Architectural experimentation with the Free University Berlin (FU) began back in 1963 when the then Paris-based architects Candilis, Josic, Woods and Schiedhelm won an international competition to build a new campus for the philological institute, which had originally been founded in 1948. The architects' reputations spoke for themselves: Candilis and Woods had previously worked for Le Corbusier and, along with Schiedhelm, had been members of the legendary Team X, which had called for the overthrow of dogmatic design rules stipulated by the Athens Charter.
Consequently, there were high expectations of the design of the masterplan and the first phase of building. What was to appear was a cluster of buildings, only two storeys high, held together by a system of internal pedestrian streets and walkways.
The theory was that this would guarantee maximum exchange between the faculties and between the students.
Communication was regarded as paramount in the design of what was the first building in Germany after the Second World War to use industrialised processes. The striking prefabricated facade, with segments based on Le Corbusier's Modulor rule, had a Cor-ten steel external finish that was to take on the desired rusty patina, and give the building a dark brown colour. Later this contributed to its affectionate nickname, the Rostlaube, meaning 'rust bucket'.
However, soon after the project started on site in 1967, the social, technical and architectural optimism that it typified began to ebb. Problems with the building grew worse and worse over the years and finally, in 1997, Foster and Partners won the competition for the restoration of the old buildings and a new library. So what had gone wrong with this project, a project that was supposed to be an experiment in education as well as in design and construction?
Essentially, the plans for the Free University Berlin were generated by the aspirations of the ideal city. The campus was meant to encourage free social interaction and communication, reflecting continuum and flux. Thus, the faculties were decentralised, with offices, seminar rooms and even libraries spread out all over the campus. In reality, this proved to be an organisational nightmare. Rather than increasing the social and scientific efficiency of the university, it increased its disintegration, eventually giving rise to vandalism.
In terms of structure, the great French engineer Jean Prouvé had devised a system of concrete-encased steel columns - I-section steel beams and prefabricated reinforced-concrete slabs that were simply bolted to the beams. The entire structural logic was based on prefabrication and flexibility; on providing a system that guaranteed the utmost flexibility when it came to quick changes in the departmental layout.
Every element seemed to be part of a gigantic building kit. On the facade, horizontal cladding modules were either 70cm or 113cm wide, with 4cm joints. Unfortunately, the patina of rust did not prevent water getting behind and into the individual facade elements and now some of the old panels show signs of corrosion, similar to a much-loved but rusty car. Water also penetrated into the buildings from the flat roof gardens. These had been provided with large areas of vegetation and were meant to function as social breakout spaces, but in the end the users felt less and less responsible for their upkeep, and poor maintenance meant they fell into disrepair and failed in places.
However, the demise of the Rostlaube was not only due to the rapidly dilapidating building fabric. From the beginning, the project finance had been insecure, delaying construction for years so that the mere 9,260m² net area of the first building phase did not open until 1973, by which time the number of philological institutes had doubled.
Finally, the discovery of asbestos in 1990 sealed the buildings' fate, and only a thorough refurbishment could stop the dangers of advancing decay and destruction.
Foster and Partners had to address all these technical, architectural and organisational challenges. At the time of the competition, the tasks ahead must have seemed daunting, not least because the building had been listed. In its favour, Foster's Berlin office already had significant experience of dealing with historical buildings in Germany, most notably with the Reichstag - a project that was in full swing at the time the practice won the FU commission.
Entering the partly refurbished FU today, you can imagine the colossal amount of detailed documentation that must have been needed to restore such a landmark 'monument'. Leaving aside Candilis, Josic, Woods and Schiedhelm's protestation that the building was not a singular 'monument', but a public 'instrument', Foster and Partners had a great deal of respect for the aims and aspirations of the original architects.
Norman Foster himself took pains personally to investigate the sprawling maze of alternating 'streets', courtyards, lecture halls and endless corridors. The scale of restoration work has ranged from rebuilding the facade down to preservation of some of the original lampshades. Despite minor changes, where the original material could not be preserved for cost reasons, the FU still embodies the social and architectural dynamic of the 1960s.
