Tropical Biome, Leipzig

The tropical biome brings species of flora and fauna together that where separated by the splitting of the Gondwana continent and exhibits them side by side that one can see how various plants and animals developed differently after the separation into the modern continents of south America, Africa, and India.
The project accommodates 400 animals of 45 different species and 17.000 exotic plants in a rain-forest climate. Visitors travel through this landscape by automated boat or through a suspended network of rope bridges above, thereby providing a subtle separation between the animals and the visitor. The main hall extends to 1.65 hectares.
The roof form is a section of a sphere; this refers to the scale of the Gondwanaland theme but also allows a significant building volume and height (38 metres in the centre) to respond to the adjacent urban context by dropping to 7.5 metres at the corners. The roof form is an economical filigree shell structure constructed of round hollow sections 80 cm deep of various wall thicknesses, achieving a clear span of 160 metres.

Each knuckle joins six tubes of various lengths with exact the same geometry. Suspended from this is a secondary structure of 411 triple-layer ETFE cushions under constant pressure. In this warm and windless environment the plants will grow up to 2 metres.
While significant temperature variation can be accommodated the humidity must be maintained between 70% and 100%. In summer months, temperatures rise quickly under the lens of the roof. This is managed by opening sections in the roof to generate cross ventilation.
The new hall can be entered from within the Zoo or a new public entrance from the Pfaffendorferstrasse. The new entrance forecourt provides the public with a panoramic preview of the hall where new additions to the zoo population can also be displayed.