A joint work on geometry, structural refinement, innovation in glazing and the definition of climate and light control has developed a unique spatiality, assuring a perfect reading comfort. Elioth ensured the full structural design of this rooflight, isostatically inserted into the existing buidling. The definition of the geometric area was the object of a dedicated mathematical analysis which resulted in a significant outcome for the glazed panels: all resulting glass rhombuses are flat while the overall roof glazed surface is twisted !