The 190-meter tall Omniturm in Frankfurt/Main is the first project BIG has realized in Germany. Why not before now?
Kai-Uwe Bergmann: To be honest, we have been waiting almost a decade for a chance to design a building in Germany. And we are delighted that we have now succeeded.
What were the most important ideas you were able to realize in Omniturm?
Kai-Uwe Bergmann: So far what has been produced in Frankfurt were those typically European mono-functional office towers. What we wanted to bring to Germany is what I call the “American Approach” – where you have various functions stacked on top of each other in a tower. This idea that Rem Koolhaas described very graphically in his famous book “Delirious New York” can also be found in Omniturm: Alongside offices there are public areas, hospitality and residential apartments. The apartments are designed to help make a 24 hours vibrant banking district.
How are these various functions arranged in the building?
Kai-Uwe Bergmann: The podium accommodates public areas, restaurants and the like, above that there are office floors. What sets the tower apart are the seven residential storeys that we inserted between the office floors. The former slide outwards in relation to the rest of the tower and the projections and recesses arranged according to their solar orientation form full balconies and French balconies for the occupants.
You yourself live in a highrise in New York. What makes that so special?
Kai-Uwe Bergmann: When you live in a highrise you have a completely different connection to weather phenomena. From that high up you can, for example, follow the formation of clouds. You can see when it rains or snows in one part of the city, but not in the others. You also gain a different perception of the city landscape – I call this an atmospheric scale of the city. You suddenly see yourself as a part of this coherent urban fabric.
What challenges does a mixed-use tower like Omniturm pose to the architect?
Kai-Uwe Bergmann: Naturally, combining various functions with one another in a single building is a complex task. In fact, it is at least as complicated as it is to convince banks, insurance firms, developers and investors to approve such a project. Often, they lack the courage to take on the potential risk of a “mixed-use” undertaking. So, we are very grateful to the real estate developer Tishman Speyer and the engineers at Bollinger + Grohmann for realizing the Omniturm.
Living space is getting scarcer in large cities and consequently apartments are getting smaller. Why should people accept that?
Kai-Uwe Bergmann: Anyone who lives in a city has to weigh up the advantages compared with the limited space available and the importance that is then transferred to the public realm of a city. You have all the stores you need around the corner and can walk or use public transport to reach virtually every location in the city. And naturally you have access to all manner of public facilities in the vicinity. For example, Omniturm offers its occupants a wide range of communal spaces.
How did you design the apartments in Omniturm so that despite the relatively small area there is no sense of feeling cramped?
Kai-Uwe Bergmann: Where space is limited you naturally have to ensure the floor plans are as efficient as possible. For example, we almost completely eliminated halls in the apartments. On the other hand, thanks to the room height, the terraces and immense windows we generate a feeling of spaciousness – even without an enormous surface area.
What technical challenges has the mixed-use concept involved?
Kai-Uwe Bergmann: Well, for one thing you need a different kind of access for this kind of tower than you would use for a pure residential or office tower. Previously, different elevator systems would have been necessary. Today, thanks to modern control systems that is no longer needed and nonetheless all the residents and employees in the building have access to more carrying capacity.
Your impressive exhibition “Formgiving” recently came to an end in Copenhagen. In June a book by the same name will be released by Taschen-Verlag. What can we expect?
Kai-Uwe Bergmann: Our first two books “Yes is More” and “Hot to Cold” were more or less catalogs for the eponymous exhibitions. This time the book is much more independent and seeks to explain our ideas on designing the global environment by providing specific examples. We end the book – as was the case in the exhibition – with our most visionary projects: Architectures for life on the moon and Mars. And it should be mentioned that these intellectual games provide food for thought for how we might improve living conditions on Earth.