Thompson House, 426 Antrim Road, Belfast, BT15 5GA

Thompson House is a mid-terrace, two-bay, three-storey red brick and stucco Victorian house with attic, built in 1872 to the designs of Redfern Kelly (1845–1928), a Belfast-based engineer best known for his work on behalf of the Belfast Harbour Commissioners. It forms one of seven similar houses originally known as Fortwilliam Terrace, occupying a slightly elevated position set back on the west side of Antrim Road and screened by a series of mature trees behind a low rendered wall. The building is rectangular on plan, facing east, and retains its original gable-ended lower three-storey red brick return. It is now interconnected at all levels with the adjoining No. 428 Antrim Road and is in use as hostel accommodation.

The terrace as a whole has a distinctive character defined by its vertical emphasis, graduated fenestration, and restrained neoclassical stucco mouldings. The roof is finished in natural slate with roll-moulded black clay ridge tiles, and features a lead-lined dormer window set behind a stucco parapet wall with a deep moulded cornice and plain frieze. There is an original shouldered rendered chimney stack with lipped clay pots to the north party wall, a concealed parapet gutter to the main roof, and uPVC downpipes to the rear and to a single-storey canted bay at the front.

The red brick walls are laid in Flemish bond with cement pointing. Continuous moulded string courses run at first and second floor sill levels. Window openings are square-headed with decorative stucco surrounds, moulded sills, and original single-pane timber sash windows with ogee horns throughout. The two-bay, three-storey east front elevation is abutted at ground floor level by a painted rendered three-sided canted bay window, which has a continuous masonry sill, a plat band, and a shallow cornice to the parapet. At second floor level, the windows have decorative painted lugged architrave surrounds with bracketed sills. The first floor windows are framed by scrolled foliate console brackets supporting a hood cornice, with moulded sills supported on stepped brackets.

The door opening is round-headed, built in gauged brick with a projecting bull-nosed surround, and positioned in the left bay. The original painted timber panelled door has four raised-and-fielded panels and brass furniture, flanked by fluted Ionic columns supporting a dentilated lintel cornice, with a plain glazed fanlight above. The door opens onto a terracotta tiled platform leading to three steps down to a bitmac and block-paved front area, enclosed by replacement steel railings and a pedestrian gate. Low plinth stone walls flank the entrance steps and feature carved anthemion panels, adding further architectural interest.

To the rear, the red brick elevation is abutted by the original gable-ended three-storey red brick return, which is rendered at ground floor level. The rear window openings are square-headed in gauged brick with painted masonry sills and original timber sash windows — single-pane at second floor level, and two-over-two panes with horizontal glazing to the ground and first floors. A shared bitmac driveway runs to the front, and there is an enclosed rear yard.

The building sits in the townland of Skegoneill, an area that was largely rural in character as late as the 1850s, as recorded on the second edition Ordnance Survey map. With the rapid growth of Belfast's shipbuilding, rope-making, and textile industries through the mid-19th century, the area swiftly developed into one of the most affluent parts of the city, attracting merchants and professionals moving out of the overcrowded inner city. Fortwilliam Terrace was built on the grounds of Hopefield House, a two-storey, six-bay mansion formerly occupied by the Sinclair family, the majority of whose grounds were built over during the 1870s. The terrace was leased by Samuel Lawther, manager of Samuel Lawther and Co., local coal importers, ship and insurance brokers based on Corporation Square.

Redfern Kelly, who designed the terrace, was responsible for significant engineering works including the deepening of the Victoria Channel, the reconstruction of the Alexandra Graving Dock following its collapse in 1905, and the construction of the Thompson Graving Dock. Beyond his industrial work, Kelly also designed a Masonic Hall in Larne and the Murlough Cottages in Dundrum. A similar terrace formerly known as Castleton Terrace, also thought to have been designed by Kelly and built in 1878, sits almost directly opposite on the east side of Antrim Road.

The Annual Revisions record that No. 426 was initially valued at £40 and that its first occupant was a Mr A. Millar, a local manufacturer and confectioner. By 1901, the house was occupied by Joseph Macauley, a solicitor, and the census building return described it as a first-class dwelling of 14 rooms. In the 1930s it was home to Samuel Carlisle, assistant manager to the Belfast Tramways. The First General Revaluation of Property in Northern Ireland (1936–57) raised the assessed value to £46, a figure maintained through the Second Revaluation (1956–72). The terrace was listed in 1987. In 1993, the building underwent renovation that included the restoration of its original sliding sash window frames and the installation of cast aluminium rainwater goods. That same year, the hostel use that had been established in the adjoining No. 428 — administered by the Presbyterian Church in Ireland — was extended into No. 426, and the pair continued to be used as a hostel at the time of the second survey.

Despite modifications to the internal layout, the building is largely intact. The survival of the original return adds to its historic value, and it has group value with the other listed buildings in Fortwilliam Terrace.