21 Gayfield Square, Edinburgh

22-23 Gayfield Square is a symmetrical terraced double tenement block designed by Hugh Cairncross in 1808. It is a four-storey building with a basement and features a seven-bay elevation facing Gayfield Square. The exterior is made of droved ashlar, with coursed, squared rubble and droved margins at the basement, and coursed rubble with dressed margins at the rear. There is a dividing band between the basement and ground floor, as well as an eaves course, and the building has regular fenestration.

The principal elevation has three central bays on the ground floor, with individual steps and a platform leading to the doorway. The doors are timber-panelled and feature rectangular fanlights with three-light glazing in the central bay and umbrella glazing in the flanking bays. The third-floor windows have cast iron balconettes, except for the central bay.

The rear elevation is six bays wide, with a slightly recessed three-bay section on the right. There are small square windows in the fifth bay from the left, excluding the second-floor opening.

The windows are timber sash and case with 12-pane glazing, while the smaller windows on the rear elevation have four-pane glazing. The roof is an M-shaped design with a valley gutter, covered in grey slate, and features stone skews and skewputts. There are mutual ridge stacks at the outer left and right, along with two central ridge stacks, all of which are corniced and made of coursed rubble with droved dressings and circular cans.

The property is bordered by cast iron railings with spear-head and urn finials, set in stone copes that edge the basement recess, along with plain railings that edge the steps and platforms.