Based on a former urban analysis, the concept for the expansion of the art museum follows the historic development of the city Celle. According to the importance of the museum, another independent volume is added to the palace square, constructed from modern materials. It does not perceive itself as a solitaire, yet creates relations to the surrounding ensemble as the Bormann Museum including its extension from the 1990s.
The cube, measuring 10x10x10 meters, takes on the heights and spaces of the building ensemble. The design of the façade does not try to continue the existing architectural elements, but reduces the materials used and creates an exciting tension between old and new. Evenly reflecting glass surfaces – precise and without any special retaining strips, visual attachments or sheet metal coverings – let the surrounding area reflect in the dependence of light and weather conditions. The connectional structure consists of surface, line and volume.
The three meter high glazing, lining up with the street level and covering the entire cube opens up the entrance towards the street corresponding and contrasting with the sand stone base of the neighboring old building. At the building corner towards the neighboring house, the openings on top of the cube were replaced with clear glass, offering the views towards the castle and thus stages the spatial narrowness between the extension and the old building.
The entire façade was realized bivalve. In the dark, the surface is backlit in white. LED lights allow for a computer-controlled light animation within the entire color spectrum. On special occasions, like exhibition openings or city festivals, the cube can be staged in different color shades and arrangements.