Built entirely in sandstone, the college is 14th century English Gothic in style, and substantially Renaissance Baroque in plan, in the manner of Wardell's earlier monasteries and convents. The principal floor or "piano nobile" is above the ground floor and is related to a central space (the ante-chapel) by a series of classical enfilades. The arrangement of the ground floor entry vestibule, and the formal, axially linked Imperial staircase are equally classical in inspiration. In this respect St John's is unlike the traditional layout of an English university college. The formal parts of the building are very grand, particularly if compared to the almost domestic scale of Blacket's contemporary St Paul's College.