23 Kensington Square

23 Kensington Square comprises two distinct architectural components: a pair of town houses built circa 1838 and an adjacent former convent school designed by George Goldie in Gothic style, constructed in phases between 1875 and 1889. The 1929 addition by Joseph Goldie and the 1960s Assembly Hall by C. Lovett Gill are excluded from this listing.

THE FORMER TOWN HOUSES

The town houses date from circa 1838, with the architect or builder currently unknown. Extensions were added to the rear between 1870 and 1896. In 1925, the original area railings and porches were removed and replaced by a new gallery designed by Joseph Goldie.

The buildings are constructed of brown brick in Flemish bond with red brick dressings. The roof is concealed by a parapet. The ground floor and basement projection are stuccoed, and iron railings, some re-sited, remain in place.

Each of the two town houses is four storeys with basement and three bays. Originally, they had entrance porches to the left-hand bays and two principal rooms on each floor. The original plan was later modified by rear extensions, replacement of the porches with a ground and basement projecting extension, and some later internal partitions.

The north-west or entrance front features a parapet with stone coping and terracotta decoration. Windows above ground floor are mainly 12-pane sash windows in reveals, except the top floor of the eastern part which has nine-pane sashes. When the 1925 extension was added, the original ground floor windows were enlarged. The new extension has round-headed windows to the ground floor linked by impost bands and an off-centre projecting doorcase with a round-headed arch, approached by a flight of steps with solid balustrades and crowned by a swan's neck arch with central cross on plinth. A narrower entrance with round-headed fanlight is located to the east. Plain 20th century area railings remain, though some re-sited panels with heart and honeysuckle motifs are preserved on the right-hand side of the area.

The south-east or rear elevation is similar but has only two windows across each house and later multi-storey projections. A number of multi-pane sash windows survive, though others have been replaced. The western property retains a cast iron conservatory on the first floor with anthemion motifs to the balcony and French windows. A flat-roofed stuccoed extension to the ground floor and basement of the western part with segmental-headed sash windows appears on the 1896 Ordnance Survey map but was probably altered in the 20th century as it differs from an 1895 bird's eye view of the convent and school.

The other exterior walls are obscured by the convent chapel to the east and the convent school building to the west.

Internally, each house retains an original staircase from ground to second floor with cast iron railings imitating bamboo but with a wooden handrail featuring decorative ends. The eastern house additionally retains an original staircase from second floor to attic, while the western house has an early 20th century wooden staircase in this position. The western part ground floor retains a plaster cornice, ceiling rose and black marble fire surround in the former parlour. The ground floor room of the eastern part also retains a plastered cornice and ceiling rose. Several other rooms retain cornices and window shutters, four-panelled doors and skirting boards.

THE FORMER CONVENT SCHOOL BUILDING

This building was designed by architect George Goldie in Gothic style in 1875 and built in successive phases during 1875-6, 1882 and 1888-9. The late 19th century section of the former convent to the west of the main L-shaped block is not included in this listing.

The building is constructed of yellow brick in English bond with stone cornice, band and window cills, polychrome red brick window heads and black brick bands. Cast iron balconettes, wooden casement windows and slate roofs with brick chimneystacks complete the external finish.

The plan forms a roughly L-shape comprising three storeys, basement and attics. The eastern part extends ten bays to the east and projects by five bays to the south, with a two-storey wing to the west. The eastern part has a northern corridor to the lower floors and central corridor above. Historical photographs of the convent school indicate dormitories occupied the south wing. A plan dated 1875 shows the west wing originally contained a recreation hall on the ground floor and a drawing room with eight piano practice rooms on the first floor.

The south-east side features five original gabled dormers with finials and five early 20th century larger flat-roofed dormers. An elaborate stone cornice with dentils and pilasters runs between the bays on the first and second floors. Second floor windows are tall casement windows with cast iron balconettes featuring quatrefoil motifs and French windows. First floor windows are pointed-arched multi-pane casements. Ground floor windows are larger pointed-arched casements with central septfoil motifs flanked by trefoils above trefoil-headed casements. The semi-basement has segmental arches to the windows and iron grilles, an off-centre pedimented doorcase and a smaller segmental-headed entrance.

The north-west side is identical to the south-east side but is interrupted by a 1960s full-height projecting brick and glazed lift occupying one bay.

The projecting attached five-bay south L-wing is similar to the longer wing and has two dormers along the sides. It differs only in having no balconettes to the second floor windows and a rendered projecting plinth. Its south-east end comprises two bays with a pediment containing two cinquefoil oculi divided by a central pilaster merging into a buttress, with corner clasping buttresses.

Adjoining the west side of the L-wing is Goldie's two-storey west wing with four narrow first floor windows to the original music practice rooms, three further casement windows and arched windows on the ground floor. It is partially obscured to the south by the 1960s single-storey assembly hall by C. Lovett Gill and Partners.

The basement contains a vaulted corridor. The main staircase has turned balusters and carved newel posts. Several large rooms on the ground and first floors have stone corbels and wooden beams to their ceilings, some painted. The Library retains an original white marble fireplace. A first floor corridor has panelled doors with transom lights. A second floor corridor features a series of wooden panelled doors with transom lights later blocked, probably originally nuns' cells. The attics contain some exposed roof timbers, some boarded.