Ben van Berkel: In a certain sense, yes; but above all it’s meant as a provocation. There’s a misunderstanding about the word “design”. It means different things in the English- and German-speaking worlds (and in Dutch). In the latter case, there is almost a stigma attached to the term “design” nowadays, which is associated with superficial, fashionable trends. We don’t wish to abolish design altogether in architecture, but we do want to resist the notion that it’s merely the outward presentation of something one has created.
Detail: In the past, you used diagrams a lot as design instruments, like those that depict the airflow around a spaceship. What is new about “design models”?
Ben van Berkel: Today, there are almost unlimited possibilities for designing a building – plus computer programs that allow any form to be created. Nevertheless, in many cases designs look alike, instead of exploiting the potential for diversity. We believe this is attributable to the complexity of architecture. “Design models” are a means of breaking down this complexity and developing a disciplined way of working. Artists and fashion designers are a step ahead of us in developing design methods. They manage to be innovative by concentrating on one specific area and initially setting aside other aspects: for example, by focusing on colour in a fashion collection. Once you’ve settled on a theme like that, it’s not difficult to find the appropriate material to bring out the colour to greater effect. Or think of Andy Warhol, who adopted the printing technique of Roy Lichtenstein as his starting point and then created something entirely new and independent by overpainting it.
Detail: What does the digital revolution mean to you in terms of design strategies?
Ben van Berkel: It plays a really decisive role. With the aid of computer-supported design, we can radically evaluate the basic typologies that have evolved in building history and work with new ingredients. To understand that, one has to consider the ordering systems in use hitherto. The “ingredients” of modern architecture are columns, floor slabs and open glazed facades. The orthogonal grid or collage is a popular system. The new thing about designing with computers is that we no longer have to opt for a particular system. We can combine a number of principles to achieve far more complex results.
Detail: Doesn’t this combination lead to all the same “blob” designs, though?
Ben van Berkel: Not if you always bear in mind what you’re doing with digital tools. For instance, it’s interesting that at the junction of two components, one can control the transition and achieve a flowing form. If you leave both elements more less as they are, you create a collage effect. With an ever greater degree of fusion, you get a hybrid. We illustrated this type of hybrid – in which the starting element remains perceptible, but where something entirely new is created – in the case of the “manimal”, a synthesis of man and animal.
Detail: How has the working process changed for you as a result of using computers?
Ben van Berkel: The whole traditionally linear planning process can be rethought. In the past, we said: “This is the sketch. That’s the model, and from the two we’ll prepare the working drawings.” Only ten years ago, we were working more or less along those lines. In the past five years, we have applied complex engineering technology to find out at an early stage to what extent we can mould a particular material. By entering various materials in our parametric 3D data model, we can anticipate the interaction between forces from the load-bearing structure and external influences. Only when we are certain of what is technically feasible in detail do we return to formal considerations. That’s a revolutionary development with enormous potential.
If I want a sheet-metal facade with a double curvature, I have to consider in good time whether it should be shaped in the factory or on site, or whether I shall reinforce it with fibreglass. That way, facade elements can be made thinner. Using the computer, we investigate the limits of a material in the light of its technical properties. At the same time, we can consider innovative visual and haptic effects.
Detail: Does that mean there are no drawing pens or model-builders in your office?
Ben van Berkel: We don’t start immediately on the computer. If you work exclusively on a PC, there’s a danger that your imaginative, creative potential won’t be exploited to the full, or will be misapplied. We move between the various media and apply experimental techniques, like fashion designers and composers of modern music. Usually we start in a quite playful way by imagining what would happen if the building were a ball, say. Or in the middle of the design process, I introduce a little diagram from a different context. We work a lot with metaphors, but physical models help us in all this – usually quite simple paper models that serve to illustrate an idea clearly. To test a design with various materials, we clothe the building in a number of different ways.
Detail: You could also apply various textures to the digital model. What are the advantages of physical models?
Ben van Berkel: The great advantage of physical models is their visual clarity. They also give you a sense of scale, which is much less pronounced with digital models. We work with digital models as well, of course. When we built the Erasmus Bridge, we learned to appreciate this working method, which is borrowed from the engineers. Today, we use advanced engineering programs like Topsolid and even combine programs to achieve the best solution.
Detail: Do you work with virtual reality in your visualizations as well?
Ben van Berkel: We have experimented in this direction. In Stuttgart, we are planning an office building for the Fraunhofer Society, in which the use of new digital presentation screens is to be investigated. We made many presentations of our project in a “cave” – an all-round projection in which the model is experienced in virtual reality. This is all very interesting, but one shouldn’t lose sight of the real goal. In many cases, the physically built spatial model can show even more. We have a large model-building workshop in the office. Only complex models for construction in rapid prototyping technology do we outsource.
Detail: Could a spatially complex building like the Mercedes Museum be created without the aid of the computer?
