Graymount House, (Hazelwood Integrated College), 70 Whitewell Road, Belfast, BT36 7ES

Graymount House is a detached, five-bay, two-storey symmetrical Classical mansion built around 1835 to the designs of Thomas Jackson (1807–1890) for William Gray, a linen merchant and founding director of the Ulster Railway Company. Jackson had only just established his independent architectural practice that year, making this one of his earliest commissions. The building stands in an elevated position within the grounds of Hazelwood Integrated College on the Whitewell Road, in the townland of Greencastle, overlooking Belfast Lough.

The Townland Valuations of 1835 record the house as a first-class structure — defined as a new or nearly new slated building — measuring 57 feet in length, 22 feet in breadth, and 18 feet in height. At that time the property also included a rear return, a coach house, and a gate lodge, and was valued in total at £40. Gray leased the site from the Marquis of Donegall, and his bleaching concern — operated under the name William Gray & Sons — was situated to the west of the mansion and was substantially larger than the house itself. By the time of Griffith's Valuation in 1859, the rateable value of the mansion had risen to £116, with the gate lodge separately valued at £2 and 10 shillings.

The exterior is finished in render throughout. The principal east elevation presents a five-bay, two-storey symmetrical façade with a single-storey Ionic entrance portico set on a plinth, approached by stone steps. The ground floor is rusticated render with a projecting plinth and a smooth banded string course; the first floor is smooth render. Coupled smooth rendered pilasters flank the elevation and the entrance portico. All window openings are square-headed with moulded surrounds and overhanging sills, and the ground-floor openings carry projecting moulded hoods. Windows throughout are six-over-six pane single-glazed timber sliding sashes. The entrance doorway is square-headed with a fanlight and side-lights, a raised apron panel, and flanking pilasters; the double-leaf timber panelled entrance doors feature decorative scrolled iron insets, and the surround to the doors and side-lights is moulded.

The south elevation is four bays wide over two storeys, with a lower two-bay, two-storey extension separated from the main building by a narrow glazed flat-roofed link block. The ground floor is rusticated render with a raised plinth and string course; the first floor is smooth render. Smooth rendered clasping pilasters appear at both ends, and the windows match those on the principal elevation — square-headed with moulded surrounds, stone sills, and six-over-six timber sliding sashes. The north elevation is largely a mirror image of the south, again with a four-bay, two-storey main range separated by a narrow glazed flat-roofed link from a lower two-bay, two-storey extension. The west elevation belongs to a two-storey, four-bay extension, which has rusticated render to the ground floor and smooth render to the first floor, with a projecting sill course and eaves course and square-headed openings with smooth rendered surrounds. The return face of the clasping pilasters and the moulded cornice at the parapet of the original house's west elevation are visible here, though the remainder of that elevation is obscured by the later addition. The entrance portico has a flat roof with a raised cornice moulding.

The roof of the main house is hipped natural slate with lead hips and ridge, and a raised moulded parapet to the north, south, and east. A hipped-roof lantern sits above the west section of the original house. The chimneys project from the north and south hips and feature rectangular insets, projecting stone coping, and five octagonal stone pots each. Rainwater goods are a mixture of cast-iron and uPVC guttering and downpipes. The west extension has a hipped slate roof.

Internally, the building retains much of its historic detail in excellent condition. Paul Larmour, writing in 1987, described the interior as having bold panelled ceilings, good marble fireplaces, an Ionic hall screen leading to an impressive double-return stair, and a large spacious lantern soaring above.

The building has a notable ownership history. William Gray lived at Graymount until his death around 1860, when the property passed to his relative Captain George Gray, a local magistrate and Justice of the Peace. After George Gray's death around 1880, the mansion was administered by the trustees of his estate — James and Acheson Gray — and appears to have remained vacant until 1907. Between 1907 and 1910 the house was occupied by Sir Thomas Dixon (1868–1950), son of Sir Daniel Dixon, 1st Baronet and Lord Mayor of Belfast. Thomas Dixon went on to serve as High Sheriff of Antrim in 1912 and as Lord Lieutenant of Belfast and a member of the Northern Ireland Senate from 1924 until his death in 1950. After Dixon vacated the property, it was acquired in 1911 by Jonathan Vint, a local wine merchant, who renamed it Mount Moan. The 1911 census return describes it at that time as a first-class dwelling of 15 rooms, with a stable, coach house, fowl house, and shed to the south-west. The property continued to be owned by the Gray family until at least the 1970s, while the Vint family occupied it until the 1940s.

Under the First General Revaluation of Property in Northern Ireland (covering 1935 to 1956), the building was converted into a school administered by Belfast Corporation and valued at £110. It became known as Graymount Intermediate and Open Air Special School, and from the 1950s onwards was expanded with the addition of modern school blocks, including a gymnasium designed by R. S. Wilshere, causing the rateable value of the entire site to rise to £5,200 by the end of the Second Revaluation period (1956–72). A modern annex to the rear was demolished in 1992 and replaced by the current two-storey, five-bay extension to the east and rear of the main house, designed in a sympathetic style and completed around 2005. Dean has also suggested that Graymount may have been a redevelopment of an earlier building known as Greencastle House.

The building was listed in 1987. It is sited within the grounds of Hazelwood Integrated College, which contains several other 20th-century single- and two-storey school buildings. The boundary to the south is formed by hedging; parking and the road lie to the north and east; and a tree-lined boundary runs along the west.