For decades, Belval in the north-east of Esch-sur-Alzette was known as the “The Ruhr” of Luxembourg. And just like in the Ruhr area of Germany, there have not been any smoking chimneys in the “beautiful valley” (translation of “Belval”) for a long time. The production of pig iron in Luxembourg came to an end in 1997 with the decommissioning of the last blast furnace. This decisive point also marks the beginning of a large-scale urban development project. Based on the master plan by Dutch architectural practice Jo Coenen, a new district including residential homes, workplaces, a university and research facilities has been created on the approx. 120 hectares of wasteland. As the industrial plants were to become a part of this urban environment, the two remaining blast furnaces A and B (a third was dismantled and sold) and other buildings on the former site of the blast furnaces were incorporated into the urban development concept.  

Heritage status protects the existing buildings 

One of these buildings is the “Möllerei”. Coke and iron ore, (the “Möller”), used to be mixed and stored here. Built in 1910 and modernised at the end of the 1960s, the building is 164 metres long, 25 metres wide and approximately 26 metres high. In 2000, this huge hall situated at the foot of the blast furnaces was entered in the “Supplementary List of National Monuments”; which was accompanied by an obligation to preserve it. Its conversion was completed in two construction stages: The northern section of the building which spans a length of around 110 metres has been used as a university library (Luxembourg Learning Centre) since September 2018. The remaining third of the Möllerei was then converted into an event and exhibition hall under the direction of the architectural practice BFF architecture & urbanisme, Luxembourg, in a further construction phase between March 2020 and February 2022.  

Structural reinforcement and appropriate standards of energy efficiency 

The priority of the renovation and conversion of the Möllerei was to preserve the building as it was in 1970. It was with this in mind that the corroded metal cladding of the façade was replaced with new sheet metal panels and the roof was also updated. However, a deliberate decision was made not to upgrade the thermal insulation to today’s energy efficiency standards: “The decision was made at the time that we would protect the building against external weather influences, but that indoor temperatures between 12 and 15 degrees would be sufficient for the use of the events and exhibition space,” explains Julia Nockemann from architectural practice BFF. “The client also wanted to keep the ribbon window as visually unchanged as possible.” As the heritage preservation authorities valued the preservation of the external appearance more highly than the energy-efficient refurbishment, the ribbon windows of the two long façades and the gable façade were ultimately renovated using the non-insulated Jansen Economy 50 steel profile system. In keeping with the industrial character of the building, the heating system was also reduced to a minimum. This does not, however, rule out the hosting of events in winter, as the areas designated for events have all been constructed using thermally insulated profiles. Included in this in particular is the new entrance area with its adjacent foyer. Here, the thermally insulated Jansen VISS mullion/transom façade system was used, which enables especially elegant façades to be created. The entrance doors themselves were fabricated from the Janisol steel system, which is also thermally insulated.  

The conversion requires new access 

The conversion of the “Möllerei” into a publicly accessible location also called for some structural adaptations which went beyond the structural reinforcement of and renovations to the existing building. Amongst other things, a new staircase with a lift was added along with ramps and bars, which make it possible for visitors to walk around the industrial monument. Since the completion of the renovation work, the functioning of blast furnace A has been documented here across nearly 400 square meters using digital and interactive installations. While this was conserved in its entirety due to its excellent condition, only the shell of blast furnace B was preserved. This iconic industrial monument commemorates the significance of the iron and steel industry during the 19th and 20th centuries. 

Project details: 
Client: Fonds Belval 
Architect: BFF architecture & urbanisme, Luxembourg 
Metal fabricator: Lefevre Lux S.a.r.l., Bascharage 
Steel profile systems used: Economy 50 fixed glazing, Janisol 2 doors, Janisol doors, VISS façade 
System supplier: Schüco Jansen Steel Systems, Bielefeld 
System manufacturer: Jansen AG, Oberriet/CH