Sunday School, St Mary's Church, Dunderg Road, Macosquin, Coleraine, Co. Londonderry

A T-shaped single-storey rubblestone church hall dated 1851, located on the south side of Dunderg Road in Macosquin. Originally constructed as a Sunday school, the building now serves as a parish church hall.

The hall is built of random rubblestone with red-brick dressings and lime pointing. It features a pitched natural slate roof with angled ridge tiles and a replacement red-brick chimneystack. Decorative bargeboards adorn the gables. The principal northwest elevation comprises a central projecting gable with flanking bays, each containing a window. A datestone inscribed "A.D 1851" is positioned above the gable window. The gable also displays 6/6 timber sash windows with horns in red-brick surrounds with projecting stone sills. A replacement timber-sheeted door is located to the left cheek. The pointed-arched window to the northwest gable is a metal-margined diamond lattice design with two lights and a quatrefoil above, set in a cement-rendered surround with concrete sill. The southwest gable contains two windows. Windows throughout are replacement 6/6 timber sash with horns in red-brick surrounds with projecting stone sills. Plastic rainwater goods are fitted, with a red-brick eaves course featuring alternate projecting headers.

The building has been refurbished with modern additions: a glass entrance lobby has been added to the northeast gable, and a single-storey cement-rendered flat-roof extension extends to the rear. These alterations have resulted in some loss of original detailing and integrity, though the building retains its essential character.

The hall is situated on a square plot with cemetery to the south side of Dunderg Road. The site is bounded to three sides by rubblestone walling. To the front is a rubble-stone wall with sandstone coping, partly topped by decorative replacement cast-metal railings. Square sandstone piers with chamfered caps support replacement cast-metal entrance gates. The cemetery to three sides contains a variety of headstones dating from the first part of the nineteenth century.

Historical context: The building represents the second schoolhouse constructed at St Mary's Church. The first schoolhouse, recorded on the 1830-31 Ordnance Survey map, stood to the north side of the church and was a simple rectangular structure. The Ordnance Survey Memoirs of circa 1835 documented the moral benefits of the Sunday school, noting improvements in the parish arising from Sunday school influence and increased Bible circulation. The current building was completed in 1851, though construction commenced by at least 1850, as it appeared on the 1849-50 Ordnance Survey map. The 1856 Griffith's Valuation recorded the schoolhouse as administered by the Church Education Society, valued at £4. The layout remained unchanged on subsequent Ordnance Survey maps through 1949, with the valuation remaining at £4 until 1930. Under the First General Revaluation of property in Northern Ireland in 1935, the value increased to £16. By the second revaluation (1956-72), the value had risen to £20. During this period, the former schoolhouse was converted to use as a church hall, a function it continues to serve.

The building was listed in 1977 alongside the adjoining St Mary's Parish Church. In 2010, the former schoolhouse underwent refurbishment with the installation of a new kitchen and computer suite. A modern glass-fronted extension was constructed to connect the hall and church, creating an entrance porch between the formerly separate buildings. This work, undertaken by J.A. Gamble Construction, cost approximately £105,000 and was funded by parish fundraising. The former school now houses the minister's office, a small meeting hall, and the kitchen and computer suite from the 2010 refurbishment.

The building possesses important group value with the adjoining St Mary's Parish Church, together forming a well-preserved group that makes a significant contribution to the historic rural landscape of the Coleraine district. It is of considerable local interest and social importance to the surrounding community.