The former administration buildings and assembly halls of General Motors Suisse are located in the Neustadt Süd quarter at Salzhausstrasse 31, near the Biel railway station in the canton of Bern. The sophisticated buildings, which were erected in 1935 and later extended, are considered a pioneering achievement of modern factory construction in Switzerland and are listed as important witnesses to Biel's industrial history. The architect of the avant-garde buildings was the Zurich-based Rudolf Steiger, who thus paved the way for New Building.
Damian Poffet
In the course of the energy renovation, the historic glazing of the north and south facades on the first floor was replaced by a thermally insulated solution with the delicate profile system forster unico xs.
The two column-free assembly halls are designed as steel structures under shed roofs, a type of roof that is mainly used for buildings with a large floor area. Several self-supporting gable roofs are placed next to each other. A special highlight of the halls are the generous glass fronts with fine glazing bars, which allowed a view of the assembly process from the Salzhausstrasse in Biel. From 1955 to 1957, another assembly hall and a spare parts warehouse were built, followed in 1976 by conversion into a multi-storey car park, shopping centre and office building.
See also: Successful refurbishment of a production hall with a luminous facade
Today, the upper floor of the factory building houses a retail space for the furniture store chain Livique. As the first stage of the energy refurbishment of the historic building complex, the fixed glazing of the listed south and north facades of the ensemble were replaced with thermally insulated glazing on the upper floor. Further renovation stages in the same style are to take place in the coming years.
Energy-efficient refurbishment in keeping with the requirements of a listed building
Damian Poffet
The external glass front of the former factory halls consisted of uninsulated single glazing with very narrow profiles. On the north and south facades, a five-metre high and 120-metre wide front had to be removed, the glass elements of which were held in place by steel girders. In total, almost 100 square metres of glazed area with 1,900 fixed glazing units were renewed on the upper floor of the salt house. As the facades are listed, the new fixed glazing had to have the same profile face widths as the original elements made of angle and T steel profiles with single glazing.
The greatest challenge was the triple insulating glazing planned in the course of the renovation - because compared to single glazing, there are restrictions on the maximum deflection of the facade elements under wind loads when using modern insulating glass. In order to be able to meet the static requirements even with the narrow face widths of the profiles, the architects opted for the delicate and robust steel profile system forster unico xs.
The unico xs system is made entirely of recyclable steel and, thanks to its special connection technology, enables very slim profiles with a face width of only 23 mm - something that could not previously be achieved with thermally insulated series. Therefore, the forster unico xs system is ideally suited for renovations of listed industrial halls such as Biel's Salzhaus.
Damian Poffet
Also interesting: Replace old IGU with vacuum glass = less heating!
According to the metal constructor, both the fabrication and the installation of the new glazing were pleasantly quick, so that the tight time frame of only three months could be adhered to. Information on forster unico xs can be found here.
About Forster Profile Systems
Forster Profilsysteme AG develops and produces steel and stainless steel solutions for doors, windows and facades for the contract sector and offers individual advice and on-site project support around the globe.
Accessories and services for customers in architecture, planning and the construction industry round off the portfolio. Forster operates worldwide with its own subsidiaries in more than 20 countries and with sales partners in around 10 others.
