A curved building element (1) for a ceiling structure, the curved building element comprising at least one curved reinforcing device (6) which is attached to fixing devices (10) at headers (7), and the curved building element (1) also comprising at least one reinforcing device (8) which is attached to fixing devices (9) at headers (7), characterized in that the curved reinforcing device (6) is fixed to the external side of the curved deck (4) in the longitudinal direction of the curved building element (1) by friction devices (13), and that the curved reinforcing device (6) is fixed to a curved fixing device (10) which in turn is attached to transverse elements at each longitudinal end of the curved building element (1); that the curved building element comprises at least one side element (2) which includes longitudinal braces (3) that are placed on the same side of the side elements (2) and oriented towards each other on the curved building element (1) and fixed to the curved deck (4) and transverse elements (7) at each longitudinal end.