Schoolroom Annexe to Kesteven and Sleaford High School

This is a schoolroom annexe, dating from around 1870, and likely designed by Kirk and Parry of Sleaford. It is constructed of coursed squared limestone with ashlar detailing, topped with a slate roof featuring terracotta ridges and finials. The building has a compact L-shaped plan and a gabled porch set on an external angle, exhibiting Gothic Revival details.

The building is single-storey with an attic. Prominent features include large quoins, a chamfered plinth, and a corbelled table at the eaves. The corner porch has moulded plinths with bootscrapers, round columns supporting a moulded basket arch, and a part-glazed door with three panels and three lights behind iron bars. Above the porch is an ashlar oriel window of three lights, alongside shaped kneelers and ashlar copings with a finial. The left return displays three-light and one-light windows with sloping sills, stop-chamfered mullions, and segmentally-arched heads. Original four-pane iron casements remain, featuring central rosettes and pivoting openers. The right return has two-light and tripled two-light windows in a similar style, complemented by decorative cast-iron guttering.

The roof sweeps upwards with lead rolls to hipped ends. A ridge stack on the left return has an offset plinth pierced with a trefoil and two diagonally-set castellated flues, topped with decorative ridge cresting featuring a zoomorphic finial. A two-light window is set into a gabled half-dormer at the end of the right return.

At the rear, a large bay window, possibly reused, incorporates twelve-pane sashes and a French window with transom lights, all beneath a stepped parapet. The interior includes four-panel doors and a corbelled fireplace with brown-marble detailing located in the room with the bay window.

Kirk and Parry, architects based on Jermyn Street, are recorded in directories from the mid-19th century. They were successors to William Kirk of Nottingham, and continued the practice with his son and grandson. The firm also owned a flour mill located off Jermyn Street; this building may have served as their architectural office.