The commercial building at Bleicherweg 58 in the center of Zurich was built in 1971 and required complete renovation. Except for the top floor, the volumetry was retained. The facades, however, are distinctly more sculptural than before, giving the building a more urban appearance. A new canopy roof announces the building’s address toward Bleicherweg and mediates the street space.
The combination of metal and stone echoes a theme of the buildings along Europaallee, albeit in a refined form befitting the place and the task. The materiality forges a link between the traditional, stony city and the adjoining building from the 1970s. The architectural bronze allowed sharp-edged, precise detailing and promises to produce a fine patina that will no doubt remain differentiated and lively thanks to the strong profiling. Complementary in color, the greenish Zurich sandstone in turn anchors the building on the site and in its history.
The division of the facade follows a tectonic order of pillars and beams, but also speaks its reality as a non-load-bearing envelope. With base and capital, the vertical elements articulate gravity and the load-bearing function in an almost column-like manner. The formulation of the corner on the other hand reflects the cladding. The sandstone panels are encased by frames of architectural bronze which protrude slightly so as to give the impression of three-dimensional staggering of the elements, toning down the joints without completely hiding them. Except for on the top floor, the sandstone is used not only for the pillars, but also to cover the ventilation windows. At the bottom, two axes coupled together articulate the ground floor, with the change from stone to glass forming a crowning floor at the top. The classical effect of these themes, the graceful design and materiality all ennoble the facades. Toward the rear courtyard, on the other hand, the building envelope was rendered in a simplified form in sheet steel, albeit with the identical division.
The precious facing of Carrara marble and Nero Portoro from the existing building was retained in the foyer and on the stairs. New handrails of bronze and lamps of Murano glass forge a link to the new facade. In contrast, openly routed conduits and ceiling elements mounted directly onto the concrete in the office rooms finished by the the tenants, create a workshop feel. Coupling the radiators with the facade pillars enabled full-height windows, thanks to which the rooms—in addition to the good lighting—also benefit from the building’s exposed situation in the city.
Site supervision: Baumanagement Wild, Winterthur
Structural engineer Ferrari Gartmann, Chur
Services engineer: Hürlimann Engineering AG, Bubikon
Building physics: Kopitsis Bauphysik AG, Wohlen
Electrical engineer: IBG B. Graf AG, Winterthur
Facade consultant: Ferroplan AG, Zurich
Project team at Boltshauser Architekten AG
Project leader: Mathias Blondé
Deputy project leader: Marle Freitag, Simon Staudacher
Quantity surveyor: Markus Boltshauser
Team: Christoph Giger, Bettina Germann
Interns: Dominic Brühlmann, Georg
Weilenmann, Gaël Zuber, Helen Rudolph