Swiss Federal Institute of Aquatic Science and Technology Celebrate the Opening of Forum Chriesbach

Eawag – the Swiss Federal Institute of Aquatic Science and Technology – is celebrating the opening of Forum Chriesbach, its new headquarters in Dübendorf. Construction work, including site landscaping, has been completed at a cost of around € 18.7 million (credit approved: € 20.7 million). The building, designed by the architectural firm Bob Gysin + Partner, accommodates 150 office workplaces, together with training facilities and meeting rooms, and also houses the joint Empa Eawag library and the staff canteen “aQa”. With a facade consisting of 1232 adjustable blue glass fins on all five storeys, the building is an eye-catching structure. The atrium of the reinforced concrete skeleton construction also gives the interior a striking appearance, with clearly defined and spacious forms. Above all, however, the latest requirements for sustainable development in construction are met by Forum Chriesbach in a consistent and integrated manner. The clients’ courage in defining these specifications has been rewarded.

• Excellent insulation, the heat- and cold-storing capacity of the floors and access cores, and sophisticated ventilation make conventional heating and air-conditioning systems unnecessary. - In the summer, all the rooms are cooled overnight by the automatic opening of vents (via the atrium roof), and during the day pre-cooled air is supplied from the earth-to-air heat exchanger this ensured pleasant working temperatures even during the lengthy July heatwave. Only the lecture theatres and meeting rooms are equipped with cooling ceilings, to absorb the heat generated when these rooms are occupied. - In the winter, heating requirements are met by the recovery of waste heat from the building (from people, computer systems, lighting, canteen kitchen, exhaust air, etc.) and with pre-heated air from the earth-to-air heat exchanger. In the event of very cold temperatures, heat can be obtained from the Empa-Eawag network. It has been calculated that the equivalent of 2350 litres of heating oil will be sufficient to ensure these external supplies – less than the amount required in many detached houses.

• The building’s aesthetic character is shaped by the glass fins in front of the fire-escape balconies. These fins are adjusted according to the position of the sun, so that the offices are not heated up by direct exposure to sunlight in the summer; in cold weather, however, the sun’s rays are allowed to pass through.

• On the flat roof, solar energy is actively harnessed – with vacuum tube collectors (50 m2) for hot water and a photovoltaic system (459 m2) which produces around a third of the electricity required in the building.

• Rainwater retained by the extensive roof vegetation is collected in a reservoir to be used for toilet flushing. Urine is drained separately from all the toilets. Eawag is using its own building to research and optimize separation (NoMix) technologies for urban water management.

• The surroundings have been landscaped along near-natural lines, integrating the Chriesbach river. In cooperation with the Canton Zurich authorities, a study is being carried out to determine how this section of the heavily engineered watercourse can be rehabilitated. It would thus be enhanced to provide a habitat for aquatic organisms and a recreation area for local residents and staff, as well as being used by Eawag for research and demonstration purposes.

• The staff canteen “aQa”, which serves organic, seasonal dishes, has been awarded the “Goût Mieux” label.

• All the materials used were assessed for environmental soundness and effects on human health. Close attention was paid to the careful management of resources and to the facilitation of recycling and disposal in the event of dismantling. Recycled concrete was used for the ceilings. The office partitions are made of wood, clay and reeds, and thus help to regulate interior humidity. An assessment of all the materials used indicates that in a building of this kind “grey energy” is an increasingly important factor. In an old building, energy savings can be achieved for example by improving insulation; in the case of Forum Chriesbach, however, the building and its operation are optimally matched. The energy embedded in the building (43,000 GJ/12,000 MWh), on an annualized basis, yields an energy consumption roughly equivalent to the amount of energy required annually to operate the building (assuming a lifetime of 38 years for the building).
   

• In the Forum Chriesbach project, all the parties involved have approached the limits of what is currently feasible. This pioneering achievement is based not only on the individual measures implemented, but especially on the optimized interaction of all the various elements and the close dialogue among all parties throughout the construction process. The insight gained from Eawag and Empa’s own research – that there is an urgent need to promote sustainable development – has been put into practice on the institutes’ home ground.

• Clients: Eawag and Empa, represented by Research Facilities (BaFA)
• Architect: Bob Gysin + Partner BGP, Zurich
• General contractor: Implenia Generalunternehmung AG, Dietlikon