20 George Square, Edinburgh

16 and 17 George Square are classical style houses built between 1767 and 1779 by James Brown, forming part of a terrace that now houses university departments, offices, and residences. The terrace underwent numerous alterations and additions, including the enlargement of attic storeys with new dormers, completed by William Smith and Sons in 1882, which also included a mansard roof at numbers 16 and 17. Other notable alterations were made by James Bow Dunn in 1890 for number 21, Arthur Colville & Co in 1911 for number 18, and James Jerdan in 1896 for dormers and an oriel window at the rear of number 20. Reginald Fairlie extended the rear of number 26 in 1912, and the University of Edinburgh Department of Works made internal alterations and additions to numbers 27 and 28 in 1953.

The houses are predominantly four and five stories tall, with three and four bays, and are constructed of squared snecked pink and cream Craigmillar rubble sandstone with blue whin pinnings for numbers 16-22. Numbers 23, 23a, and 23b, as well as 24-27, are built from coursed rubble with snecked ashlar dressings, while numbers 28 and 29 feature Craigleith ashlar. The terrace is set on sloping ground, forming the west side of George Square. Architectural features include architraved doorpieces for numbers 16-22 and 28, Roman Doric doorpieces for numbers 23 and 25-27, an Ionic doorpiece for number 24, and raised long and short quoins for numbers 25-27. Number 29 has arched openings at the ground floor with a plain doorpiece and an elaborate fanlight, while numbers 23a and 23b have arched openings at the ground floor with a central Venetian window.

The windows primarily feature 12-pane glazing in timber sash and case style, with some large pane glazing present. The buildings also have tall corniced gable stacks with yellow clay cans. Most interiors were observed in 2015, revealing many alterations and connections but still retaining outstanding elements of Georgian interior design, including staircases with decorative iron balusters and timber handrails, marble and timber chimneypieces, panelled timber doors, fine decorative cornices, some timber dadoes, and notable late 19th-century features.