Soane presented proposals to William Pitt on 23 and 29 July 1799. Drawings 29 was presented to Mr Pitt on the 29^th and drawing 30 shows the revised plan with amendments included to have, for example, a common staircase, a working room, a copper in the scullery and a stove in the entrance hall. The doors and windows are also centred and slightly repositioned. The entrance hall has eight columns supporting an oval ceiling. The office wing included in rough pen on drawing 29, with laundry, court and servants hall, is still a preliminary design on drawing 30. The house measures 89 feet 9 inches by 71 feet 8 inches.

Rough plans in pencil on drawing 30 show an alternative design for the principal staircase, starting in one flight to a half landing and returning in two quarter-turn stairs with landings.