Factory ('Morelli's Ice Cream'), Eglinton Lane, at rear of 4 Dunluce Avenue, Portrush, Co Antrim

Small, plain single storey factory building with curved Belfast Truss roof, dating from around 1900. Located on the south-east side of narrow Eglinton Lane at the rear of 4 Dunluce Avenue, close to Portrush town centre, the building may originally have been an outbuilding associated with the neighbouring house before its conversion to ice cream production.

The structure is roughly L-shaped in plan. The main section is rectangular, measuring approximately 23 metres by 6.5 metres, covered by the curved Belfast Truss roof. A smaller, roughly triangular flat-roofed section branches off to the north-west, creating the L-shape. Because of this configuration, only the right-hand half of the north-west elevation and the north-east gable of the Belfast Truss roofed section are visible from outside. Both are finished in painted roughcast. The gable is blank. The north-west elevation contains three windows of varying sizes with modern frames and a timber-sheeted pedestrian doorway, with a modern up-and-over metal vehicle doorway at the far right. A deep timber-sheeted eaves course runs beneath the curved roof, which is covered in felt.

The building has been substantially altered over the years and not all the original Belfast Trusses have survived.

The Belfast truss was developed in the mid-nineteenth century to meet demand for efficient, lightweight long-span roofs brought about by the Industrial Revolution. The first known reference to a curved wooden felted roof structure supported by bowstring girders appears in an 1866 advertisement by the Belfast felt-maker McTear & Co. in the Dublin Builder. McTear continued manufacturing trusses until closing in 1908. A second Belfast felt supplier, Anderson & Co., began producing trusses to a different design in 1886, launching their Mark II version in 1896, promoted for maximising long spans while maintaining light weight. This model was subsequently adopted by other companies and is widely referred to as the Belfast truss, a term applied generally to all timber bowstring trusses where internal bracing members meet on the top curved member rather than on the bottom, as was conventional.