Thanks to the donation of a property across from the existing Kunstmuseum, an opportunity arose for a further significant extension to the main building. The dimensions of the competition project respond to the proportions of the historic building by Paul Bonatz and Rudolf Christ, as well as to the scale of the neighboring buildings along Dufourstrasse. With its skylight superstructures and nuanced sculptural relief, the building volume also enters into a dialogue with the smaller-scale historical architecture of the St. Alban district. The structure of the façade and the materials selected facilitate integration of the voluminous extension into the urban fabric, without however foregoing the aspiration of making the new museum building a key player in the cityscape.
Direct access from Dufourstrasse is available for special events. However, the principal link to and access from the existing art museum is underground. In the historic building a cascading stair leads down to the wide connecting hallway, where already visitors can enjoy artwork on view. All the levels in the extension are linked via a broad two-flight stairway. The foyer and the delivery area for artworks are set on the ground floor. The collection is housed in rooms on the first floor and the lower level, while the second story accommodates temporary exhibitions.
The arrangement of the floor plan is based on rectangular exhibition rooms. The complex spaces set between them - including the foyer and the linking hallway - offer circulation routes as well as setting the tone and providing areas for art education activities. They punctuate the tour with vistas to the outdoors and also give visitors a chance to pause between rooms. On each floor there are several circuits through the exhibition rooms, which are sequenced by the interposed circulation spaces.
The exhibition rooms on the second floor enjoy natural light from above via a light-diffusing glass ceiling. The skylight superstructure above this captures the daylight through a glass roof equipped with etched panels and shaderoviding photovoltaic units arranged in a grid. On the first floor the rooms that house the collection are illuminated via a lateral skylight. The foyer faces onto the surroundings with large windows.
The building is constructed of concrete and steel components. The load-bearing concept is based on a cross-wall structure with the interaction of walls and ceilings. The surfaces in the intermediate zones and stairways, as well as the façades, are executed in beige limestone concrete. The façades are composed of different cast concrete ‘framing elements,’ set one above another, some flush with the surface and some recessed.