UTRECHT – Since 1973, the year in which a gigantic indoor shopping centre was built next to and over Utrecht’s Central Station, this urban location has been one of the Netherlands’ more unattractive spots. More than 40 years later, an attempt – comprising a number of well-targeted interventions – has finally been made to do something about the unsightly effect of barriers and disorganization in this part of town. Playing an active role in the process is the municipality itself, which commissioned Kraaijvanger to design a new building for the city’s council offices. The building, which acts as a landmark, facilitating orientation, rises from an elevated square that is shared by a station exit. People leaving the station on this side have a good overview of their surroundings and a solid sense of where they are.
The building satisfies another long-held desire. Utrecht’s municipal services, previously spread across the city in no fewer than 15 locations, are now together under a single roof. (Only the more prestigious rooms, such as the council chamber, remain in the old city hall at the centre of town, a building that Enric Miralles renovated in 2000.) Although 14 of the 15 services had been housed in rented premises, the municipality did not want to touch a raw nerve among the citizenry by vacating those offices and leaving them empty. For this reason, the repurposing of old public offices became part of the plan to relocate all services to the new building – an exemplary approach to urban redevelopment.
The challenge for architect Dirk Jan Postel of Kraaijvanger lay in making a 64,000-m2 building hospitable, while giving it a very small footprint – next to and partly on top of a station hall that is currently under renovation by Benthem Crouwel Architects. Postel: ‘It was important to arrange public functions, which occupy the first five storeys of the new building, on overlapping floors around an atrium, to make orientation easy for visitors.’ To provide offices on the upper floors with sufficient daylight, the architects designed an abundance of voids and internal gardens and, above the 11th floor, split the building into two volumes.
Talking about the building in terms of structural engineering, Postel says that ‘one part of the building holds the other like a ballet dancer holding his partner as she pirouettes on her toes’. His analogy explains the supporting members that are visible in the façades. Postel: ‘Our use of cross bracing was partly structural, partly intuitive – the latter based on a feeling that it ought to wrap the entire façade. It took some complex calculation and extra steel, but it created a completely different image from anything you’d get by thinking only from the perspective of structural optimization.’
Seen from any perspective, the façades are a tour de force. The demands of the building site meant they had to be lightweight, to satisfy strict safety regulations and to counteract rail-dust contamination. The architects opted for a polyester composite supplied by Scheldebouw; after fabrication – a process involving vacuum curing in enormous moulds – the storey-high panels need no further treatment. ‘At this scale, it had never been done before,’ says Postel. ‘We spent months learning how to manage the process.’ The result is a gleaming white building with a lively, modern appearance.