15 Market Place, incorporating part of the Church of St Mary

15 Market Place is a house with a later ground-floor shop, dating from the late 18th century or early 19th century, with some alterations made in the late 20th century.

The building is mid-terrace, featuring a front rectangular block and a rear rectangular block that is slightly displaced to the right. The front elevation is constructed of red brick that has been rendered, while the rear block is made of stone rubble. The roofs are covered with Welsh slate.

The exterior of the four-storey, single-bay building has a shallow slate roof. Each of the upper floors has a large window, all fitted with replacement unhorned eight-over-eight sliding sash windows. The ground floor features a shopfront with three fascia brackets and a half-glazed door to the right, designed in a late 19th-century style, but likely a late 20th-century replacement.

Inside, the rear wall of the front block includes parts of the north arcade of the Church of St Mary. Investigations conducted in the late 20th century uncovered medieval squared blocks that are remnants of the arcade wall. Notably, there is a 13th-century octagonal arcade pier made of diagonally-tooled sandstone ashlar, which has a modified hold water base and a capital with a roll moulding and a moulded abacus. Additionally, there is a two-centred arch composed of two chamfered orders, along with traces of a second arch. Both arches of the 13th-century arcade have been blocked up, with lancet windows inserted into the blocking; these windows have simple chamfered surrounds and shouldered pointed rear arches.