“The revitalisation of the Schader office building was a challenge that our team mastered brilliantly. As a specialist in the refurbishment of listed buildings, PORR has applied its comprehensive know-how here: It was important to modernise this historic jewel carefully while building sustainably and conserving resources. The Schader office building will thereby continue to grace General Guisan Quai with its exceptional profile for decades to come”, says Josef Pein, CEO of PORR SUISSE.
The business centre was designed and built by architect Jacques Schader between 1969 and 1973. Today it stands as a representative example of the history of art and culture and is a protected building of importance to the city. The goal of the refurbishment was to do justice to the architecture of Jacques Schader, to preserve the listed building’s fabric and to accentuate it with modern elements.
The contract included the deconstruction of the building down to the supporting structure. PORR renovated listed parts such as the facade, floor coverings in the foyer on the ground floor and in the surrounding area, as well as the plant troughs in the outdoor area, in accordance with the requirements of the monument preservation authorities.
In course of the facade renovation, all sheet-metal cladding of the listed aluminium facade was dismantled, cleaned of pollutants, and stored on site before the demolition work began. In the course of the facade installation, the sheets were reassembled in the same place by the PORR subsidiary Alu Sommer Suisse AG. The windows were modernised to meet today's requirements.
The existing steel supports were also cleaned of pollutants, corrosion protection was applied and fire protection clad or coated. The positional deviation of the existing facade supports posed a major challenge, which PORR solved in an elaborate process.
Extension of life cycle through modernization
In addition to the reuse of the facade, which already saved primary material and raw materials, retrofitting measures on the existing supporting structure reduced backfitting and structural work, which also saved large amounts of energy and materials. In addition, the volume of waste from construction activity was significantly reduced by extending the life cycle of the shell and facade.
The building consists of three basement floors, a ground floor and eight upper floors. The basement levels contain archive and technical rooms as well as parking areas. The majority of the floors above-ground contain office space.
The building will be certified to LEED Gold (LEEDv4 Core & Shell) and Minergie (Standard).
Increased user comfort
The energy consumption during operation can be significantly reduced through the retrofitting measures of the building envelope. This is achieved through optimal thermal insulation of the building envelope, consisting of triple insulating glass, thermally separated aluminium profiles, external sun protection and new roof superstructures. The primary energy demand reduced by these measures is also further reduced by a heat pump powered by lake water to supply the building with heating and cooling.
A side effect of upgrading the building envelope is a reduction in noise pollution in the interior due to the four-lane General Guisan Quai.
Facts and figures at a glance
Scope of services:
Building construction . Office Construction
Zurich Insurance Company Ltd
PORR SUISSE AG
26 months (08.2020 – 10.2022)
Type of project:
Complete refurbishment of a heritage-protected building