Laboratory Cottages

Laboratory cottages designed by Colonel Lewis, Commanding Royal Engineer of the Portsmouth District, were constructed in 1847, with alterations made in 1877 and the roof replaced in 1892. The buildings are a long, narrow hipped range with a smaller hipped wing at the rear. They are built of brick in Flemish bond, with slate roofs on timber trusses, which replaced the original flat roof.

The front has two groups of three 12-pane sash windows with rubbed brick voussoir heads and stone sills. Between these groupings are two framed plank doors leading to a stone step. To the right, the window arrangement has been altered; there are now three small square lights under a concrete lintel, a four-panelled door with a three-pane overlight, and a door flanked by modified sash windows. The rear elevation retains good 12-pane sashes to the right of the projecting wing, which has a single sash window. Windows to the left have been modified.

Internally, the buildings were originally divided into three cottages, each with a small single-room rear wing. Fireplaces and stacks were removed during the 1877 alterations.

Historically, the cottages were designed with flat roofs, contemporaneous with the nearby Laboratory buildings. The two left-hand units remain largely unchanged externally. They are of group value as the only surviving accommodation of this type at any of the ordnance depots. The later conversion to a tube and rocket store in 1877, and enlargement in 1892, reflect the site’s historical importance and its evolution to process new naval ordnance in the 19th century. The magazines and structures at Priddy’s Hard date from the late 18th century, with expansion closely tied to the development of land and sea artillery and the navy’s transition to new technologies. The site demonstrates Britain's rise to global sea power. Further historical details can be found in the description for ‘A’ Magazine.