59 Greencastle Street, Kilkeel, Newry, Co Down, BT34 4BH

59 Greencastle Street is one of a pair of single-storey, two-bay direct-entry thatched vernacular dwellings, constructed in the early 19th century, situated on the south side of Greencastle Street in Kilkeel. These represent a rare survival of what was once a common village house type, and are among only a tiny number of surviving original thatched houses in the Mourne area.

The building is a pair, with No. 59 positioned to the left as viewed from the road and No. 61 to the right. Both have extensions at the rear and side. The main structures are topped with a traditional pitched thatch roof featuring a wrap-over ridge, rendered verges, and wired eaves secured with two rods at the ridge and one at the eaves. Two smooth rendered chimneys are present: one on the right gable of No. 61 and the other on the party wall between the two properties.

No. 59 has wet cement-dashed walls. Its street-facing elevation displays a vertically-sheeted half-door positioned in the middle, with a 2/2 vertically-divided sliding sash window to the left and a three-pane fixed vertical window to the right, both set in narrow concrete cills. The left gable is blank, while the right gable forms the party wall with No. 61.

The rear elevation of No. 59 is abutted by a short link block providing access to rear annexes. The link block belonging to No. 59 is positioned at the extreme right, with its flat roof cutting into the rear pitch of the main thatch. Its yard-facing elevation features a tongue-and-groove sheeted door flanked by a 2×3 fixed timber light on each side. The opposite face, flush with the left gable of the main block, is blank. The exposed section of the main block to the left of the link block contains a 2/2 sash window with cement-rendered dressing and cill.

The one-storey annex has a pitched natural slate roof with walls matching the main block. Its rear (south) elevation contains a 2/2 sliding sash at the centre, with a pair of 2/2 sliding sashes positioned to either side. All other walls of the annex are blank. Part of the roof timberwork is original.

Historically, the valuation town plan of circa 1835–38 shows a structure of this size and shape at the site, but it was then composed of three small separate dwellings rather than two. These three properties were exempt from rating due to their modest size, so their dimensions and occupants were not recorded. By 1862, the three dwellings had been combined to form one large property, with the occupant listed as William Hanna and the Earl of Kilmorey as lessor. The measurements recorded for the house section were 14 yards × 5 yards 2 feet × one storey, with offices (stores or outbuildings) measuring 5 yards 2 feet × 55 yards 2 feet × one, 11 yards × 55 yards 2 feet × one, and 3 yards × 45 yards 2 feet × one. The latter office appears to have been a small addition made after 1838 to the northeast gable. Annotations to the valuation map show that the previous three-property division was reinstated shortly after 1862, a situation that lasted at least until 1929. Sometime after 1929, the block was reconfigured as two dwellings, forming the present Nos. 59 and 61.