21 Clarendon St., Londonderry

21 Clarendon Street, Londonderry

A mid-Victorian mid-terrace townhouse of two bays and three storeys with an attic, built around 1874. It is rectangular on plan with a projecting rear return. The building is one of three distinctive properties (numbers 17, 19 and 21) that were the last to be constructed in this terrace of twelve predominantly brick-faced townhouses.

The principal elevation faces north, set behind a low rendered boundary wall topped with replacement metal railings. A single red brick chimneystack rises from the west side, centred on the ridge and topped with nine octagonal clay pots.

The front elevation features painted render to the ground floor and red Flemish bond brick to the upper floors, with a rendered band at the eaves. All windows are timber sliding sash (1/1 pattern) unless otherwise noted. Those to the ground floor are square-headed, while those to the upper floors have segmental-arched heads.

The entrance doorway is positioned to the left and is square-headed, surmounted by a projecting moulded cornice supported by a pair of painted pilasters with console brackets featuring acanthus leaf detail on either side. The doorway is formed by paired half-leaf two-panelled painted timber doors with a single-pane square-headed overlight. To the right of the door is a single tripartite timber sliding sash window (1/1, 1/1, 1/1 pattern), also surmounted by a hood mould supported by four console brackets with painted acanthus leaf detail. Two further windows light the first and second floors; those to the upper floors are not aligned with the ground floor openings. First floor windows have a continuous sill course and painted moulded surrounds with keystone detail. Second floor windows have painted moulded surrounds. A pitched slated roof dormer to the attic level contains a painted casement window with top-hung opening lights.

The east and west elevations are abutted by adjoining buildings (numbers 19 and 23 Clarendon Street respectively).

The south (rear) elevation is cement rendered across three storeys with attic. A cement rendered four-storey rear return extends to the right with a pitched roof. The fenestration pattern to the rear is irregular, comprising a selection of casements and timber sliding sash windows (1/1 and 2/2 patterns). Ground floor windows are obscured by metal grills. The rear elevation was not fully visible at the time of survey.

Two 1/1 timber sliding sash windows light the ground floor of the main rear elevation; a single 1/1 timber sliding sash window serves the first and second floors to the left. A pitched roof dormer to the left contains a casement window. The rear return's south gable has an irregular fenestration pattern: a single window opening to the left at ground floor, abutted to the right by a single-storey pitched roof building with a blank south gable and east face. The west face of this building comprises a window opening to the right and a door opening to the left. A single central 2/2 timber sliding sash window lights the first floor of the rear return; a single diminutive 1/1 timber sliding sash window serves the second floor to the right, with its right reveal aligned to that of the window below. A top-hung casement window serves the third floor to the right. The east face is abutted by the return of number 19 Clarendon Street; the west face was not visible at the time of survey.

The building is located within the Clarendon Street Conservation Area. Roofing is natural slate with cast iron rainwater goods. Walling materials comprise rendered surfaces and brick, with timber windows throughout.