18-20 Dundas Street, Edinburgh

18-20 Dundas Street in Edinburgh is a four-storey and basement terraced tenement, likely designed by Thomas Bonnar in the early 19th century. The building is constructed of broached ashlar sandstone, featuring V-jointed stonework at the principal floor. It has a band course between the basement and principal floors, as well as between the principal and first floors. The first and second floor windows have projecting cills, and there is a continuous cornice at the second floor that continues as a band course on the north elevation. The third floor has a cornice and blocking course. The entrance features ashlar steps and platts that extend over the basements.

On the principal elevation, there is a panelled timber common stair door with a geometric rectangular fanlight located in the penultimate bay from the left at the principal floor. To the right, there is a glazed two-leaf timber door with a round-arched doorpiece and a radial, semicircular fanlight in the penultimate bay from the right. This door is flanked by a pair of two-bay shop fronts with pilasters and cornices, each featuring two-leaf timber doors, plate glass rectangular fanlights, and plate glass windows. The upper floors and basement have regular fenestration, with blind windows at the outer right on all floors.

The north elevation, facing Northumberland Street, has five bays, including a panelled timber door with a four-panel rectangular fanlight in the penultimate bay from the left at the basement. The remaining bays at the basement contain windows, and the upper floors have regular fenestration.

The building predominantly features 12-pane timber sash and case windows, a grey slate M-roof, and cast-iron rainwater goods. The wallhead stacks are shouldered and coped, topped with circular cans.

The interiors were not seen in 1997, but there is some evidence of working panelled shutters. The railings consist of ashlar copes topped with cast-iron railings that have spear-headed balusters and urn finials.