The commercial and retail building at Theaterstrasse 12 in Zurich is to be transformed into a contemporary, representative “house on the square” and contribute to the architectural upgrading of Bellevue. A study commission by PSP Real Estate AG focused on the conversion and renovation of the 1970s building, which was built according to plans by architect Werner Gantenbein.
The structural designers and façade engineers from Lüchinger+Meyer had the pleasure of supporting EMI Architekten in this process, whose convincing contribution “Comet” received much applause. “Comet” adds a touch of glamour to Bellevue – in the immediate vicinity of the red carpet of the Zurich Film Festival. Its outward mutability between day, twilight and night is inventive. In addition to the reference in name and character to the adjacent historic “Corso” building with its cinema halls, architectural links to the neighbour have also been established. For example by adopting the uniformity of the pilaster-like façade sections and the classicist and symmetrical structure of the design.
The existing supporting structure is treated with restraint and respect. The interventions are essentially limited to areas of new access facilities or serve to improve the lighting situation. The biggest adjustment is on the Theaterstrasse side, where the existing ceiling slabs have to be cut back for the new façade and placed in a tight grid on prefabricated concrete columns or bodies.
The striking pilasters of the square façade are provided in structured cast glass, which is backed with solar cells. The large-format, multi-storey cast glass is made of conventional white float glass, which is heated and shaped using matrices. Due to the geometric structuring, the structural glass elements cannot be visibly butted. The PV thin-film modules are laminated on the back. In combination with the structured glass PV modules, the overall structure corresponds to laminated safety glass. With the selected glass structure the required load-bearing capacity and, in the event of damage, residual load-bearing capacity is ensured.