Municipal Administration

The new municipal administration of Etterbeek is the largest passive building in Brussels. It accommodates public services, the police force and the public social services centre (CPAS/OCMW). The project also includes a 5,100 m² apartment building on six levels. With a net surface area of 14,500 m², the administrative centre is distributed over six levels. Slab support columns were removed in two places in the building to meet architectural requirements. This modification created significant cantilever areas with consequences for the stability and structure of the building. On the ground floor, the entrance canopy does not feature any columns along the whole curved section. The overhang thus created is supported by vertical metal columns to distribute the horizontal loads. At the foot of these columns, 35 m long oblique metal tie rods go further into the concrete slabs of the two upper levels to distribute the loads in the other compression screeds. Where the wedding hall is located on the second floor, the architects wanted to free up the space by removing as many columns as possible. It was necessary to redistribute the loads through the two upper levels and hang the whole structure from a huge 4.5 m high truss on the 6th and last floor. The structure was then tensioned with jacks. 

Slat and panel cladding in Ultra High-Performance Fibre-Reinforced Concrete (UHPFRC) was used for the façade. The challenge was to secure these offset elements on to the passive building envelope.