Building Facing Car Park At South East End Of Thorp Arch Mill (Premises Of Blanella Limited

This is a late 17th-century water mill, significantly raised in the 18th century and altered in the 20th century, now incorporated into a factory complex. The building is constructed of coursed, squared magnesian limestone with Welsh slate and stone slate roofs. It has two storeys with a basement and attic, comprising three cells, with a shorter wing to the rear right.

The basement, partially buried due to ground infilling, has three doorways. The doorway to the left features a deep, chamfered lintel with a triangular soffit. The central doorway has a deep, 17th-century lintel which was cut out to form a shallow segmental arch and bears the date 1867. The doorway to the right is chamfered and has a basket-arched lintel. Above the doorways are three boarded, double-chamfered windows lacking mullions. The first floor has two casement windows set beneath segmental arches, a small window to the far right, and a double-chamfered, two-light window without mullions on the left. The walling above these windows is of a later date and includes two half-dormers to the attic floor.

The rear elevation exhibits similar fenestration. A corbelled 17th-century external stack is centrally positioned and capped off. A wing on the left has a stone slate roof. The left return has a blocked basement opening with a wooden lintel, an incomplete double-chamfered window on the right, and a 20th-century casement window to the gable within a corniced 18th-century opening. The right return has later external steps leading to a wide, chamfered and quoined doorway with a cambered lintel and a raised keystone. A high-level doorway provides access to a bridge, which is not listed, and forms a link to a range of adjacent buildings.

The central cell of the basement, filled with debris in 1987, contains buried front windows. The left cell houses a water wheel with a cast-iron hub and remains of wooden spokes. Later floor and roof structures are present inside. The mill was originally built as a rape-seed oil mill and was later used for paper and bobbin manufacturing. Ralph Thoresby of Leeds noted in his diary of 1691 that he viewed the newly erected rape-seed mill at Thorp Arch.