St Mary’s is a Grade II listed church situated in the conservation area of Knighton Village. The church comprises chancel, nave, Lady Chapel, Chapel of Remembrance, north aisle, south aisle, tower with spire, sacristy, choir vestry, tower vestry, west and north porches. The tower is in three stages, the two lower of sandstone ashlar and the topmost, a fourteenth-century addition with the spire in white limestone.
The extension (1960-1962) is in natural stone and pre-cast artificial stone. In its earliest form the church is thought to have comprised only a small nave and chancel. The tower was probably commenced in the late thirteenth century and about 1350 the church was enlarged by the erection of a new nave of four bays, with a chancel, in the perpendicular style of architecture. After this addition the older part of the building served as the south aisle: it was rebuilt in 1894 (architect: Ewan Christian), the old stone being reused - this followed earlier restoration work c.1960 (architect: Henry Woodyer). The tower is in three stages, the two lower of sandstone ashlar and the topmost, a fourteenth-century addition with the spire, in white limestone, forming a striking contrast. It contains nine bells, the oldest of which bears an inscription with the date 1627. The north porch was built in 1876.
This little church which had served Knighton for many centuries proved to be too small for the suburb of a rapidly growing city after the introduction of a main line railway: accordingly it was enlarged in 1960-62, doubling the seating capacity. The extension was the work of a local architect, a parishioner, George A. Cope, and was planned to harmonise with the old building. It involved the rebuilding of the south aisle further southwards and the construction of a new nave, chancel and sanctuary. The old nave now forms the north aisle and lady chapel: its roof beams are thought to be of the fifteenth century date, and the new timber roof of the south aisle was constructed to match them. Much of the old stonework was re-used, but the new east end, the vestries and the west porch are constructed in precast material.
The foundation stone of the extension, laid in 1960, may be seen inside the west porch, and above its entrance is carved the traditional emblem of Mary Magdalen, the vase of ointment surrounded by tears of penitence. The interior of the church is light and spacious. Looking from the west end, the arcade on the left is Perpendicular work of the fourteenth century, while that on the right dates from the extension. Stained glass windows remain in the old north aisle.