A public sports hall in Zagreb — its roof structure built on the logic of the children’s game „stolček".
The hall draws its structural idea from a children’s game called „stolček": two people face each other, each grips the other’s opposite wrist, and their hands form a square that carries a third person. What results is a load-bearing system where neither of the two can carry the third without the other.
That same logic shapes the hall’s timber roof: twelve beams stacked so no single beam can stand without its neighbour. The beams spiral around the centre of the hall, suggesting motion — like a gymnast on a pommel horse.
Because the geometry generates large horizontal forces, diagonal struts run down to the foundations, forming triangles that give rhythm to the façade. Structure alone unifies roof and envelope, resolving elevations, statics and composition in a single move.
