Paul Klee Centre in Berne

“The whole attraction of the place lies in the gentle curve of the hill.” The architect’s first impression of the site on the outskirts of Berne led to the design of the new Paul Klee Centre in the form of a landscape sculpture. Three waves rise and fall over a field directly adjoining the cemetery where Klee lies buried. To the east, they merge seamlessly with a field of barley; to the west, they open towards the city. Klee’s daughter-in-law offered to present the city of Berne with 690 paintings, on condition that it build a museum for approximately 4,000 works by the end of 2006. Thanks to donations, it was possible not only to comply with this stipulation, but to extend the spatial programme with an auditorium, a children’s museum and an administrative zone. All functions are linked with each other by a ground floor “museum street”. The geometry of the building comprises a three-dimensionally curved surface based on segments of circles on plan and in both elevations. The load-bearing structure consists of steel ribs cut by computer-controlled oxyacetylene equipment in the many different forms required and then welded together by hand. The depth of these beams varies from 800 to 1,200 mm. Between them is a tubular grille which, in order to achieve a gradual transition to the landscape, gives way at the edges near the ground to sheet-metal trays filled with earth. The support details vary, too. At the front, the wave swings from curve to countercurve, with point bearings at the base. Further back, the curved geometry continues underground, where the reinforced concrete walls of the lower-floor spaces bear the loads. The curved arches are tied with tension cables to the floors. At the highest point, to the west, the roof also bears the loads of the suspended facade. To transmit these over as large an area as possible, a rocker-type system, consisting of steel cables and tubes, distributes the loads over groups of five ribs. Natural light was not required for the auditorium nor for the museum. In the latter, the sensitive quality of the works on display means that a maximum of 50–100 lux is permitted.