86 Summerhill, adjacent to 117 Dunadry Road, Dunadry, Antrim, Co Antrim, BT41 4QJ

A three-storey, fourteen-bay tenement block built in the early to mid 19th century as workers' housing by the York Street Flax Spinning Company of Belfast. Although the precise date of construction is not known, the building appears on the Ordnance Survey map of 1857, placing it within the period 1840–1859. It is constructed in basalt rubble with granite and red brick dressings and is now in derelict condition following prolonged abandonment and structural collapse.

The building has an unusual form and plan. Ground floor single-storey units face west and are accessed directly from that elevation, while the two-storey upper units face east and are approached by a railed pedestrian ramp and external balcony running the full length of the building. This arrangement allowed separate access for different classes of tenant.

The west elevation features a hipped roof of Bangor blue slates in regular courses with five red brick chimneys along the main ridge. The ground floor walls are of roughly coursed basalt rubble with red brick block dressings to the openings. The upper floor stonework is panelled, with window openings set in large rectangular red brick panels positioned between deep horizontal bands of basalt and divided by vertical strips of basalt quoins. Tardree granite quoins mark the extremities of the block, and a Tardree granite eaves cornice gutter runs along the top. A blocked elliptical stone archway in the centre of the ground floor contains a rectangular doorway and window set in brickwork. Doorways throughout are rectangular red brick openings containing 4-panel timber doors; windows are rectangular timber sliding sash, 6 over 6 with horns, now largely derelict with some entirely missing. The first two bays from the left on the upper floors have suffered wall collapse.

The north elevation is three-storey and two-bay, with walling similar to the ground floor of the west front, featuring two windows to each upper floor and one doorway to the ground floor. The east elevation is similar to the west except for the absence of a central archway and the presence of the balcony at first floor level. The balcony comprises a flat concrete slab with plain iron balustrading, supported on projecting iron brackets and reached by a balustraded ramp supported on circular cast iron posts. Extensive collapse has occurred on this elevation, with walling lost from five second floor bays and four first floor bays, bringing down part of the balcony; the entrance to the approach ramp is now railed off. The south elevation is similar to the north except that openings to the top and bottom floors are now blocked with red brick.

The building stands in a very rural setting at the end of a long lane from the main road, surrounded by grassy grazing land with a river nearby and mature trees in the vicinity. Running parallel with and close to its east side is a terrace of single-storey outbuildings in red brick with slated roofs, presumably originally outside toilets, now derelict. Further to the west in an adjoining field is a group of one and two-storey brick buildings with slated roofs and Gothic arched openings, all now derelict.

The building was known locally as the 'Bird Cage'. It was described as almost completely derelict by 1969, although one unit remained occupied in 1972. The date of the wall collapse is not known. The listing extends to the housing block including the ramp, outhouses, and associated dwellings.