ArchitectEctor Hoogstad architecten
Project size24.000m2 GFA
Start of project2009
Consulting servicesStructural design, detailed design drawings, structural calculations
Several large openings have been made in the first storey’s existing floors. These became financially feasible by making use of the possibilities and capacities of existing floor structures. For example, the large new opening in the central hall is made possible by attaching floor components of the first floor, in which the opening is made, to the second storey’s floor. This required a meticulous calculation of the available carrying capacity. The openings greatly increase the transparency of public spaces on the city hall’s ground level. On the first storey, several meeting spots and a restaurant have been placed around the openings in the storey’s floor.
Such openings have also been designed in the new wedding hall and presentation hall, adding to the allure of these private spaces. Around these spaces, new walking routes have been made possible by adding various stairs and bays in the structural walls.
The new building services called for a larger housing, in both horizontal and vertical dimensions. To this end, the need for a larger shaft and spacing has been optimized, minimizing the impact of this change.
A new entrance to the existing basement was required by the new bicycle parking lot that has been realised in the basement. The space needed for this alongside the retaining basement walls made it necessary to place new floor-bearing walls and rigid floor diaphragms.
On two heads of the office wings, flights of stairs originally starting above the first floor have been extended to ground level, allowing office employees to directly access service desks on ground level without having to cross public spaces.
To accentuate the city hall’s main entrance, it has been provided with a large cantilevering awning. The awning extends to the inside of the building, smoothing the transition between outside and inside. Transparency is ensured by the integration of glass roof plates within the steel structure.
For façade cleansing within the atrium, a new rail track has been laid out, leaving the need for only a minimal amount of structural additions to clean both the inner façade and the atrium’s slanting roof.
Thanks to these changes, the city hall remains a sustainable, spacious, vibrant and accessible city centre for the years to come.