Number 20 And Attached Railings

Number 20 and its attached railings is a former Clerkenwell Parochial School, built in 1828 by William Lovett, with an upper school room added to the rear in 1858 by W.P. Griffith. The front building is constructed of yellow brick in Flemish bond, while the rear school room uses purple and yellow brick, also in Flemish bond, with stucco dressings. The roof is covered in Welsh slate.

The main building is three storeys over a basement, with a three-window facade that is double-fronted. All openings feature gauged brick heads. A segmental-arched entrance is topped by a doorcase of Roman Doric columns, a cornice, and a fanlight with decorative glazing. The original panelled door remains. While the ground floor windows are covered over, the upper sashes are original. A round-arched secondary entrance is positioned on the right-hand side. A twentieth-century stucco fascia sits above the ground floor, with stucco storey bands above the first floor and to the parapet.

The rear school room is two storeys high and has a seven-window arrangement. Its windows have cambered arches, with yellow brick heads and generally original sashes. External steps lead to the upper floor entrance in the seventh bay. A hipped roof is topped with side and end stacks. Cast-iron railings define the area.

The interior of the three-storey front section has a single room's depth across its width. The entrance hall is characterised by a moulded stucco cornice, with panelled panelling extending up the staircase to the first floor. The staircase has turned newels, a closed string, and stick balusters, enclosed on the first flight. Architraves and panelled doors are original throughout the ground and first floors. The left-hand ground-floor room retains a dado rail, panelled dado below the windows, an early nineteenth-century fireplace flanked by bowed fitted cupboards. The first-floor left-hand room also features a dado rail, panelling, a moulded stucco cornice, an early nineteenth-century fireplace with a cast-iron grate surrounded by bowed cupboards, panelled cupboards to a partition wall, and a broad, flat-arched opening with an architrave leading to the upper school room. The first-floor right-hand room has a panelled dado, an early nineteenth-century fireplace, and a bowed corner cupboard. The second-floor right-hand room includes a dado with tongue-and-groove panelling; a left-hand room has an early nineteenth-century fireplace. The lower school room is long and features three wooden columns, square in plan with chamfered and stepped capitals, that support the room above. It contains three early nineteenth-century fireplaces with cast-iron grates and simple wooden surrounds, two to the flank wall and one to the end. The upper school room mirrors the lower room's fireplaces, with a ceiling formed of segmental arches and four metal tie bars, with one exposed beam between the third and fourth bays from the front.