Caruso: I wrote an essay in the catalogue of Thomas’s 2020–21 show in Leuven to stake my claim to this. I think I was the first person to work with architecture students to make large-scale models, specifically to make photographs. Making models and photography were always important in my teaching, and early on I found a way to combine them. We also made a lot of models in the office; Peter is a master model builder. And as soon as we worked with Thomas, we changed the way we made models in the office. Where we previously would use “real” material, like timber and natural card, after the Fondation Cartier show, we started to make the structure of the models with foamcore, which was then lined with colored papers and or papers printed on the plotter. The models are usually at 1:20 or 1:50 scale, but because of the abstraction of the paper surface, the scale of the photograph becomes more ambiguous. They could be full-scale, even without the signs of material and construction.

We made models because we were against perspectives. The generation before us represented their architecture through perspectives. The model does something different. You can make a model earlier, knowing less about the design. You can make quite a big model with not so much detailed information; you can look at the model from different viewpoints; you can easily change the model. Peter and I would talk about a design and make sketches, then as soon as we could, Peter would make a model which we could look at and change. This process challenges the idea that the sketch is the “moment of genius.” That might be the case for some architects, but for most it is not. Designing is more iterative and more a collective task. For students working in groups, it becomes a process of making decisions by talking and looking and altering the model. It is closer to how most architecture is made: not about the single author, but about choosing.

Rail: How was this different to what everyone else was doing?

Caruso: I guess other people, especially bigger offices, were embracing computers. We decided around 1992 to buy a Mac for admin stuff, and a table saw rather than invest in computer-aided design (CAD) software. We continued to draw by hand and made models with the saw. It was only when we won the Walsall competition that we invested in CAD. I am not anti-computer. We use building information modeling (BIM) extensively in our office, which has enormous potential, especially when working with existing buildings. We also increasingly do renderings from the 3D model. Some of these renderings look like paper models!

Rail: Thomas’s work is relevant now partially because of this nascent image technology that has become so ubiquitous.

Caruso: With AI you can easily make images that look like card models. Things become seamless between the physical model, the photograph of the model, and the AI image. Thomas was an influence with regards to our image-making and how we engaged with color. When we were doing the Nagelhaus—which unfortunately didn’t get built—we would talk about color with Thomas in his studio with his full range of Pantone colors. We would look at all the swatches, and we would look at a Rembrandt painting, and we would talk about what brown means and how it works at different scales. It’s a very interesting thing to have a conversation about.

Rail: How do you use color in your practice?

Caruso: We’ve used color for a long time, and I’m not scared of it! We have the Japanese color book, which Thomas told us about. Since then, we have used it on probably half of our projects.

There are so many orthodoxies about color. Architects are scared of doing something which is vulgar, and avoiding color is part of that fear. Rem Koolhaas does things which are vulgar, which is often interesting. But don’t you think most architects are always trying to do something which is in good taste?

Rail: I think people are paranoid that it looks dated.

Caruso: But are white interiors or gray interiors better? If you look at the full historic range of architecture, white was a choice, and it wasn’t very present most of the time. This general fear of using color has been a powerful motivation for our using it. We started using materials in their raw form, and then we started to introduce color. We did an apartment in Switzerland recently, and one of the ideas was to look at the wildflowers on the Alpine pass above the apartment, looking at the changing colors from the spring, through the summer, till the beginning of autumn. I took pictures and tried to match the flowers with color swatches. What a beautiful thing to make a project about.

Rail: I interview architects who have an art practice, not architects who only design art spaces. You’re actually on the edge of that. What is the difference between art and architecture?”

Caruso: I think architecture and art are very different. Art is more autonomous. You’re not a professional when you’re an artist, and you don’t have any specific responsibilities to society, which architects and lawyers and doctors have. I think architecture can still be full of ideas and creativity, but unfortunately in the last ten years, there has been a greater expectation for architects to just be service providers. Many important decisions are made before the architect becomes involved, and the project becomes more a matter of “this is what you have to do.” How a project is framed is even more important than the design.

Practice needs to be more than being a service provider: you must try to locate your practice within a larger cultural context. Louis Sullivan worked under very brutal conditions, you could say, as a service provider. Maybe because the instruments of capital were still developing, he usually found sufficient freedom to bring an eloquence to his projects. The Guaranty Building is an efficient office building, but its design is also saying something profound about the conditions under which the building was made—even about the conditions of working in the building. We recently completed an office building next to the Hardbrücke in Zurich. The project is just about being next to this major road viaduct, and we won the competition because our project was the simplest. It’s a very reduced project which nonetheless speaks of where it is, the conditions of its production, and something about the future of that place. That is in some ways cultural, because it’s expanding the content of the project beyond solving the “problem” of designing an office building.

Rail: There is an abundance of things in architecture. Architecture is absorbing all problems, situating itself within the city, integrating with the supply chain, in policy and financing. Architecture is incredibly receptive; it’s also very noisy. Everyone wants to be involved in speculating about the city, in changing banking, adapting and making new forms, and relating it all to how carbon works. Architects have always been involved in deeply rooted parts of the economy, and I see Caruso St John as being part of that project. History is used explicitly as something exciting that we can keep manipulating.

