Description

In 2009, the city of Rotterdam announced a competition for a mixed-use building that should be more than just a city hall: an unusual typology that encompassed offices, businesses, housing and a central, public hall. The old building had become too small and the city also wanted to consolidate its administrative departments distributed across 14 different locations into just four facilities. The new Timmerhuis should connect directly to the old building and accommodate 1800 employees from the licensing, culture and sports departments as well as central services and call centres.

The building designed by OMA in Rem Koolhaas’ home town is comprised of modular sections stacked in two irregular towers set back from the street. At first glance it looks as if numerous shipping containers had washed in from the harbour onto the L-shaped site and been stacked on top of each other in pixelated fashion to form an almost 60-metre-high “freighter” in the sky. Due to the irregular layering of the cubic elements, the renderings at the time depicted an airy steel structure with an almost column-less agora (the “City Shop”) at its heart. The visualisation communicated the impression of a plastic cloud that appeared to float above the ground floor, its modular construction subtly connected to the existing Stadstimmerhuis from 1953. After winning the competition, OMA revised the design due to an error in the calculation of the areas, reducing it by several thousand square metres. In addition, the city decided against realising the spacious market place on the ground floor, citing “cost reasons”. These adjustments had consequences for the construction system – a three-dimensional Vierendeel steel structure. Together with the structural engineers Pieters Bouwtechniek, the architects developed a structure made of simple steel struts, supplemented by diagonals and this simpler and flexibly extendable steel skeleton made it possible to rapidly erect the structure within a period of just six months. The time savings meant that more attention could be given to the elaboration of the details and the overall building came in within the estimated budget of 85 million euros.

Inside the colossal 48,400 m² building, the interior is surprisingly spacious and open. One enters the building through a curtain of glass on the west or east sides. While the curved glass elements of the entrances do not make the box structure ascending on either side appear to float, they succeed in setting it apart from the public entrance. On passing through this curtain, visitors enter a large public passage and entrance hall with a height of almost twelve metres that connects the building with the Coolsingel pedestrian zone and the central Laurens-Quartier and also serves as a public square and distributor for reaching the non-public floors above. It is the centre of the building and a meeting place for civil servants, passers-by and residents. Two 7.2 × 7.2 metre large atria are threaded from top to bottom through the grid structure to provide daylight from above. They create visual connections between the floors and express the design’s mixed-use concept. The ground floor of the new building contains a café and the Rotterdam Museum while the old building houses shops facing the streets. The entrance hall is flanked by two circulation cores and access to the elevators and stairwells is restricted to those with a chip card or corresponding permission. The offices of the public authority departments extend over the first four floors of the old building and the first five floors of the new building over an area of 25,400 m². A communal roof garden on the fifth floor serves as a meeting place for residents and employees. The spatial variety and flexibility of the concept is most visible on the office levels: instead of closed office boxes, the work and traffic zones flow into one another. Open staircases connect the floors, which are divided only by meeting areas, groups of seating, lockers and kitchenettes. Large windows onto the atria and gallery connect the floors visually with one another. To promote communication among employees and to accommodate part-time working, a model that is widespread in the Netherlands, no-one has a permanent desk of their own. Instead, every employee has their own locker in which to store documents and can work somewhere else every day if they wish. Altogether 1200 workplaces are available for a total of 1800 employees.

Originally published in Bauwelt 08.2016, pp. 14-21, abridged and edited for Building Types online, translated by Julian Reisenberger

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