The extension is separated from the old building and fills an area in the backyard of the old building. It is set directly against the surrounding historical buildings and their walls. The hall was constructed in steel as a folded structure and clad with a zinc roof. The resulting building appears self-confident or reserved, depending on the viewing direction. From the museum courtyard, the extension looks like a harmless replica of the existing gable of a neighboring building and is only one element of a series of buildings behind the striking quarry stone wall. Behind it, however, a powerful mountain range of its own geometry unfolds. Inside, the pure space is characterized by the historic quarry stone wall and the folding roof. A glossy, graphic grid was applied to the window area that, depending on the viewing angle, absorbs or reflects the incident light.