Calton House, 24 Dean Street, Edinburgh

Calton House, at 26-28 Dean Street, Edinburgh, comprises a former Secession Church dating from circa 1826, along with later additions and alterations. The main block is a symmetrical three-storey, three-bay rectangular building, advanced centrally within a terrace (No 30). The front of the building is painted harl at ground level, with painted render above; sandstone rubble forms the sides, which are partly squared and coursed. A raised base course and string course separate the ground and first floors, and there are corniced eaves.

A former school designed by Robert Wright in 1826 adjoins the building to the left. It was converted for school use circa 1844, with subsequent additions and alterations. This part is an irregular single-storey, six-bay grouping which forms the end of the terrace, composed of a symmetrical three-bay block to the right (Nos 26 and 28) and an asymmetrical, three-bay block to the left (No 24). The front of the school is sandstone ashlar, with red brick to the side, corniced eaves on the right, and corniced and pendant-bracketed sandstone canopies to the front.

The north-east side elevation features a square-headed opening centred at ground level, with a segmental-arched window above it, and a single-storey addition projecting to the outer left. The front of the building has 12-pane glazing in timber sash and case windows. A grey slate, piended roof tops the structure.

The south-west side elevation originally featured a four-bay nave with regularly spaced, segmental-arched windows in each bay. These windows generally have lying-pane glazing, with hoppers to the front. This elevation also has a grey slate, piended roof.

The north-west (entrance) elevation of the former school displays a large, bipartite window centred in the three-bay block to the right, with a full-width canopy above. Flush-panelled timber doors flank the ground level, with a blocked fanlight to the right and a small-pane fanlight to the left, both surmounted by canopies. A lower, three-bay block is to the left, featuring a two-leaf timber door in the right bay, with a fanlight and surmounting canopy. Single windows occupy the remaining bays to the left. A single-storey addition is recessed to the outer left.

The north-west (entrance) elevation of the former church presents a projecting central bay with a large, round-arched entrance at ground level, containing two-leaf, part-glazed doors with flanking side-lights, featuring stylised border glazing. A decorative round-arched fanlight sits above the entrance, topped by a keystone. Two square-headed windows are above the entrance at first floor level and a single, segmental-arched window is centred at second floor level. Large, round-arched windows flank the entrance at ground level, with square-headed windows aligned above them, and segmental-arched windows further aligning above. A deep-set two-leaf boarded timber door is located at ground level to the outer left. A single-storey garage is adjoined to the right.

The interiors were not inspected in 1999.