14 Cassillis Street, Ayr

12 Cassillis Street in Ayr is a mid-19th century pair of mirrored houses, two stories high with a basement and an attic (for No 14). They are part of a terrace and are constructed from painted coursed, squared sandstone, with exposed sections on the south and west elevations. The building features a ground floor band course, an eaves course, a cornice, a blocking course, and painted strip margins. The windows have architraves and are corniced at the ground floor.

On the east (entrance) elevation, there is a central stepped platt that oversails the basement, leading to a double doorpiece that is pilastered, corniced, and topped with a block pediment. The entrance has glazed timber doors with letterbox fanlights, and there is a glazed timber door aligned below at the basement for No 12. Above, there are two single windows at the first floor. The ground floor has single windows flanking the entrance, with a glazed timber door to the basement on the left. There is a flat-roofed two-light dormer at the attic on the outer left.

The south (side) elevation is two bays wide, featuring single windows of varying sizes at the basement, ground, and first floors in the center, and a single window at the ground floor to the right.

The upper sashes of the timber sash and case windows have four-pane glazing, while the lower sashes have two-pane glazing. The roof is covered with grey slate and includes rooflights, stone skews, corniced stacks, and both circular and polygonal chimney cans.

The interiors were not seen in 1998. The property also has ashlar copes topped with iron railings leading to the stepped platt and basement on the east elevation, along with an iron gate to the right.