Caruso: I think most architecture has almost nothing to do with reality. Only one or two percent of buildings in the Western world have anything to do with an architect. New construction is still the general expectation, but we should not be demolishing buildings to build new ones. Most of the complexity you’re referring to has to do with a client realizing their own financial viability and their unrealistic expectations of financial yield in a single project. Over time, and with the loosening of the banking system, those expectations have changed. That’s not real. That’s a fiction that could be rewritten. Not enough architects acknowledge this.

In the 1980s, there was a massive deregulation of banking. The big change with this financial big bang was that banks could suddenly become proprietary investors in real estate, amongst other things. As a result, there was a dramatic increase in the amount of towers in cities like Boston and San Francisco within ten years. This was purely about real estate and the new reality of capitalist financing. This is of course a reality, but it is not an immutable one, which is the way most people talk about it. If we wanted to address the issue of affordable housing, a change in the laws about how banks or pension funds can invest in real estate, making renovation as attractive as new constructions, these shifts could make a big difference.

The climate crisis is a reality. If we want to reduce the amount of carbon consumed by the built environment, demolition needs to be made more expensive, existing foundations must be reused, decarbonized energy sources should be reflected in the building regulations. All these things are perfectly possible to achieve through legal means.

These are not architectural problems; they’re political problems. If one loves the full gamut of architecture and building, one is much more able to see the potential in a seemingly unpromising situation. When we have a project in an existing building, all I see is enormous formal potential. At school, good projects in the studio which engage in an intelligent way with existing situations have an overabundance of formal invention. Our references are formal, but also historical and social. I haven’t lost my enthusiasm for these things, but there are fewer projects in the office where one is able to indulge these enthusiasms in a substantial way.

Rail: You’ve done four research books on obscure architects.

Caruso: I did these books with Helen Thomas and they can be seen as challenging the canon. They are about modern architects who I think were engaging with their times in much more profound ways than more famous modernist architects. For instance, Fernand Pouillon built tens of thousands of apartment units at the same time as Le Corbusier built a few hundred. Most of Corb’s buildings have encountered social and economic problems, while Pouillon’s have mostly been continuously inhabited and are popular places to live. They were built as commercial developments and many with stone, which once again is very relevant.

Fernand Pouillon, Rudolf Schwarz, and Asnago Vender all started their careers between the wars and practiced mostly after the war. They are all involved in the postwar reconstruction. They were working within “normal” professional situations but all managed to make work that is extraordinary in what it says about those situations. The buildings are critical in ways that are still relevant today. Until we did the books, there were only French books about Pouillon, one Italian book about Asnago Vender, and German books about Schwarz. So we wanted to make this work accessible to an English readership. The last book about Michael Hopkins tries to shift perception of that work, which has previously been discussed only within a high-tech discourse, into a more European and urban one. Helen’s essay in the book, about the English establishment in the times of postmodernism and Thatcher, is worth reading. The four books are about modern architecture which is not modernist, about architecture that does not rely simply on rhetoric for its value, about buildings that still have energy and presence today.

Rail: Architects are always searching for material to design through. Aldo Rossi, Colin Rowe, Rem Koolhaas, Denise Scott Brown, and Robert Venturi: they looked at cities very explicitly as the source material for architecture—looking at the city as the way to think about a building. What is always so refreshing about your practice is that it looks at buildings as the source material for buildings. Was that an explicit shift for you?

Caruso: Rossi and Venturi’s cities are very idealized pictures of the city—the analogical city, the American city, Las Vegas. Of course we were influenced by those pictures, but maybe I am tired of them, and no longer see their relevance. We have done big urban buildings, and we’ve also done projects that arrange several buildings together into an ensemble, like the St Pancras Campus, where we are trying to consolidate things that are happening in the city around our project. The idea that an architect would plan a city always seemed absurd to me. You could only plan a city as a financial instrument, or as a political one, and that is really a slippery slope.

Rail: I’m interested in how you’ve reclaimed certain types of abstraction. I’ve been invested in this flattening of history as a type of abstraction. Reality is embedded with history and references. Old things seem new, new things seem old.

Caruso: Peter and I have always been more interested in removing abstraction. Concrete reality is almost always more powerful and more complex than concepts. The generalities of abstraction are perhaps how power continually consolidates and persists. It is the granularity of real experience that can offer alternatives. Think about Richard Serra’s Strike: To Roberta and Rudy (1969–71). You go into a small gallery, and this plate of steel is stuck in the corner. You understand its danger, you understand how precise it is. The work requires that corner; it only works in a gallery of a certain size. Those things are so specific. Those are the things we were hoovering up at the beginning of our practice in order to engage with the physical reality of a thing. We only had enough money to attend to sixty percent of what was there; sixty to seventy percent would remain as it was. That really concentrates your mind and forces a kind of poetic efficiency.