The dining room would have been located at the back, on the first storey of the house.

It is not known if this design was executed as there is no known photographic record of the chimneypiece prior to demolition.

This design makes use of the same stiles as a chimneypiece designed by Adam in c1767 for the great dining room at Fort George. The Fort George design is inscribed in pencil with the words, 11t House / Parlor / Back Parlor, suggesting that Adam had considered reusing it at the Adelphi, although he had perhaps originally intended it for another room in another house at the Adelphi.