Turbine Hall, Ben Cruachan Hydro Electric Scheme

The Turbine Hall at the Ben Cruachan Hydro Electric Scheme was designed by James Williamson and Partners, with George Rennie serving as the resident engineer for the North of Scotland Hydro Electric Board technical panel and J B Armstrong as the architect. Constructed between 1959 and 1965, this monumental underground chamber features a barrel-vaulted design carved from solid bedrock, complemented by a long sloping vaulted access tunnel. The turbine hall itself is an impressive 36 metres high and 90 metres long, with a viewing gallery located in the northeast corner at the upper level and a concrete-lined vaulted roof.

Inside, the northern side of the hall is supported by regularly spaced columns that hold a track for overhead gantry cranes. The floor is tiled, and the south wall is equipped with control panels, above which is a large inlaid timber mural by Elizabeth Faulkner positioned in the southeast corner. The remainder of the south wall features alternating timber panels and acoustic baffling panels made of concrete, arranged in regular geometric shapes. Offices are located to the south, including a control room at the upper level that has a projecting faceted timber and plate glass window overlooking the turbine hall floor. The transformer room and surge shaft are situated at the far south end. The lighting in the hall is provided by large overhead panels, with lights enclosed by panelled timber wings that cantilever from a large central beam. The entrance area is finished with matt grey square ceramic tiles, while replacement tiles are used within the turbine hall.

The access tunnel is a vaulted vehicular passage that extends for 1 kilometre from the entrance, culminating in a round arched entrance to the turbine hall lined with rectangular slate tiles. A pedestrian entrance to the offices is located directly adjacent to the left (east), featuring split slate tiles that form an apron around the doorway.