A student of Frei Otto, who produced the astonishing Munich Olympic Stadium roof, architect Thomas Herzog designed these stylish timber shells to shelter temporary displays at the World Expo 2000 in Hannover, Germany. Architect Penny Richards describes what's going on:
The canopy comprises 10 modular elements, each one measuring 40m x 40m, at a height of 20m above ground level. The elements are timber double-curved lattice shells, each supported on a central structure.
The roof shells cantilever out on all sides looking like giant whale tails. The shells are covered by a pre-stressed translucent membrane and the rainwater is collected and brought to the ground through each of the central structural supports. These supports are each cut from a single tree trunk, from the classic Silver Fir, of the Black Forest. Seventy trees 50m tall were selected. The bark was stripped with high-pressure water jets and the trunks were cut in half lengthwise, to form each of the four corner columns.
This elegant but robust canopy is a demonstration of a tree reborn from the forest to the structure. The columns represent the simple vertical structure of the tree, and the filigree lattice shells represent the tree canopy. The timber lattice allows daylight to penetrate below, just as it does in the forest.