Signal Station Zurich

The building is located at the corner of the railroad property and Hohlstrasse street near the Gottlieb Duttweiler Bridge, serving as a transition between residential development and the industrial zone. The signal station is used for monitoring rail traffic in the area of the Zurich train station.
The three-story structure forms a blunt body, which was polygonally vaulted in a competitive project according to the roofs of freight cars. The final version uses this motif in the line of the cornice.
The top floor is used as office space and staff facilities. The lower floors contain technical equipment with space for the monitoring mechanism, a transformer room, an electric generator, emergency batteries, and a fan. Thus, the machines occupy most of the space of the building. A byproduct of the technical equipment is waste heat, requiring the rooms to be air-conditioned. The construction of the air conditioning system is designed to store and release the required amount of heat into the surrounding environment. The thermal inertia of the mass of the double concrete insulating wall is used as a temperature stabilizer to absorb heat generated by the machinery, which is then distributed as needed to individual spaces. Reinforced concrete is used as a protective shell for highly sensitive electronic circuit components against potential damage from railway traffic.
During construction, the concrete was stained with a reddish color from oxidized iron, using the same chemical base as the metal particles contained in the corrosion of the wagons. The artist Harald F. Müller selected colors for the interiors. The rooms are formed by an inserted wooden cube and are designated by different colors that reflect the immediate surroundings: shades of indigo, yellow, crimson, and reddish brown.
The small number of openings on the facade corresponds with five large windows on the top floor, which allow for a full visual overview of the railroad property.
The windows are glazed with coated glass that reflects light and heat into the interior (in summer, adjusted by blinds controlled by a central computer system). The windows, glowing at night and reflecting during the day, are an interesting changing element of the structure, thus communicating its function as a signal box for the railroad.