The new headquarters for the European Central bank (ECB), designed by the Coop Himmelb(l)au architectural practice, is under construction on the site of a former wholesale market to the east of Frankfurtâ€™s city centre. Three main elements make up the new premises: twin office towers, an entrance building and the former wholesale market hall itself. The two twisted towers of the high-rise building will add a prominent feature to the Frankfurt skyline. The entrance structure connects the glass twin towers to the refurbished market building, which dates from the 1920s and is now protected by a conservation order.
The external envelope to the 185 m high twin towers is in the form of a â€śshield hybrid faĂ§adeâ€ť â€“ designed, produced and erected by seele. This energy-efficient faĂ§ade is a vital component in the overall energy concept and consists of three-ply prefabricated aluminium elements with electrically operated, room-high, parallel push-out elements in every second bay. These opening lights ventilate the offices directly and naturally; sunshades and anti-glare screens are fitted into the cavity of the faĂ§ade. The shaping of the twin office towers has resulted in sloping faĂ§ade surfaces with a hyperbolic form and scores of different elements. seeleâ€™s skills and experience in the design and construction of highly complex but nevertheless batch-produced building envelopes are indispensable here. CAM, for example, i.e. using data from 3D planning directly for programming and controlling the machining centres for element fabrication.