23 Altmore Street, Glenarm, Ballymena, Co Antrim, BT44 0AR

This is a low-proportioned, two-storey terraced house of possible pre-1832 construction, with a simple incised stone door surround added at perhaps around 1840. The property sits on the west side of Altmore Street in Glenarm, with its symmetrical front elevation facing east.

The ground floor of the front elevation is dominated by a panelled door with a rectangular fanlight containing decorative tracery. The doorway is framed by incised pilasters, a cornice hood and a blocking course. To the left of the doorway is a window with a plain sash frame, and to the right is a matching window. Three further windows sit at first floor level. The entire front façade is finished in painted render, with smooth cement bands forming the window surrounds, sill courses, a base course, and in-and-out quoins at the corners. Two rendered chimneystacks are shared with neighbouring properties. Rainwater goods are a mixture of cast iron and PVC.

To the rear, a large two-storey flat-roofed return projects from the left-hand side of the elevation. This return has three windows with modern frames on its west-facing first floor, and one window on each floor of its south face. The right half of the ground floor of the rear elevation is covered by a modern PVC lean-to conservatory. Above the conservatory, a small portion of the main rear wall remains visible, with one window fitted with a modern frame. The rear elevation is finished in unpainted roughcast. There is a small skylight to the rear of the main gabled, slated roof.

Altmore Street takes its name from the Altmore River, a narrow brook flowing from high ground to the south-east down to the Glenarm River to the west. Documentary references to building plots in the area go back to August 1673, when a lease mentions a "housestead, garden of tenement extending back to Altmore Brook." Further leases of December 1678 refer to "tenements" on the "south side of Altmore" and confirm the existence of a "street" at that date. Many of the earliest houses in the street may have been built on the western side, since before the walling in of the Glenarm Castle estate grounds in the 1750s the village fronted onto both sides of the Glenarm River. Some buildings on this side of the street may originally have faced the river: the present number 15, for instance, appears to have originally had an almost symmetrical rear elevation facing the river and a markedly asymmetrical street-facing front, while number 29 has a 1739 datestone on its river-facing side rather than its street-facing front.

The earliest surviving map of Glenarm, drawn up by John O'Hara in 1779, shows the street fully developed on both sides, with the western terrace stretching further south than it does today, beyond the line of the present Town Gate to the Glenarm Castle estate. The construction of the Town Gate at some point between 1832 and 1857 appears to have brought about radical changes to the layout of the street, with much of the eastern terrace pushed further east to allow for a broader and slightly grander approach to the estate. No mention of this widening has been found in any published account of the development of Glenarm, but the discrepancy between the alignment of much of the eastern terrace as shown on the 1832 Ordnance Survey map and that of 1857 strongly suggests it occurred. The theory is further supported by an 1830 illustration of the town by T.M. Baynes, published in Ireland Illustrated (London, 1831), which shows the two sections of the eastern terrace out of alignment, and by the fact that many of the buildings recorded in the 1833 valuation of the eastern side appear to bear no relation to those recorded in the 1859 valuation — as if all had been demolished in the intervening period. The age and condition grading used by the valuers in 1859 indicates that most of the rebuilt dwellings on the eastern side were twenty years old or slightly more at that date, pointing to much of the redevelopment having taken place in the mid to later 1830s. This fits with a remark in the Ordnance Survey Memoirs of 1835 that "some two storey houses of a tolerable description have been recently built in Glenarm, intended for the accommodation of lodgers during the bathing season." The western side of Altmore Street may have remained largely untouched by the changes of the mid-19th century, with some of the buildings visible today possibly pre-dating the 1830s, though some properties at the very southern end were cleared away for the construction of the Town Gate and absorbed into the estate grounds.

The site occupied by this house is shown as built up on O'Hara's 1779 map and on the 1832 Ordnance Survey map. On the 1779 map, the plot occupied by this house and the one immediately to the south are listed as the property of a John Richey. This John may have been a descendant or relation of Alexander Richey, "yeoman of Glenarm," who was granted a lease in December 1678 of a tenement with a frontage of 62 feet "on the south side of Altmore and west side of the street," with a requirement to "build a house of stone and lime." The length of this frontage suggests the 1678 lease refers to the same piece of ground held by the Richey family in 1779. Since the plot was under single ownership in 1779, the two dwellings visible today are likely to have appeared sometime after that date. The present house corresponds to a dwelling of the same dimensions recorded in the 1859 valuation notebook, where it is noted as "not new" — graded B, meaning at least twenty years old — and was leased to a Mrs Jane Beatty by James Hannah, Lord Antrim's agent, who himself lived a few doors to the south in the present numbers 27 to 29.

The incised door surround to the front elevation matches those on a group of three three-storey houses on the opposite side of the street (numbers 28 to 32), a group which appears to date from around 1835 to 1840 and is said locally to have been built for coastguard officers. Local tradition has suggested that the similar door surround here might indicate this house too was a coastguard officer's dwelling, though the only connection researchers could establish between all these properties is that all are recorded as belonging to James Hannah in 1859. A crossed-out note in the same valuation notebook suggests that the house immediately to the south (number 25) was at some point the home of a Lieutenant Sackville Thompson RN, while the 1835 Ordnance Survey Memoirs mention a "Lieutenant Servante RN, chief officer of the coastguard." This raises the possibility that the coastguard connection lay with the neighbouring property rather than with this house.

Despite the large modern flat-roofed rear return and the recent PVC conservatory, sufficient period character survives for the building to merit listed status.