18, Sion Hill

No. 18 Sion Hill is a house built around 1795, constructed from limestone ashlar with a slate roof. The building features a three-unit plan and has a late 19th-century shallow off-centre rectangular block added to the rear. The front of the house is plain and two storeys high, with a central door that has a hood supported by heavy scrolled brackets, and a garage to the left. The first floor has three sash windows, and there is a raised parapet at the centre flanked by lateral stacks. The ground floor is painted.

The rear garden elevation is more elaborate, consisting of six bays and two storeys with a lower ground floor that takes advantage of the sloping site. The centre is masked by an addition, and there are six-over-six pane sash windows with sun-blind boxes on the ground and first floors, while the addition has plate glass. To the right, there is a conservatory with an eight-over-eight pane window facing south. The first floor features lozenge-enriched panels on the outer bays. The attic storey has an eight-over-eight pane arch-headed window set within a unique four-sided scalloped gable with a finial, along with a moulded cornice to the parapet that has decorative urns above the outer bays.

Inside, the house has six-panel doors and a central stone staircase with moulded treads, stick balusters, and a mahogany rail. According to the Bath Preservation Trust Interiors Survey from 1988, there is a significant survival of original fittings, including a dining room chimneypiece with classical figures in niches on the frieze, alcoves with reeded surrounds, a glazed wall cupboard with composition decoration, panelled shutters, and original water leaf decoration on the plaster cornice. The drawing room features a chimneypiece with Adamesque urn and garland decoration, and there is a dresser in the kitchen.