54 High Street, Ayr

54 High Street in Ayr is a four-storey, three-bay tenement building designed by John Mercer in 1880, featuring Renaissance details and a ground floor shop. The exterior is finished in polished red ashlar with banded rustication, except for the third floor. Notable architectural features include a cornice above the shopfront, a dentilled cill course on the second floor, a band course on the third floor, a triglyph entablature at the cornice, and a balustraded parapet with dies.

On the southwest elevation, banded pilasters frame a modern shopfront at the ground level, which includes a central two-leaf aluminium door and flanking shop windows. The upper floors have regular fenestration, with cavetto round-arched recesses for the first-floor windows, a bowed iron balcony for the central window, and balustraded aprons with iron balconies for the side bays. The second-floor windows have segmental-headed architraves, balustraded aprons, and bracketed cornices. The third-floor windows feature lugged architraves and bracketed iron balconies.

The southeast elevation, facing Old Bridge Street, has five bays divided by double banded pilasters at the ground level, which also includes a modern shop and shop windows. There is a timber entrance door on the outer right and a large plate glass square fanlight. The upper floors have regular fenestration similar to the southwest elevation, but with plain aprons and iron window guards on the third-floor windows.

The first floor features French windows, while the second and third floors have four-pane timber sash and case windows. The roof is a grey slate piend, with decorative corniced wallhead stacks and square cans. The interior was not seen in 1998.