On a small site close to the centre of Brussels, Bogdan & Van Broeck architects elegantly stack a sports hall, a multipurpose hall, a cafeteria, spaces for a boxing club, a day-care centre and a caretaker’s dwelling. The most public functions are located at the bottom, the most sheltered ones above. The Brussels-based office designed the project around three open spaces that connect the various functions: a covered public passage, “the Gallery”, a central patio, “the Patio”, and “the Hanging Gardens”. Three parallel concrete walls (two of which are party walls) start at basement level and run up to the first floor. Two of them form the basis of the load-bearing structure and accommodate the sports hall, multipurpose spaces, cafeteria and boxing club. The inner wall is cut with large round arches to ensure circulation and visual continuity within the building. To achieve the large spans required by these open spaces, four double-height steel truss girders (21 m long and 7 m high) were installed perpendicular to the concrete walls and anchored to them. The day-care centre and the caretaker’s dwelling, located on the second and third floors, are built in between and suspended from the truss girders. The long prestressed TT beams forming the ceiling of the sports hall are also attached to them. Three concrete cores reinforce the whole structure. The truss girders were fabricated as single elements in the workshop and transported to the site by barge; thanks to the proximity of the canal, they could be shipped by water all the way into the heart of Brussels.