Wave Trauma Centre, Rathvarna House, 5 Chichester Park South, Belfast, Co. Antrim, BT15 5DW

Rathvarna House is a detached, asymmetrical, multi-bay, two-storey house with attic, built in 1877 in the Gothic Revival style from local sandstone. It was designed by the prominent Belfast architect Robert Young as his own private residence, and the listing covers the house and its gate screen.

Robert Young (1822–1917) was a highly significant figure in Belfast's architectural history. He established an independent practice in the city in 1852 before entering into partnership with his former pupil John Mackenzie around 1867, forming Young & Mackenzie — described by the Dictionary of Irish Architects as the most successful architectural practice in Belfast, leading architects for the Presbyterian church in the north-east and recipients of some of the most important commercial commissions in the city. Young had previously lived at No. 268 Antrim Road and at Fortwilliam Villas (which he also designed) before moving to Rathvarna. The random coursed rock-faced sandstone façade is characteristic of Young & Mackenzie's work and closely resembles the firm's contemporaneous buildings at Belfast Royal Academy, the Crescent Arts Centre, and the Culloden Hotel. Young occupied Rathvarna until his death on 21 January 1917, having lived there for roughly forty years. The 1901 Census described the house as a first-class dwelling with sixteen rooms and a single shed as an outbuilding. The land was originally leased by a Mr Thomas B. Johnston, and the house was first recorded in the Belfast Street Directories in 1877, with a total rateable value of £60 set in 1879.

On Young's death, the house passed to his son Robert Magill Young (1851–1925), who had entered partnership with his father in 1880. Robert Magill Young was also a local magistrate and lived at Rathvarna until his own death in 1925, when the property passed to his son James Reid Young. The Dictionary of Irish Architects records that J. R. Young was a partner in Young & Mackenzie for over forty years and lived at the family home at Chichester Park South until his death in 1967. Under the First General Revaluation of Property in Northern Ireland (covering 1936–57), the rateable value was increased to £94, a figure that remained unchanged through the Second General Revaluation (1956–72). The house was listed in 1985 and underwent an extensive renovation in 1987–88, fittingly carried out by Young & Mackenzie, which included repointing of the stonework. The building remained in residential use until around 2000, when it was converted into victim support and office accommodation for the WAVE Trauma Centre. Single-storey and two-storey rendered extensions were added to the northwest at that time. Rathvarna House lies within the Somerton Road/Chichester Park Conservation Area, designated in 2000 on the basis that the area exhibits a very high standard of townscape character, with many period Victorian and Edwardian properties contributing to the special quality of its suburban setting.

The building is irregular on plan, facing east, and set back on the west side of Chichester Park South within its own mature grounds. The roofs are pitched natural slate with roll-moulded terracotta ridge tiles, mortar parged verges, and several rock-faced sandstone ashlar chimney stacks. Rainwater goods are replacement uPVC, supported on exposed timber rafter feet. The walling throughout is random coursed rock-faced sandstone ashlar with cement pointing, tooled corners, and a rock-faced plinth course with splayed ashlar trim. Window openings are largely square-headed with chamfered or bowtel-moulded red sandstone dressings, flush splayed sills, and original single-pane timber sash windows with slender ogee horns, except where noted otherwise.

The principal elevation faces east and is three windows wide. It has a full-height gabled projection to the left, a central entrance bay, and a large chimney stack abutting to the right. The gabled projection features a corbelled-out canted oriel window at first-floor level, formed in ashlar sandstone and embellished with decorative foliate and grotesque carvings. The ground-floor window openings on this projection are shouldered, with shouldered upper sashes to match. A single wall-head dormer window sits over the entrance bay, with sandstone coping and shoulder blocks. The central door opening is square-headed, formed in a tooled sandstone surround with carved roundels, bowtel mouldings, and foliate embellishments to the lintel, surmounted by a four-centred arch overlight. The original timber door is wood-grained with linenfold panels and iron door furniture, and opens onto a concrete platform approached by six concrete steps enclosed by a rock-faced sandstone wall with replacement steel handrails.

The south side elevation is two windows wide and is abutted by a full-height gabled projection with paired windows at each level. To the right of this projection is a large chimney stack, now truncated, with a lean-to greenhouse at ground level. To the left of the projection is a steel fire escape. Window openings on this elevation are generally pointed-headed with single-pane timber sash windows. The paired ground-floor windows within the projection have a single polished granite column with a stiff-leaf capital, red sandstone tympanums with quatrefoil lights, and six-pane timber casement windows. A catslide dormer roof to the left contains a replacement hardwood glazed door opening onto the fire escape. This elevation extends westward as a lower two-storey extension, with rock-faced sandstone walling at ground-floor level and painted smooth rendered walling to the upper floor, with concrete sills and timber sash windows.

The rear elevation is abutted by the south-west extension described above and a further single-storey rendered extension to the north-west. Between the south-west extension and the north wing is a tall brown brick lift shaft. The north wing has a half-hipped roof and a stone-framed stairhall window with paired trefoil-headed lancets and a quatrefoil above; this window retains its leaded latticed glazing with storm glazing added.

The north side elevation is four windows wide, with a full-height canted bay window to the left and a single wall-head dormer with a shouldered window opening. Below the dormer is a pair of pointed-headed window openings, while the remaining openings on this elevation are square-headed.

Although the building has been substantially modified — most notably by the single-storey and two-storey rendered extensions added to the rear around 2000 — many well-crafted internal features survive intact. The external composition retains much of its architectural character, with fine stone detailing and good proportions throughout.

The house sits within its own mature landscaped gardens on a quiet residential road. The boundary to the road is formed by a low rubblestone wall, with entrance through modern steel gates flanked by original circular sandstone piers with red sandstone tapered capstones.