A composition of three parts with different finishes to each. The rectangular stone volume faces the residential neighbourhood and rises to a height of 150 meters (492 feet). This was the limiting height for tall buildings until 1989 and is clearly marked as an urban datum on Frankfurt’s skyline.
The second volume is curved and rendered in glass. It is terminated by a projecting cornice-fan which is intended to magnify the spatial quality of this gesture and also to convey a sense of “roof” to the plaza below. The steel cornice-fan on top of the building weighs 95 tons and is heated in winter to avoid icing – as this would be particularly dangerous to traffic beneath due to the size of the overhang.