Drawings 151 and 152 are some of the first of the Pitzhanger designs to focus on the layout of the offices. Drawing 151 shows the entire house, but the office wing and stables are the only parts that are labelled and have clearly been reworked in Soane's hand. The offices, entered via a courtyard off the main house, include a long gallery for plaster casts.

Drawing 152 focuses completely on the offices, showing a different layout of rooms to drawing 151 and a rectangular room for plaster casts instead of a long gallery. A room for plaster casts had its origin in some of the designs for a villa at Acton, and such a room was eventually built at Pitzhanger. Virginia Brilliant's TS catalogue suggests that this room was to function as a display room for objects 'found' in the adjacent 'ruins'.