18 Crescent Street

17 and 18 Crescent Street, located in Penygloddfa, Newtown, are three-storey buildings with a cellar, designed as a mirrored pair of former back-to-back houses. They feature a Flemish bond brick front and a gently pitched slate roof, with the roof of No 17 being old and having a lead ridge, while No 18 has a new roof. The buildings have deep boarded eaves and a central chimney stack, with an additional stack serving the tunnel passage bay at No 19.

The second floor has shallow eight-pane sash windows, which may have originally been slate hung. The first and ground floors are fitted with sixteen-pane sash windows. All windows have stone lintels and sills with plain reveals, and there are cellar openings below, similar to the bay over the tunnel passage. The doorways are offset at the outer ends and have plain doorcases with corniced brackets supporting gabled dripboards, featuring original six-panel doors.

The tunnel passage entry to the former Jones's Court at the right end has a stone lintel. The rear elevation is slate hung, with No 17 retaining original small-paned iron windows, while No 18 has modern windows. Both buildings have deep boarded eaves.