Weinbergstrasse, Zurich

The office building on Weinbergstrasse in Zurich’s Unterstrass quarter was erected in the early 1970s, today most of the building is occupied by the ETH. It consists of six storeys above ground level, three below ground and has a central staircase core. Apart from elements at the basement entrance driveway that were added later, the building envelope is still in its original state. While the loadbearing structure is robust, the facade cladding, the dilapidated windows and the outdated building services urgently require attention.

The ETH Foundation, the owner of the building, commissioned Fischer Architekten to examine two options: on the one hand an overall refurbishment of the existing building for use as a flexible office block, on the other the complete or partial demolition of the existing building and the construction of a new one.

A comparison of building volume, circulation, maximum possible use, construction costs and greenhouse gas emissions clearly showed that a complete refurbishment is preferable from the architectural, economic, and ecological viewpoints. This is to become a flagship project for the ETH Foundation with regard to sustainable building and innovation: the goals include strict sustainability certification and the reuse of existing building elements. The latter as part of a circular construction approach and, in the case of the facade panels, in order to preserve the building’s external appearance. In addition, the possibility of collaboration with various ETH research groups that deal with themes such as daylight optimisation, sustainable building, digital building technology or robot assisted production is to be examined.