The office building of the Raiffeisenbank im Rheintal - after its recent extension and renovation - is now one of the most significant buildings situated in the center of Dornbirn (Province of Vorarlberg, Austria). Great efforts have been made to transform the existing building into a contemporary and unique HQ for one of the largest banking companies in Vorarlberg.
The bank started business at this place in 1956, when the initial building was built. In 1973 the first extension took place. The floor area increased by more than double and an additional floor led to a new volumetric appearance and redesign of the existing building. Further office space was needed in 1990, when the building was again extended by an annexe, situated in the western part of the plot.
In 2008 the board of directors drafted the idea of extending the building one more time. A top floor should accomodate functions like in-house education and events, as well as a informal meeting place for the staff. A competition was held and the brief not only asked for this specific extension, but for a redesign of the building's appearance itself. This was driven by the fact that all windows, as well as the thermal insulation in general, no longer met the requirements of todays building standards and therefore needed to be replaced.
After 14 months of renovation the appearance of the building has totally changed. Extended with a sixth floor and entirely covered with sheets of perforated aluminium, the 'new' Headquarter Building is a unique landmark in the city of Dornbirn. The facades facing east and south are equipped with a project specific sun-shading system. Aluminium cladded frames, rotating about their eccentric vertical axes, track the progress of the sun. When exposed to sunlight, the building alters every 12 minutes its apperance. Under full sun exposure the frames are rotated in a position parallel to the facade, giving the building volume a planar apperance.
For the rest of the time, the frames rotate forth or back until they reach a position of 90 degrees in alignment with the facade. This is done automatically, but users can intervene and adjust the position of the shading frames in order to suit their personal requirements. From the outside the perforated aluminium sheets look opaque, but from the inside, due to the chosen grid of the perforation, the they appear like a soft curtain, allowing a undisrupted view to the outside.