently away from the surrounding buildings.
Every decision was based on numerous discussions and experimenting with geometry, space, views, efficiency, functions, etc. We also tested whether a double-skin facade would make sense in Sydney, and it did. The building demands the highest office rents in Australia, but it is also the country’s most sustainable building and very prestigious companies have chosen to call it home, including the Sydney office of the Prime Minister.
What are some of the key intentions of your architecture?
First, we do not use more resources than necessary. We aim to be resourceful and disciplined. And we build buildings for people to enjoy. We always think about the experience people would have in our buildings. Nowadays, many people talk about making greener and more sustainable buildings. But can architects honestly say that being sustainable is our primary concern? Are those questions truly at the core of our thinking? I don’t think so. We need to try harder. The problem is bigger than the solutions we can currently offer.
When describing your work, you use words and phrases such as “transparency, clarity, plausibility, truth to materials, legibility of the constructed form, durability, future-oriented, and timeless.” How else would you describe the kind of architecture that you try to achieve?
I would add understandability. When we design a building, we hide nothing. I don’t believe in magic. I believe in decisions that are rational, conscious, and reasonable. That’s how solutions can be improved. I don’t get into theoretical or philosophical debates. Architecture should be measurable and tangible. We should think about providing shelter for people and how to solve actual problems. Architecture that doesn’t prioritize those issues is always bad. Architecture is not a caprice but a necessity.
Your work is high-tech, in principle. Could you touch on your key inspirations and references?
High-tech is a problematic definition for me because it is primarily a style. Many so-called high-tech architects are so enamored of machines that they put them on display. In my view, making a show of them is frivolous: it multiplies surfaces and is a nightmare in terms of maintenance. Machines should be hidden or covered. So, I would hesitate to call my work high-tech.
What I appreciate in the work of some high-tech architects, like Norman Foster, Richard Rogers, and Renzo Piano, is that when Post-Modernism became fashionable, they were not part of the hype. And when Post-Modernism passed, their works looked modern and timeless. They also raised environmental questions. And their buildings are definitely beyond exceptional. All in all, they are experimental architects. But those I admire the most are not only innovative but also combine their work with local traditions and spirit. Particular examples include Arthur Erickson, Harry Seidler, and in more recent years, Glenn Murcutt. Their architecture is honest and site-specific. Every building should respond specifically to its location. But many so-called starchitects essentially do the same building wherever they are invited to build.
You have said, “Our buildings are not just expressions of the rational engineering aspects, but we also seek the emotional and poetic characteristics of architecture.” Could you elaborate?
That’s not a contradiction — buildings can be both rational and emotional. Our Stuttgart Central Station is rational because of how it occupies its site at the very centre of the city; it is underground and it provides access to a public park. At the same time, it is a stunning building and an emotional, impressive place. Spatial poetics is an extra layer that adds unique qualities. But it is there because there is an absolute need for it in the city.
One of the most beautiful buildings that I admire is Alhambra in Granada. Beauty was, of course, on the minds of this building’s creators, but there were also so many other aspects: to provide shade and calmness, cool air in the garden, to celebrate the sound of water, and so on.
Of course, things like increasing the span and making the lightest construction possible have always been architects’ goals — from the Hagia Sofia to the Gothic cathedrals. Dedication to beauty is an ongoing project. And it is in my genes — I can’t stop thinking about making things beautiful. But I am also driven by my conviction that beauty results from the right decisions. The point is to make buildings seem effortless, meaning no one should see how hard it was to achieve that. It’s like hearing a great pianist’s performance; the beauty goes far beyond technique. Yet the effort is not apparent. For architects, it’s the same. When we see something extraordinary, we tend not to think about the effort put into it or even the price tag, right? [Laughs.] Of course, the outcome should aim at being sustainable.
Based on your experience, what country right now welcomes architectural innovation the most?
I would mention places like Switzerland for their very high standards for craftsmanship. They can also afford to build good buildings that are sustainable, safe, and well-composed. But if you are looking for innovation, meaning doing things differently, Germany is still a good place for that. We are not as wealthy, but we are rooted in a tradition of invention. Look at our car industry: There is a drive to do better. Thinking about improving how machines work is very German. Also, we continue to make buildings lighter; an excellent example of that would be Munich Olympic Stadium by Frei Otto. It’s crucial for architects to show a different way of thinking and open up new directions. For that reason, I am also a fan of California — people there are inventive and know how to market their inventions. Not necessarily in terms of architecture and urban planning but how we will live in the future: How to build free-emission buildings and vehicles and produce less CO2. We urgently need to focus on innovation. Of course, we can reduce our demand, but population growth will offset that. We need a new source of energy that is safe and, hopefully, inexhaustible.
Regarding architecture, we should look to Singapore for bringing greenery into buildings, Africa for being resourceful, and major cities such as São Paulo and Mexico City that try to improve conditions in slums and prevent them from spreading. Then there are fashionable centres in California, Copenhagen, UAE, and China, where spectacular architecture is produced often. But I think many of those projects are missing a sense of scale, attention to detail, and, most importantly, focus on people. Architects should think more about repositioning themselves and be more conscious about whom they serve. So often, architects serve dictators, not people. There is a global need for a very different attitude.
You have said, “As an architect you must try with everything you do, every sketch, with every single line you draw, to take responsibility to try to make things better, more peaceful, more livable, less conflictive, easier, and more beautiful.” Anything to add to that?
Only that it is all a lot of work. I still spend many hours drawing, and with every line I draw, I question if it is the right one. We think about every detail. Mies was right when he said, “God is in the details.” Even the smallest details should be meaningful.
All images, except for Cristoph Ingenhoven portrait, © ingenhoven associates / HGEsch
German architect Christoph Ingenhoven on his most vital works, the definition of high-tech architecture and how to build free-emission buildings.