When it comes to building construction, Minergie-P-Eco, Standard Nachhaltiges Bauen Schweiz (SNBS) and 2000-Watt-Areale are already well-known standards. However, the new building in Chur with the title FAR (Rhaeto-Romanic for lighthouse) goes one step further. The lighthouse project is characterised by ideas of resource conservation and sufficiency. Under the lead of G+P as sustainability planner, the net-zero goal is the target. The entire life cycle of the building is considered, from project planning to construction, management and even demolition – hopefully a long time in the future.
An innovative project by renewing proven ideas and technology
The building was designed by the award-winning architects "Comamala Ismail Architectes". It is the new construction of an administrative building, which will be used in future as a traffic base for the Graubünden cantonal police. The application of well-tried principles for sustainable building is obvious: compact volume, reduced construction as well as clear, simple structures and flexibility. But net zero demands even more, which is why G+P was brought on board. Through the choice of building materials and optimisation of components, the aim is to conserve resources and reduce the environmental impact as much as possible. At the same time, however, all aspects of architecture and all specialist planners in the planning team are to be considered without losing sight of the legal and normative requirements.
The following points make this building unique:
- All load-bearing components are made of recycled concrete. The excavated material is directly reused and, if possible, processed to produce concrete in the concrete plant located within walking distance.
- The façades not only provide heat, sun and weather protection, but also serve to produce electricity. For example, projecting photovoltaic modules on the parapets, inclined at 45°, will produce a significant proportion of the operating energy, including a surplus.
- The entire new building will be a solid hybrid construction. Materials and systems that are incompatible with sustainable construction are consistently not used. These include, for example, biocides or wood preservatives as well as harmful adhesives in interior spaces.
- All non-load-bearing walls are constructed in clay building boards.
- Material consumption is reduced to what is sensible and useful. For example, subfloors or suspended ceilings as well as plaster, facing shells and paint coats are avoided as far as possible.
- Furthermore, materials and components are used that were once installed in another building (e.g. windows from a demolished building). This kind of reuse of resources should also be possible in the future in the event of a possible decommission - a circular economy entirely in the spirit of G+P.
Microclimate and biodiversity
The generous surrounding area offers space for unsealed surfaces with different plantings of native species. This environmental design avoids heated asphalt and façade surfaces as well as a lack of shaded areas. With such simple measures, a pleasant microclimate can be created for the users.
Moderate also in building technology
With the focus on the envisaged net-zero target, the energy concept was planned early on. Connecting the building to the CO2-neutral, local energy grid was already an option in the very first planning phases. Conservation of resources and simplicity here too. Using a heat pump, the ceilings are heated as thermo-active building systems (TABS) and cooled only where really necessary. Sufficiency is the watchword. All rooms are mechanically ventilated to a minimum. Ventilation fans can also be used for night cooling, which is intended to prevent active cooling by means of a heat pump. The calculations prove that the photovoltaic systems on the roof and the façade supply more than enough electricity for the building services, the offices and the operating areas. Surplus electricity is stored in batteries and the hot-water tank; this can be used to bridge the electricity demand on bad-weather days. In the future, it can also be used to charge battery-powered vehicles by feeding it back into the grid. The technical wiring for electricity and ventilation is visible.
With the planning team on the cutting edge
The project is planned and implemented using the full BIM method. This includes, on the one hand, the creation of coordinated digital models of the structure and, on the other hand, the design of transparent and interdisciplinary planning and operating processes. The BIM method is not only used for construction planning, but also for calculating processes during operation. G+P offers its services and carries out various calculations with BIM. Energy considerations and verifications, the calculation of so-called grey energy or simulations of room temperatures or room air hygiene over the course of the year can be carried out at the push of a button.
On the way to Switzerland 2.0
FAR is the answer to the risks of climate change and will serve as an illustrative object and at the same time as a basic object for adjustments in the relevant standards and legislation. The experience gained from the project will lead to the development and establishment of a new, future-oriented bestseller competence and provide the basis for possible adjustments to legal foundations and forms of contributions in the building sector. G+P is incredibly proud to be able to play a significant role in shaping this project as a milestone on the path to the built-up Switzerland of the future.