Portaferry House, Ballymurphy, Portaferry, Newtownards, Co Down, BT22 1PP

Portaferry House is a large, three-storey country mansion in restrained classical style, built around 1750 and extended around 1790, but substantially remodelled in 1818-20. It stands within an extensive demesne, approached by a half-mile drive from Deerpark Road through rough pasture and mature copses of predominantly indigenous trees.

The south-facing front elevation is symmetrical in three bays. The central bay rises three storeys and is flanked by broad canted bays with hipped roofs that are equal in height to the central section but contain only two storeys. A flat-roofed projecting porch occupies the centre of the ground floor, with double three-panelled timber doors flanked on each side by two attached columns and corner pilasters. All have cushion bases and Ionic capitals supporting an entablature. The porch side walls each contain a sliding sash window without astragals. On either side of the porch are two tall sliding sash windows with Georgian panes. The first floor of the central section contains five windows; the central window is tripartite and surmounted by an elliptical relieving arch with keystone and infilled tympanum, flanked by two sash windows matching those at ground floor. The second floor of the central section mirrors the first floor arrangement but without the relieving arch above the tripartite window. Both first and second floor windows of the central section rest on a cill course. The three-sided outer bays contain similar sash windows. The entire elevation is line rendered with moulded architraves to all windows; all except the ground floor bay windows rest on cill courses. A projecting frieze cornice tops the walls.

The west elevation of the main block is two storeys with three unevenly spaced windows at both ground and first floor levels. The frieze cornice, window bands and surrounds match the front elevation. Plain stone quoins mark the corners against rendered walls. A six-pot chimney stack rises on the parapet above the cornice. A small window has recently been inserted below first-floor level between the first and second windows.

The east elevation is three storeys, as ground level falls away to reveal a semi-basement. The basement level contains four equally spaced openings with double timber French doors leading onto a stone-flagged terrace; the third opening is covered by a Victorian-style wooden conservatory. The first and second floors each have four equally spaced windows with surrounds. A string course runs between ground and first floor openings, while second floor windows rest on cill courses. Frieze detailing matches the front elevation.

The rear elevation has a functional appearance and comprises various extensions of differing heights, ages and roof forms: flat-roofed, lean-to and pitched-roof sections of two and three storeys. To the left is a relatively large two-storey hipped-roof return, which links to a much larger three-storey hipped-roof return extending from the main block. Immediately west of these is a small two-storey flat-roofed section, which links to a very large three-storey block arranged in several bays with mixed flat and hipped roofing. Windows throughout vary in size; the large three-storey western block contains mainly sash windows, with particularly large stairwell windows to its left side. The small flat-roofed section has modern window openings with modern frames. All windows have either Georgian or Georgian-like panes. Each return, extension and bay is mainly covered in lined render. Below the window cill to the grand staircase is a small, weathered plaque bearing the Savage/Nugent coat of arms.

The main roof is hipped and covered in Bangor blue slates. Seven rendered chimney stacks, relatively plain in appearance with simple cornicing and string courses, rise from various points of the roof.