Since 2006, the administrative centre of the federal authorities in Ittigen has housed agencies of the Swiss Confederation, namely the departments of environment, traffic, energy, and communications. In an open competition for a two-stage expansion by 900 workstations, the jury chose the proposal by Berrel Kräutler Architekten. The existing complex is being extended with logical consistency via a pair of elongated, compact buildings having the same alignment. Emerging is a vibrant campus with rhythmically staggered open areas and pathways. By 2020, the first building was finished, and it is now occupied.
In plan and section, the new seven-story building is clearly structured volumetrically. Configured around a central concrete core are circumferential stories consisting of a composite wood-concrete construction. Found at the building’s heart is an astonishing spatial sculpture, an atrium framed by two curving staircases. Interfused by a number of massive elements, it nonetheless allows sunlight to reach the ground floor. This enthralling interior, with its varied views, reflects a spirit of exchange and community. Found here are conference rooms and lounges.
The single and open plan offices are strung along the façade; their spatial and technical flexibility allows them to be partitioned as needed. They offer superb views and optimal lighting and ventilation, and moreover a warm atmosphere generated by the use of wood and wool carpeting. The façade has vertical wooden slats and projecting parapet strips, integrating the building in the existing campus. The thicknesses of the slats increases as they ascend, reducing the amount of glazing where more daylight enters.
Existing landscape elements were taken up and developed in conjunction with the designs for the other areas of the new buildings. Arising along the banks of the Worble River is a spacious landscaped zone whose vegetation is typical of floodplain meadows. On the hillside, walking trails leading through the woods have been upgraded, and shadowed areas installed for rest and relaxation. Where autos were formerly parked between buildings, framed squares with groves of trees and outdoor furniture encourage users to linger. The footprint of the future second building is now a temporary park with dense shrubbery and benches. A variety of open air spaces offers a stimulating experience of the natural environment.
The ingenious combination of wood and concrete is innovative for sustainable design. The use of local wood improves ecological balance and ensures a pleasant indoor climate. Its minimal mass reduces the impact of earthquakes. The concrete achieves horizontal and vertical stiffness, and its storage capacity is beneficial for energy requirements. To conserve resources, energy is provided by exhaust heat from a nearby computing centre and by solar technology, and cooling by using spring water. The building received the Gold Certificate from the Standard for Sustainable Building in Switzerland (SNBS).