This commercial and apartment building was built on a parcel located within the city’s medieval perimeter. Thus, the long (23 meters) narrow (6.30 meters) measurements typical of medieval parcelling had to be accommodated. The architecture was strongly influenced by the parcel’s form which was utilised right to the back of the lot and has always had a highly specific floor plan and section in this densely-built context.

The apartments are each grouped around a central courtyard that opens on one side to the neighbouring parcel to the south. This side opening was not only intended to let light and sun reach the apartments but also to allow for the enjoyment of the branches of a large tree in the neighbour’s yard. Like a periscope, the façade around the courtyard is recessed floor-by-floor to clearly separate the individual apartments.

The stairway is separated from the elevator shaft to gain area for the central living space. The apartments are entered directly from the elevator. The stairs at the end of the parcel are an open construction thus fulfilling the additional function of a small loggia.

On the ground floor, a two-story hallway leads from the street along the old parcel wall and allows access to the Swiss Fire Fighting Museum located in the back courtyard. The street façade is made completely of glass and is protected by a cast-iron curtain construction that can be folded back piece-by-piece at will. Wavy light slits lend the curtain construction a flowing textile-like feeling. While the construction hides the living space behind it, its heavy cast-iron material serves as a counterweight protecting against the noisy street side. In both form and material the façade components are related to sewer grates and to the protective grilles placed around trees. Thus, emphasizing they have their origins in the world of the street.