Extension Herdern Railway Service Facility

The new service facility in Zürich-Herdern enables SBB (Swiss Federal Railways) to handle new trains that are up to 400 metres in length. Entire Intercity compositions can be driven into the facility to be cleaned and serviced without having to be disassembled first. Thanks to its central position and sheer size and length the new building possesses a special significance in urban design terms. It emphasizes the urban edge beside the magnificent emptiness of the area of tracks and greets visitors arriving in Zurich by train by signalling that this is where the city centre begins. At the start of the competition many decisions with regard to the design had already been made by the SBB or were defined through the position beside an existing facility. Parameters such as size, placing on the site, the functional layout, the grid of the basic structure and so forth were already givens. Our team was headed by engineers; the architects’ job was limited to ‘giving the monster a face’ – that is to say designing a facade that would be more than just a technical cladding. We concentrated on the southern facade where we focussed our design energy and the limited budget available. On account of the building’s repetitive internal structure we worked with modular elements. In response to the building’s length, and aware of the danger that it could end up as a box without any scale, we came up with the idea of an expressive sculptural modelling. The rounding of the fibre cement elements creates a play of light and shade. The modulation extends across several elements in order to generate a scale that takes account of the building’s enormous length. The size of the curves and projections of the elements is reduced from top to bottom on account of fire protection guidelines and the need for a fire truck access route. It is only at a height of four metres that they are large enough to produce a three-dimensional cushion effect. Both ends of this service facility are smooth and open through large black metal doors to allow trains travel in and out. The flat cross-section of the spatial facade here creates an ornamental figure somewhat like the cross-section of an extruded profile. For cost reasons the northern facade is clad with standard corrugated fibre concrete elements.