Unver, first of all, thank you for your comment. * Since the roof will sit on the mahvil floor ceiling, I did not enter a live load. *I missed the loads on the mahvil floor ceiling beams, I rearranged them and entered 0. *I entered the stair load as 1 tf/m2 live load on the beams around the stairs. Is it missing or wrong? *As you said, the length of the reinforcement exceeds 12 meters. When I get the beam extension, I will manually arrange the reinforcement overlays in 2 dimensions. Do you think it would be economical to carry the roof on the cassette floor and the wooden ceiling covering from the bottom? Do you have any suggestions about the design?