Antonio da Sangallo (known as "Sangallo the Younger") looked at all the different plans by Peruzzi, Raphael and Bramante. He put some of their ideas together in a design that had a very short nave, (not a long one like Raphael's design) and had a big porch at the front. He changed Bramante's dome to be much stronger and also much more decorated. The main new idea that he added were 16 stone ribs to strengthen the dome. This idea came from Florence Cathedral which had eight stone ribs. But Sangallo's plan never got built, either. The main job that he did was to strengthen Bramante's piers which had begun to crack.