The project includes a comprehensive restoration of the old hothouse in the Botanic Garden in Aarhus originally designed by C. F. Møller Architects. In the restoration the palm house will become a new botanical knowledge centre, at the same time as the complex is extended with a new, 18 metres high tropical hothouse, in which the public can go exploring among the tree-tops. The existing snail-shaped hothouse was well adapted to its surroundings, and it has been important to bear the existing architectural values in mind when designing the new one. The new hothouse also uses the organic form, which is, at the same time, based on energy-conserving design solutions and on a knowledge of materials, indoor climate and technology. Advanced calculations have ensured that form and energy consumption interact in the best possible manner. The domed shape and the building's orientation in relation to the points of the compass have been chosen because this precise format gives the smallest surface area coupled with the largest volume, as well as the best possible sunlight incidence in winter, and the least possible in summer.