81 Castlewellan Road, Banbridge, Co Down, BT32 4JD

Ballydown House (formerly known as Roselawn) is a two-storey, five-bay house predating 1833, substantially altered around 1870. Its overall character is of the later 19th century, with proportions and detailing typical of that period, although the rear has been modified with extensions and replacement materials that compromise its appearance. The setting, including the outbuildings and the remains of the 19th-century walled garden, largely survives. The house was formerly the mill master's residence for the bleach mills that once stood to the south-east on the banks of the River Bann, now demolished. It is a representative example of this building type, though not among the finest surviving examples.

The house has a rectangular plan form with a porch, double-height canted bay windows, a rear return, and a side extension. It sits on the south side of Castlewellan Road to the east of Banbridge town centre, west of the A1. The roof is pitched natural slate with clay ridge tiles, and the rainwater goods are extruded metal with an ogee moulded profile. The chimneystacks are smooth rendered with heavy moulded cornicing and tall moulded octagonal clay pots. The external walls are smooth rendered with raised long-and-short quoins. Windows on the principal elevations are 2/2 timber sliding sashes with horizontal glazing bars, horns, and masonry cills. The front door is a modern timber-framed unit with three glazed upper panels.

The principal, south-facing elevation is symmetrically arranged. At its centre is a single-storey flat-roofed porch with a decorative metal parapet; the door is set to the left cheek of the porch, with a tripartite window to the front and a further window to the right cheek. On either side of the porch is a single window at ground-floor level, with three first-floor windows directly above. The outermost bays on both left and right are two-storey canted bays with moulded apron panels and hipped roofs terminated with clay finials. The left gable is blank.

The rear elevation is asymmetrically arranged around a central two-storey return, and uPVC replacement windows have been fitted throughout this elevation. To the left of the return there is one ground-floor window and two first-floor windows; to the right of the return there are three first-floor windows and one ground-floor window adjacent to a lean-to extension, though the view here is partially obscured. The gable-ended return has two ground-floor windows in its gable end; the left cheek has a door to the left and a single ground-floor window to the right, along with two first-floor windows. The right cheek has two first-floor windows, with the ground floor abutted by a lean-to roof extension, again partially obscuring the view.

The right gable is abutted by a subordinate two-storey gabled extension. The south elevation of this extension features a wall-headed dormer above a single-storey modern timber-framed conservatory that abuts it. The gable of the extension has a single window next to a single-storey pitched-roof store set perpendicular to the extension, which in turn adjoins an outbuilding. The north elevation of the extension has a door and a single window.

The house is prominently visible from the A1, partially screened by trees to the north. Access is through a modern gated entrance with a straight driveway approach; there is a garden to the left and a wooded area to the right. To the west of the house are the remains of part of the former walled garden, which now occupies the space used as a horse paddock to the south. To the east is a single-storey outbuilding with a chimney that adjoins the dwelling; it is roughcast rendered with replacement windows and roofing. Beyond the concrete yard is a further two-storey rubble masonry stable block with brick dressings to the openings, significantly altered with new openings, replacement windows, and new roofing.

The house was originally constructed prior to 1833 and is first depicted on the first edition of the Ordnance Survey map of that year as a rectangular dwelling occupying the footprint of the current building, surrounded by a number of outbuildings. A bleach mill to the south was constructed along a mill race cut from the River Bann and is now demolished, along with the majority of the original outbuildings. The Ordnance Survey Memoirs record that the bleach mill was the property of a Mr Mulligan, and the Townland Valuation records that John and George Mulligan owned a beetling mill valued at £10 7s and a number of other mills valued at £6 16s in the parish. George Mulligan is understood to have occupied Roselawn whilst his brother John resided at Parkmount House; George Mulligan died in 1845 during his 47th year at Roselawn, which suggests the site may date from at least the late 18th century.

By 1859 there had been little discernible change to the layout of the house. Griffith's Valuation of around 1862 records that by the early 1860s Roselawn, valued at £13, had passed to a Ms Jane Dobbin, who leased the site from Robert Fennell and Company, with Fennell utilising the bleach mills to the south. In 1866 a Mr William Malcomson took possession of the mill and by 1869 had also acquired Roselawn House. The house appears to have been modified around that time, as its rateable valuation rose from £13 to £22, with a further increase to £30 recorded by 1876. William Malcomson and Co. originally came from County Waterford and constructed a new mill at the Ballydown site in the 1860s. Between 1869 and 1884 Roselawn was occupied by a small number of tenants, including James McWilliams, manager of the Ballydown mill.

After McWilliams's death in 1884, Messrs James Anderson and Co. took possession of both the textile factory and Roselawn House. Bassett's Directory of 1886 records that Anderson and Co. confined their efforts exclusively to linen yarns, bleaching all grades from brown to full white, employed 30 people, and used steam as an auxiliary to the water power provided by the Bann. James Anderson, the company owner, occupied Roselawn as his personal dwelling. The 1901 Census records Anderson (aged 50, Presbyterian) living at Roselawn with his wife Mary (aged 40) and their three children, employing a number of domestic servants. The census building return described Roselawn as a first-class dwelling consisting of 14 rooms, with farm offices including a stable, two cow houses, a piggery, fowl house, and barn in the outbuildings to the south and south-east. James Anderson died in 1902, leaving Roselawn to his son Thomas N. Anderson, who continued to live there until at least the 1930s. The 1911 Census records Thomas Anderson as a linen yarn bleacher and dryer who had taken over his father's business. No further alteration to the site was recorded by the end of the Annual Revisions in 1929.

By the time of the third edition Ordnance Survey maps of 1902–03, the two-storey rear return and the southernmost surviving outbuilding had been added and were depicted as new features. The bleachworks to the south of the house were erected by Malcomson in 1866, replacing the former mills established by the Mulligans, and were eventually demolished sometime after they were last shown on the 1974 Ordnance Survey map. Prior to demolition, the buildings and equipment were recorded as having remained substantially unaltered since 1866, with motive power provided by a combination of electricity and a timber and iron undershot wheel of 14 feet in diameter. No trace of the Ballydown Bleachworks survives today.

The house was renamed Ballydown House sometime between the fourth edition Ordnance Survey map of 1903–18 and the 1974 edition, which first shows it under that name. A corrugated-iron barn was erected to the east of the house by 1974. In more recent years the only recorded change to the site has been the addition of a modern conservatory. In later years the house was home to James A. Beck, who was employed as a chemical supplier to the local linen industry.