The new multi-purpose building replaces the former “Rail Transport Hall 1”, designed by Otto Dreyer, from the founding years of the Swiss Museum of Transport. The new structure is intended to house several uses, as its name suggests. Like its predecessor, it provides exhibition spaces at ground floor level, now for changing exhibitions alongside the continuing display of rail transport items. Furthermore, the ground floor of the multi-purpose building features a welcoming second entrance area for the museum complex facing Haldenstrasse and the railway station “Verkehrshaus Luzern”, which opened in 2007. Connected to this are also a shop and other entrances for the uses in the upper floors.
On the first floor, three new conference rooms are created as extension of the current conference functions located in the “Futurecom” building. From the foyer the participants have a view into the high exhibition space and also out to the “Arena”. The three floors above are reserved for office use. They are arranged around an elevated green patio and primarily serve the museum administration as well as associated organizations and exhibition partners. The basement not only contains additional utility spaces, but also the new central energy plant of the entire museum complex – a heat pump supplied by lake water.
The new volume is larger than the preceding building and approaches the height of the adjacent existing IMAX movie theatre building. The polygonal plan shape reaches over to the cylinder structure with open air balconies. Together, they form an interstitial space for lighting and logistics. Toward Haldenstrasse, the building cantilevers above a weather protected zone at the entrance and an outside exhibition area. Access for locomotives to the existing “Rail Transport Hall 2&3” stays open.
High structural requirements imposed on the foundation by the difficult substrate as well as the desired column-free exhibition hall with a width of up to 30 m justify the choice of reinforced concrete as building material for the load-bearing construction and the stairway cores. The floor slabs of the offices provide the necessary thermal inertia and accommodate the heating loops of the thermal activated building system (TABS) as well as acoustic absorber elements – thus eliminating the need for further cladding while optimizing the room height. Insulation thickness of up to 30 cm and a moderate proportion of openings with ribbon windows are expected to result in good energy consumption figures. The new building is certified according to Minergie-P.
In analogy to the versatile usage of the building, various and different demands must also be met by the facade envelope. In addition to thermal insulation and summer sun protection, the exterior wall should also be acoustically effective, i.e. dampen reflections of road noise in the direction of the “Arena” and the residential buildings further up the slope. Like most of the buildings in the museum complex, it has a metal facade. In the case of the multi-purpose building, this consists of standardized metal cassettes, such as are frequently used as support structures in industrial construction. The perforated sheet metal, in combination with the insulating layers behind it, meet the mentioned requirements and form the concealing, yet see-through and translucent dress, which also acts as a brise-soleil and, moreover, serves as a support for the photovoltaic elements.
Applying photovoltaics not only on the roof but also on the facades is a challenge for the design and still also for the acceptance. The monocrystalline PV elements are distributed in varying density according to the different exposures of the facades. The arrangement in groups of eight elements, each with a gap, was developed with the artist and geometry engineer Urs Beat Roth. The layout of the panels, superimposed on the ribbon windows and the grid of the metal cassettes, results in a variable interplay. It is an attempt to make the useful energy producers, which are nevertheless often deemed unsightly, an integral part of the façade design, without compromising their efficiency through coatings or custom glazing.