Centurion House, Buildings 21 and 21a (Dining Room and Institute)

Centurion House, Buildings 21 and 21A, also known as the Airmen's dining room and institute, was built between 1936 and 1937. The architectural advisor was A Bulloch, who worked for the Air Ministry's Directorate of Works and Buildings. The building features cavity brick construction and has interlocking tile roofs with parapetted hipped roofs and brick stacks.

The layout consists of two parallel blocks situated to the north and south of a central service yard. The exterior is two storeys high, with all windows being wood sashes set in flush boxes, featuring brick voussoir heads and concrete sills. The south block has an eleven-window elevation, with twenty-pane sashes on the first floor and twenty-four-pane sashes on the ground floor, along with a projecting central bay that has a hipped parapetted roof. Above the panelled double doors, there is an eighteen-pane sash set in a semi-circular header arch with imposts and a radial fanlight. There are one-window returns to the right with a similar doorway, and the door surrounds have channelled rustication. The rear wings have similar window designs.

The north block has a fifteen-window elevation with similar fenestration and a central parapetted entrance porch. The outer bays feature hipped roofs that extend to the eaves below the central parapet, and there is a fifteen-pane sash above a semi-circular arched doorway with a radial fanlight.

Inside, there is some internal joinery, including panelled doors and staircases with steel balustrades.

Historically, this building represents a distinctive design from 1935 by architect A Bulloch. The detailing is restrained, but the massing, spacing, and proportions are carefully considered in a neo-Georgian style, influenced by the Royal Fine Arts Commission and architect Sir Edwin Lutyens. Manby is noted for being one of the most complete and architecturally unified of the post-1934 RAF stations from the Expansion Period, alongside Hullavington in Wiltshire.