20 Knock Road, Douglas Bridge, Strabane, BT82 8QR

A detached three-bay single-storey direct-entry vernacular dwelling built around 1830, located to the south of Knock Road.

The building is a simple rectangular-plan structure with a windbreak porch to the north, a bed outshot to the south, and a lean-to shed also to the south. The walls are lime-rendered rubble construction. The roof is pitched corrugated asbestos laid over the remains of the original thatch, which can be seen internally. A lime-rendered rubble chimney is present.

Windows are timber-framed 1/1 sliding sash with sandstone sills supported by timber lintels. The principal elevation faces north. The left bay contains a single window; the central bay contains a single window at left, flanked at right by the windbreak porch with a stone flat roof and vertically-sheeted timber door; the right bay contains two windows. The east gable is blank and is abutted by the remains of a rubble byre. The south elevation contains two windows in the left bay and one in the right bay, with the central bay abutted at right by the bed outshot; an exposed section at left contains a single window. The west gable is abutted by the lean-to shed, which contains a vertically-sheeted door to the east and a single window to the west.

The building is set parallel to the road to the north, with the remains of a rubble outbuilding to the north-east. It is bounded to the road by hedging and to other sides by rubble walling.

The house appears on the first edition Ordnance Survey map of 1832–3 together with a small outbuilding to the east, both of which have survived. A lime kiln is also shown on this map. In Griffith's Valuation of 1859, a "house, offices and land" is listed as occupied by Josias Irvine and leased from the Marquis of Abercorn, valued at £1. The house remained in the Irvine family; in 1909 James Irvine became the owner in fee under land purchase legislation of the early twentieth century. After 1934 Josiah Irvine is recorded as the owner, with the valuation raised to £2 and 10 shillings for outbuildings. At that stage the house comprised a kitchen, two rooms, and three small rooms. The house was of rubble masonry and thatched at that date.

The loss of original fabric due to deterioration has detracted from the character of the building. It does not meet the criteria for listing.