12, St Mary Street

No. 12, St Mary Street is a mid-19th century house, now used as offices. The building is constructed of limestone ashlar with a slate roof and a stone stack to the rear. It has a double-depth plan with a rear wing. The exterior is three storeys high and has a single-window range. A full-height canted bay dominates the right side of the facade, featuring 8/8-pane sash windows on the first and second floors, and a plate-glass sash window on the ground floor. To the left, steps lead to a semicircular arch with a radial fanlight above a 20th-century door. There are blank windows above the door on both floors, and platbands delineate the floors. The interior has not been inspected.