The Boodschapinstituut in Schaerbeek is equipped with a steel fan canopy on its playground. The fan consists of a series of progressively widening troughs made from folded 5 mm-thick steel plates, each transported individually and bolted together on-site within the restricted-access courtyard. The shape of the troughs ensures that no additional waterproofing layer is required after assembly, while the upturned edges stiffen the panel, allowing the canopy to be realized in very thin steel plates. Further rigidity is provided by two ribs welded into each trough, which, once assembled, zigzag across the surface as two structural beams. The fan is anchored to a wall composed of similar U-shaped elements, which also manage drainage, and rests additionally on two concrete columns. The columns were carefully positioned to optimize the usable space beneath the canopy while accommodating the underlying structural elements of the nursery. Based on these constraints, the rib pattern was finalized.