Drawing 28 is very similar to drawing 27 but with an alternative entrance front, vestibule and corridor. The front elevation has a bowed centre faced with four columns and flanked by two bays on both sides. The building measures 95 feet 9 inches by 66 feet 9 inches. The main corridor is a series of arches, an effect Soane later expanded upon at the Bank of England Waiting Room Court, 1803 (q.v.) and at Wotton House, c. 1822. Apsidal niches in the corridor have pedestals, probably intended for exhibiting statues.

The presentation drawing has been altered in black and red pen by Soane to show the dimensions of the attached pilasters at the corners of the building, and the floor levels of each storey. The ground floor is to be raised 6 feet above ground level, and the basement is to be 4 feet 6 inches below ground.