Luchsstrasse, 9450 Altstätten
Competition, 1st Prize 1995
2000 – 2002
Canton of St. Gallen
A three-storey, compact building houses a prison and an investigation office. A grid of cells determines the structure of the building. The corridors are arranged like a pinwheel, so they always lead to the facade. All the cells are located on the top floor and have skylights. These allow natural ventilation and zenithal light to fall into the rooms. A fixed, narrow window at eye level gives the prisoners a view of the surroundings. This way of organising the cells reduces the risk of collusion. All the infrastructure rooms for the prison are located on the middle floor. The entrances for the prison and the investigation office lead past the common control centre on the ground floor. This is where visitor control takes place for these two areas as well as for prisoner transport, which is adjacent to the control centre at the rear. For operational, fire protection and safety reasons, the vertical access to the building is via two staircases with a lift system. More
The massive concrete base of the ground floor and the dark, grey-green facade made of Eternit tiles characterise the appearance of the cubic structure. The windows on the top floor are designed in such a way that the solar-shading of the cells is guaranteed without any further measures. On the first floor, the louvres integrated into the grilles provide shade without visually emphasising the prison character. The pinwheel-like internal structure is reflected on the outside in the four equal, asymmetrical facades.
Due to the poor subsoil, the building has pile foundations. These were designed as “energy piles“ for a ground source heat pump. Since the groundwater level is high in the area, the building has only a minimal basement to accommodate the building services. The ventilation systems are located on the roof.