Null- und Minergiehäuser
Project: Freiestrasse 87, 8032 Zürich

Energy-oriented renovation with roof extension


This semi-detached apartment building at Freiestrasse 87 in Zürich was built in 1939 as part of an overall development with 4 double-apartment buildings and is in the district preservation area in the English quarter of Zürich-Hottingen.

The structure and equipment had not changed since the property was built. In particular, the position of the kitchens and bathrooms was no longer suitable for today’s requirements. Re-situating the kitchens and bathrooms on the ground plan gave the apartments more space and a more open connection between the individual rooms. Extending the unused second attic storey gave the existing penthouse apartments an extra room.

The whole building envelope is well insulated and, with controlled domestic ventilation, meets the Minergie standard for new builds. There is a photovoltaic system installed on the pitched roof, which covers the energy demand for the brine-to-water heat pump.

Null- und Minergiehäuser
Seebahnstrasse 143, Zürich

Addition of an extra storey and extension on the courtyard side


The renovation added an extra storey to the building. The courtyard façade was reconstructed from prefabricated wooden elements and moved outwards by one and a half metres. Kitchen and bathroom could then be redefined. The apartments were given balconies and access provided by a lift. Two new shops, six 3-room apartments and two 5-room maisonettes with a large roof terrace with views over the city were added. Specific measures were taken to reduce energy consumption to the Minergie standard for new builds.

Null- und Minergiehäuser
Magnusstrasse 28, Zürich

Affordable cooperative apartments


This apartment building in Zürich needed complete modernisation. By taking full advantage of the building regulations, it was possible to raise the new roof on the courtyard side by enough to add one complete storey and therefore more living space.

A large balcony could be added on the courtyard side.

On the normal storeys, the whole bath, kitchen and corridor area was redesigned, while cabinet units with fanlights divide the rooms and provide a lot of storage space. The new part is characterised by a seamless floor covering, contrasting with the refreshed parquet flooring in the rooms.

The building meets the Minergie standard for new builds.



Swiss Solar Prize 2007 and Watt d'Or 2008

Urdorferstrasse 36, Schlieren

​Renovation of apartment building with new penthouse storey

Null- und Minergiehäuser

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