1 Northumberland Street, Edinburgh

1 Northumberland Street in Edinburgh is an impressive terraced tenement building designed by architects Robert Reid and William Sibbald between 1804 and 1819. This four-storey structure features a basement and has five bays. Notable architectural details include a band course below the principal, first, and third floors, projecting cills on the first and second floors, and a cornice with a blocking course at the third floor. The entrance is accessed via ashlar steps and a platform that overhangs the basement.

The south elevation, which is the principal façade, features a round-arched doorpiece at the principal floor, consisting of a panelled timber door topped with a semicircular fanlight. The building has regular fenestration across all floors, although there are blind windows in the penultimate bay to the right and in the outer right bay on all floors. The basement area is flagged.

The east elevation, which connects to 20 and 22 Nelson Street, also has five bays. It includes a panelled timber door for the common stair, with a blind rectangular fanlight above, located at the principal floor. The remaining bays have regular fenestration at the principal floor and above, with an altered window in the penultimate bay from the left at the principal floor, featuring a timber mullion. A continual cornice at the second floor returns and terminates at the corners. There is a three-bay pilastered shop front on the right side of the basement, which includes a plate glass window flanked by two six-panel timber doors with plate glass rectangular fanlights and a modillioned cornice.

The north elevation adjoins another terrace, which is listed separately (24-28 Nelson Street), while the west elevation also adjoins a terrace that has its own listing (3 Northumberland Street).

The building predominantly features twelve-pane timber sash and case windows, with iron window guards in three bays to the left at the third floor of the south elevation and in two bays to the left at the third floor of the east elevation. The roof is covered with grey slate in an M shape, and there are cast-iron rainwater goods. The chimney stacks are made of polished ashlar, with one being broached and shouldered, and another rendered and shouldered, all coped with circular cans.

The interiors were not seen in 1997, but there is some evidence of working panelled shutters. The property is also adorned with ashlar copes topped by iron railings featuring spear-headed balusters and urn finials. Additionally, there are cast-iron lamps mounted on the railings, complete with glass globes.