20 Dartmouth Row

20 Dartmouth Row is a late 17th-century house that underwent alterations in the 18th and early 19th centuries. The building is finished in stucco and features a slate roof that is hipped at both the front and rear, although the front is concealed by a parapet. Brick chimneystacks are present.

The house has three storeys and three bays on the east side, while the west side has three storeys and two bays. The north bay is lower, indicating it was built at a different time than the rest of the house.

On the principal east front, there is a stone parapet, and each floor has three 6-over-6 pane sash windows set in near-flush box frames. The windows in the north bay are positioned lower than the others. The entrance features a ten-panelled door located in the north bay, sheltered by an early 19th-century elliptical-arched wooden porch. This porch has a leaded roof adorned with circular and teardrop motifs in the tympanum, supported by delicate arched trellis panels. An attached stuccoed boundary wall with a stone coping and two square piers flanks a pedestrian entrance; one pier is small with a flat coping, while the other is larger with a pyramidal coping.

The rear or west side has a hipped roof over a wide three-storey south bay, which includes a cambered-headed tri-partite sash window with 12-over-12 panes on the second floor. The first floor features a multi-pane curved bay with a moulded cornice and base, supported by carved brackets, and the ground floor has a glazed verandah. The north bay, which is lower and narrower but also three storeys high, has a penticed roof, a 6-over-6 sash window on the second floor, and a slightly projecting two-storey extension with a flat roof and a 6-over-6 pane sash window on the first floor.

The interior was not inspected in 2015, but according to a 1930 RCHME Survey, the front ground floor room includes panelling in two heights with a dado-rail and coved cornice. A round arch with fluted pilasters separates the passage from the hall, with the soffit carved with a bird and scrolled foliage. The first-floor rooms have plain panelling.