Ben van Berkel: Quite honestly, I believe it would be possible, but not in the short time we had available. The clients created conditions under which we were able to work with the latest technical facilities. Since the entire mechanical services are integrated in the exposed concrete structures, every detail had to be agreed with the engineers and the respective firms. Last, but not least, all changes in the plans had to be sent immediately and reliably to up to 500 different parties involved in the project – and on some occasions we had up to 200 updates a day. We were able to convince the clients that in addition to the planning team, we needed five further persons alone to create and maintain the 3D data model. That costs a bit more, but these are the key positions for monitoring the entire planning process. In the case of the Mercedes Museum, we had an external specialist in the person of Arnold Walz, who constructed and maintained a 3D parametric model. In a project like the museum, the points of intersection between the planning and production data are of great importance.
Detail: What is the advantage of a parametric model?
Ben van Berkel: A parametric model means that you’re not only able to define the position of various points in space, but also the relationship between them. In the case of the Mercedes Museum, almost none of the tetrapod columns are the same. We didn’t draw the columns individually, though; we defined the parameters for them in terms of their raking form, slenderness and load transmission. If the radius of the building is changed, for example – and thus the load transmission and position of the columns – one doesn’t have to draw and calculate all of them anew. They generate themselves within the given parameters. The handling of the initial model reduces the risk of mistakes and miscalculations. It also helps to save materials and makes the construction process controllable. We call this “digital sustainability”.
Detail: In view of the intensive use of the computer, do you need a new type of architect in your office? Tobias Wallisser, who supervised the Mercedes Museum project, is an acknowledged computer specialist.
Ben van Berkel: Absolutely! In the 1990s, Tobias was one of the leading minds and a pioneer in this field; but things develop at an incredible speed. I once jokingly remarked to him that he belonged to the Maya generation, because we used to create our 3D models with the Maya computer program. Nowadays we used Topsolid, and most of our young assistants are computer freaks who work a great deal with scripting techniques and can modify programs. A lot of them studied at the Städel School in Frankfurt, where I teach together with the best programming specialists. During their studies, they undergo a period of practical training at UNStudio, before coming back to us after getting their diploma.
Detail: Do you draw on the computer yourself?
Ben van Berkel: I’ve always been interested in design techniques and have been very open to this technology, even though I had a classical architectural training. I’m keen to know the latest techniques. About eight years ago, I began to teach myself the 3D Studio Max program. I know the principles, therefore. But I would not be in a position to sit at a keyboard and build a 3D model on my own. My role is more like that of the composer who directs the orchestra without being able to play all the instruments himself.
Detail: Since when have you been working with digital 3D models?
Ben van Berkel: I think we were at least among the first architectural offices to do this. It began with the Erasmus Bridge in 1992. The assistant who introduced the system at that time is still in the office. The engineers were delighted to be able to carry out their work on the basis of our coordinate model. Maybe the reason why we are so open to innovations in this field is because we began to work with these things at a very early date.
Detail: What influence does the computer have on architecture? Can one now construct forms that would have been inconceivable in the past?
Ben van Berkel: You sense that I hesitate to claim that it’s possible to generate free forms only with computers. But certain forms with which we are concerned are strongly influenced by the potential of digital media. Some of these forms are new; others aren’t. In other words, we have to wait with some ideas until it becomes possible to realize them.
Detail: In what direction do these ideas lead?
Ben van Berkel: Despite the freedom we enjoy, we have to consider the purpose for which these forms are created. The primary aim is not just to achieve an interesting form. I’m far more interested in the spatial qualities we can extract from these forms. The revolutionary aspect of this paradigm shift in design lies in considering how we can conceive spatial qualities in a new way. Maybe one can sense this reorientation at least in some in our buildings.
Detail: Could you formulate that more precisely?
Ben van Berkel: It’s a question of how a building responds to people’s movements. In classical modern architecture, most spaces present themselves to us frontally, whereas we try to create spaces in which one follows individual elements – to the point where you almost have the feeling that the spaces are following you. That’s something quite new, I hope. It’s very important to me, because I believe that is the essence of architecture.
Detail: What design models help you to develop concepts like this?
Ben van Berkel: You need discipline to reflect on how an idea can assume form. You might choose a musical instrument as a design model, and proceeding from there, you could start to think in a completely new way about movement and mobility in architecture. I often speak of kaleidoscopic experiences, although the form is not kaleidoscopic at all. As a result of special effects and perceptions, space can be kaleidoscopic, however.
Detail: In the Möbius House and the Mercedes Museum, you’re preoccupied with endless loops as a spatial concept.
Ben van Berkel: If you run your hands along a physical model of a Möbius strip, you notice that something which turns from inside to outside also represents a kind of supporting structure. The idea of inside and outside as part of a single system is, of course, extremely interesting spatially. That’s something I have observed generally in mathematical models: they contain numerous architectural qualities. Just as the structure is inherent in architectural models, so mathematical models bear the idea of movement within them. Architects have worked for centuries with different mathematical models – the grid, for example. But I think there are other systems that have a great potential, like the creation of what I call a “capacity for endless space”. I’m still working on this, but a number projects have been completed or are in the course of planning that exhibit these qualities.
