Designed for the Braun company, this three-storey U-shaped office building encloses a courtyard on three sides. On the fourth side is a covered entrance area. The most striking feature of the complex is the functionally and aesthetically unusual facade system, which was specially developed for this project and which the architects regard as a technical interpretation of the Swiss box window. To avoid overheating internally, the electronically operated room-height casements in the outer skin can be opened outwards. The windows in the inner skin may be opened manually for ventilation purposes. The appearance of the building is transformed by the opening of the outer windows from a smooth, reflecting cubic volume to a transparent, animated form. (Andrea Wiegelmann)