Its exterior is unadorned by architectural or decorative details, as is common in many Italian churches of the Medieval and Renaissance eras. It has no exterior façade or exterior processional doorways, as the ingress has always been from internal rooms within the Apostolic Palace (Papal Palace), and the exterior can be seen only from nearby windows and light-wells in the palace. Subsidence and cracking of masonry such as must also have affected the Cappella Maggiore has necessitated the building of very large buttresses to brace the exterior walls. The accretion of other buildings has further altered the exterior appearance of the chapel.