25 Ballymullan Road, Crawfordsburn, Bangor, Co Down, BT19 1JG

Coolnashee is a single-storey house with two attic floors, arranged in three bays, detached and built in the Domestic-Revival style. Dated 1926, it stands on a large mature site north of Ballymullan Road in Crawfordsburn.

The building is rectangular in plan with dormers, a canted bay to the west, a box-bay to the south, and a single-storey extension to the east with a garage to the south. The roof is steeply pitched with rosemary tiles, half-hipped with a gablet and projecting purlins, and angled ridge tiles. A roughcast-rendered chimneystack rises to the rear slope with six clay pots, and a smaller chimneystack to the ridgeline has three clay pots. A roof tower in the form of a dovecote stands to the east. Cast-iron half-round rainwater goods run along timber-panelled overhanging eaves; a cast-iron hopper is dated "1926". The walling is painted roughcast render on a recessed red-brick plinth, with stretcher-bonded red-brick to the veranda. Timber panelling in Tudor style adorns the entrance bay on the north elevation.

Windows throughout are varied multi-pane steel casements with leaded glazing and terracotta-tiled sills. Bay windows have rosemary-tiled roofs, and dormers feature steeply overhanging roofs. The north (entrance) elevation displays three multi-pane hipped dormer windows with glazed cheeks—the centre one is tri-partite and surmounted by two small roof-lights; the flanking dormers are bi-partite. The central entrance bay is timber-panelled, slightly recessed, and comprises a single lattice window with timber sill, flanked on either side by a slightly projecting porch accessed by two red-brick steps. A Gothic-style three-panelled timber door in Tudor-style timber-panelled surround features decorative cast-iron panels and door furniture. The entrance bay is flanked by multi-pane tri-partite windows.

The east elevation displays a half-hipped gablet roof detail with overhanging eaves on projecting purlins. An elongated multi-paned tri-partite window lights the upper attic floor, below which are three multi-pane windows to the lower attic floor—the left window is larger. A timber-sheeted dovecote tower rises to the left above the roof slope, terminating in a pyramidal tiled roof with finial. At ground floor, a half-panelled timber door sits at centre; to its left is a multi-pane window. A small single-storey hipped-roofed return abuts to the right, comprising a single multi-pane window to the north face, with blank south and east faces; a corrugated-iron lean-to abuts the east face, with its south face open. A larger single-storey hipped-roofed return abuts to the left, comprising a single window flanked by timber-sheeted doors to the north face, with a blank east face and a flat-roofed return abutting the south face. The abutments and east wall create a central yard partially covered with corrugated plastic roofing and accessed via a decorative iron latch gate.

The south (garden) elevation comprises a central gabled bay with a hipped roofed box-bay to the ground floor surmounted by a multi-pane bi-partite window. To the right is a multi-pane tri-partite window. A flat-roofed return to the far right features stepped parapet walls to the east and west faces, with a gutter to the south; a large window sits to the left and a diminutive window to the right on the west face, whilst the south face is blank and the east face has a door to the left and a large original garage door to the right. To the left is a recessed bay with an overhanging roof supported on three square timber columns to create a veranda, accessed by two brick steps—the porch is entirely in red-brick. To the right of the veranda is an original three-panelled timber door with diamond lattice glazing to the top section and a cast-iron door handle; to the left is a multi-pane bi-partite window. Above the rear door is a small multi-pane hipped dormer with glazed cheeks. The west elevation displays a half-hipped gablet roof detail with overhanging eaves on projecting purlins. Left of centre at ground floor is a single-storey hipped-roofed canted bay window, fully glazed over a plinth wall with two multi-pane bi-partite windows above. To the far right at ground floor is a timber-framed veranda infilled with multi-pane upper panel and solid lower panel.

The house has been well preserved and displays good Domestic-Revival style detailing, including the original fenestration. Although an interesting example of its type, it is of a late date and not of special architectural or historic interest.

The building is situated on a large mature site off a well-established residential street in Crawfordsburn village. A tarmacadamed driveway runs to the southeast, with mature garden to the north and a landscaped garden to the south featuring miniature hedgerows and shrubs, all enclosed by mature hedgerow and trees.

Coolnashee was first shown uncaptioned on the fifth edition Ordnance Survey map (1938–41). The area of land enclosed by Ballymullan and Ballyrobert Roads, to the west of Crawfordsburn, had been partially developed by the turn of the twentieth century, and the first few decades of the new century saw it divided into plots with substantial houses built on each. The earliest name associated with the house is John Ronald Howard Greeves, born 1900, a former pupil of Campbell College, and it appears likely that Greeves built the house for himself. Greeves graduated from Queen's University in 1921 in electrical engineering and served in the Second World War, reaching the rank of Lieutenant-Colonel by 1945. He was director of J and TM Greeves Ltd, Belfast, a very large flax-spinning concern with premises on the Falls Road that had been founded by his grandfather and great-uncle in 1862. Greeves was a keen amateur naturalist and a frequent contributor to the Irish Naturalists Journal on ornithological and botanical subjects. He became a Fellow of the Irish Genealogical Society and Chairman of the Ulster Genealogical and Historical Guild. His great-grandfather was the architect Thomas Jackson, and Greeves was born and spent many of his later years at Altona, a house built by Jackson in 1863–64. The house remains in use as a dwelling.