Former Hospital (Building 42), Hounslow Barracks

The Former Hospital (Building 42) at Hounslow Barracks is a barracks hospital that was later used as a sergeant's mess and is now housing. It was built around 1793 by architect J Johnson for the Barrack Department and underwent alterations between 1920 and 1950. The building is constructed of yellow stock brick and features a hipped slate roof with a single-depth plan.

The exterior consists of three storeys and a five-window range. The symmetrical front has a mid-20th century doorway and door, with inserted windows to the left. The remaining windows have segmental-arched heads and are eight/eight pane horned sashes. On the left side, there is a single-storey lean-to.

The interior was rebuilt around 1930. Historically, this was the original barracks hospital, although it has been significantly altered inside. Hounslow is notable as the only surviving barracks from the first national barrack building campaign in England, which was authorized by Pitt for internal policing of major cities. This hospital is part of the original barracks plan and is one of only three barracks hospitals from this period, alongside those at Higher Barracks in Exeter and Poundbury Barracks in Dorchester. It is included for its historic interest.