The most urgent and critical act was to remove 6,000m³ of asbestos and related material. In the process some of the structural rigour of Prouvé was exposed in the not-yetcompletely refurbished wings of the Rostlaube. In the stripped columns and beams, or even the provisional sealing of the old suspended ceilings, we peek back in history at the original.
Particularly now, in its pristine restored glory, the building shows a wonderfully fresh and thoughtful approach to individual questions of design. Nearly everywhere the original manière de penser can be detected - from the sinuously-rounded edges of the facade, some executed in curved glass, to the detail revealed in banisters or windows.
The original colour scheme, based on five radiant colours of red, yellow, green, blue and purple - also used for orientation purposes - has been restored. It is a pure delight to walk on carpets that are once again strongly coloured, and which have been refitted by the orginal manufacturer.
In terms of restoration efforts, the redesigned external Cor-ten facade would justify an essay by itself. Here it may be sufficient to point out that 15,000m² of historical panels, with their characteristic bulges to accommodate bookshelves, have been replaced by new modules clad in bronze. A sample section of several repeating facade units was exposed to the elements and has produced almost the same intense dark and dense colouring as the Cor-ten sheets, though the new material has a less rough surface.
From a distance, the difference will be almost imperceptible in a few years' time. On the inside, the difference between new and old is even less visible. The baked-enamel surfaces will be as radiant as on their first day.
One crucial problem of the old Rostlaube was its dated functional organisation. Working with the FU, Foster and Partners came up with a new spatial concept to make everyday academic life more efficient. It was based on the central idea that each department give up its individual library in favour of one large central facility. The initial proposal was for this to be built on the site of the adjacent car park. FU liked the idea, but the client, the Berlin Senate, did not. It wanted the new library, which contained 700,000 books, to be integrated fully with the historic buildings.
So, at what was probably a far greater cost and much higher logistical expense, Foster and Partners designed a 6,290m² (net area) library which has been accommodated, or 'wedged', into one of the larger courtyards.
The building's shape reaches back into Foster's design history, namely to his studies with Buckminster Fuller and his own 'Autonomous House Project' from the early 1980s. An elliptical ground-floor plan is covered by a curved double-skin shell of alternating metal and glass panels, merging the structural qualities of a geodesic dome with Foster's aspirations of creating an ultimate low-energy concept. In principle, the air circulates, depending on the outside temperature, either freely between the dome's double layer skin or channelled in the basement through hollow concrete floors, thereby thermally activating the library's concrete core. In every aspect the building's odd location must have challenged Foster's creativity, as the new library had to co-exist in close proximity with the historic fabric.
Of all the new library spaces that have opened in Germany in the past few years - even including Herzog & de Meuron's recent Cottbus University Library - Foster's FU must be one of the most exciting. Students can enter the new space from both sides, thus also making the library a shortcut between two wings of the original buildings. The entrances gates are bright yellow, but the 1970s colours give way to white and shades of grey in the rest of the interior. The bigger of the two gates opens up into an enormous spherical space. The eye rises up the four undulating floor levels, which form a symmetrical concrete core. Each floor plate is defined on the periphery by continuous curvilinear reading desks, which create dramatic terraced spaces. Instead of being simply repetitive, the swinging reading surfaces probe the space, almost reaching the internal roof skin, which is made of white fibreglass fabric panels and translucent ETFE elements.
Appropriately, Foster senior partner Stefan Behling calls it a 'light bubble'.
The covering shell, spanning 64 x 55 x 19m, is a double-layered skin with a Mero wide-span steel structure painted in bright yellow. With faint echoes of high-tech architecture and Foster's own historic experiments in that direction, the roof provides a stylistically interesting bridge to the 1970s.
At present, it is difficult to tell whether Foster's efforts at the FU will be honoured more for the dedicated refurbishment of the Rostlaube, or for defining and creating a new university campus with an overwhelming library at its heart.