Detail: Are endless spaces better than previous spatial systems or just different?
Ben van Berkel: I think spaces of this kind can be superior to those based on rigid grids. They are a more efficient model. There are no dead ends in endless spaces, whereas in grid structures there are plenty of them. They are one of the basic principles of modern architecture. If you go back to the theories of van Doesburg and Mies van der Rohe, you constantly come across claims that gridded space affords unlimited scope. But that’s not true. There are dead ends everywhere.
Detail: But endless spaces are much more difficult to construct and much more expensive than orthogonal structures. You just have to think of double-curved formwork to exposed concrete.
Ben van Berkel: Not necessarily. In the case of the Mercedes Museum, people are surprised to hear how reasonable the building was economically when one considers its appearance and what it can do. By integrating the entire mechanical services in the concrete structure, we were able to save a large part of the volume that would otherwise have been needed for services – expensive space be-hind suspended soffits, for example, where it can’t even be seen. The construction costs, at roughly ™120 million, were only a third of those for BMW World. That shows how qualitative computer-aided design can be, but also how effective it is in terms of planning time and costs.
Detail: What do you do when a firm does not have the know-how to participate in this digital process?
Ben van Berkel: That is precluded from the outset. We make knowledge of digital building processes a condition for the award of a contract. All specialist planners and firms are asked whether they understand the 3D model and can work with it. In the brief time scheduled for planning and construction, we have to depend on everyone being familiar with digital techniques.
Detail: Doesn’t it put some clients off to hear that you work in such an experimental way?
Ben van Berkel: We don’t say to clients: “Your building is going to be an experiment.” The experimental character should be understood in an academic sense and is a very controlled process. I think clients get an interesting building from us if they allow us enough latitude to realize the full potential of what lies within their budget. Our new theatre in Lely-stad is a good example of how we break down the complexity of a building by disciplining the design. At ™20 million, it’s economically very reasonable for its size. The experiment lies less in the form than in the coloration. The exterior of the free-standing structure – set in somewhat dismal surroundings – is in a cheerful orange and has an animated form. The foyer, conceived as a vertical space that opens to the sky, is pink. The auditorium is deep red and directs the entire concentration of the audience to the stage at the front. Experiments in colour and spatial changes like this interest me: you pass from one world into a completely different one.
Detail: What do you understand exactly by “disciplining complexity”?
Ben van Berkel: I developed this strategy for the Erasmus Bridge. It was the first project in which I applied repetitive systems to a certain degree to reduce the complexity. We began by using only 5° and 7° angles, generating the entire structure from this. We followed the same procedure for the Möbius House. Although it looks very complex, it is constructed solely with the angles 5°, 7° and 11°. That simplified the formwork and created a subtle spatial order. We are familiar with principles like this from the music of Arnold Schönberg and Hector Berlioz, for example, but in architecture, strategies of this kind are not so common.
Detail: How did you manage the difficult question of acoustics in the Lelystad project?
Ben van Berkel: Computer simulations exist for that as well. We fed our data model of the theatre into the simulation. The reverberation time was then calculated automatically. Even materials and their surfaces can be changed in a virtual process to assess the acoustics. The results are given by the computer. We are interested in this kind of engineering. In the Netherlands, as in Germany, architects are always trained partly as engineers. But as important as the acoustics were to us, we also wanted to know about the sense of peace and calm radiated by the space. The auditorium in Lelystad is subject to the discipline of the same three angles. This serial row achieves a similarly calming effect to the music of Philip Glass, although this can be extremely complex.
Detail: Do you also use architectural references in your work?
Ben van Berkel: I appreciate the classical principles of architecture. You can learn a lot from them. For nearly ten years, we’ve been going annually to Venice to study undiscovered architects – like Scarpagnino and Sansovino (although the latter has become better known in the meantime). At the AA in the 1980s, we were trained to be artist-architects with many anarchic ideas that I didn’t appreciate so much at the time. Later, though, I adopted some of these ideas in my own work.
Detail: To what extent are you interested in the facade, which is the most important element for many architects; and what role do materials play?
Ben van Berkel: I am primarily interested in space and its organization. Of course I’d also like to create the most avant-garde facade one can imagine. From the outside, the theatre in Lelystad exhibits a certain brutality, which you find in many Dutch buildings, and which was necessary here to integrate it into the surroundings. By using different colours and textures for the metal roof and facade sheeting, the theatre has a completely new look. The two-coloured skin is deliberately rough in contrast to the interior. In the Mercedes Museum, it’s the other way round: the skin is very fine in contrast to the hall with its rough exposed concrete. Right at the beginning of the design work, we consider what recollection of a building observers should take away with them. The most thorough-going example of this is the outer skin of La Defense. As a result of a polyspectral film inserted in the glazed facade, the colour changes through the entire visible spectrum as one moves – from blue and green to red and back again. You can really say that the spaces follow you here. Architecture that does not impart some experience to take home with you is insignificant.
