Avon Crescent Substation

The Avon Crescent Substation, built in 1905-1906, was designed by L G Mouchel of the Hennebique Concrete Company. It is an electricity substation constructed using a reinforced concrete internal framework based on the Hennebique system, with shuttered concrete elevations. The roof was originally patent glazing, but has since been replaced with corrugated covering.

The building occupies an irregular, triangular plot situated between Avon Crescent and Cumberland Road, its shape designed to best fit the location. It is a double-height structure with a carefully designed classical facade, marked with ashlar scoring, while the other elevations are largely plain and show the shutter marks from the construction process. The principal north-east elevation, facing Avon Crescent, features a symmetrical arrangement of five double-height, Renaissance-arched window openings, now blocked, complete with concrete hood moulds, keystones, and sills. Flanking these are wide, slightly projecting bays, each with a flat-arched doorway. The bay on the right still has a roller shutter, but is missing its keystone. Both bays have a blocked arched window above the doorway. A cornice and parapet run along the top. The elevation continues as a single storey to the left, incorporating a blocked oeil de boeuf window and a second similar window on the corner elevation facing the road junction. The cornice extends along the curved south-west elevation. The building originally had a pitched, glazed roof over the machine hall and flat roofs at the angles, and a conical ventilator remains on the roof.

The main machine hall is a large space, originally lit from above by patent glazing and the arched windows of the principal elevation. The floor is believed to retain evidence of six low platforms used for converters, with wrought iron grilles above the cable and transformer subways. A concrete framework supports a manually operated gantry crane. Cantilevered concrete galleries, connected by a steel bridge, previously housed the switch gear and are thought to retain some decorative wrought iron balustrades and oak handrails. Areas of original white and green tiling are understood to remain, along with some internal doors, and the roof is supported by steel trusses.