Block alongside Firth Street at Commercial Mills

The block alongside Firth Street at Commercial Mills was built in 1864 and is constructed of hammer-dressed stone with a pitched slate roof and coped gables. It stands three storeys tall and features stone brackets supporting the gutter. The road-facing side has thirty-eight ranges of industrial windows with glazing bars. In the center, there is a tower that rises two storeys higher, flanked by four ranges of windows on Commercial Street, which include two oculi in the gable ends. The ground floor windows are round-arched, adorned with vermiculated voussoirs and a continuous moulded impost band. The tower has a hipped roof with a moulded and bracketed cornice. The entrance is round-arched with hollow chamfered surrounds, and the jambs and voussoirs are alternately vermiculated and made of ashlar, featuring spur stones. Above the ground floor, there is a frieze and moulded cornice topped with a pediment-shaped blocking course that is inscribed with "Commercial Mills" and "1864". The first floor has two segment-headed sash windows set within a segment-headed panel with rusticated voussoirs, with every alternate window being vermiculated.