Cefn Coed Colliery Engine House Range and Steam Capstan Engine

The range comprises three buildings – a compressor house at the northern end, a winding engine house in the centre, and an electrical house at the south – forming a continuous group. All three buildings date to the 18th century and have gabled slate roofs running east to west, constructed of red brick. They feature metal multi-pane windows with arched concrete lintels, set within tall recessed panels of stepped brickwork. Circular openings punctuate the gables.

The compressor house, the first and smallest building, originally housed two compressors, one of which, a Bellis and Morcom compressor from 1946, survives. The east end is now used as an exhibition area. The central winding engine house has a western gable facing the No 2 headframe, with three openings: two metal-framed windows with 6x8 panes, and a third that was originally full height with an arched top to take winding cables to the headframe, now bricked up. The eastern gable features a pair of similar windows and a central arched double doorway with glazed panelled doors, alongside a circular window in the gable. Inside, a large horizontal twin-cylinder winding engine, built in 1927 by Worsley Mesnes Ironworks of Wigan, remains; this features cylinders on either side of the winding drum, with a bore exceeding 80cm and a stroke of over 1.5m. The drum itself is approximately 3m wide and nearly 5m in diameter. The floor is laid with brick paviors in a herringbone pattern. The southern, and largest, electrical house is slightly later and incorporates blocked-up windows from the winding engine house in its northern wall. It conforms to the others in architectural detailing, although four bays have had windows blocked in the late 20th century. High-level windows are open in the western gable. A single-storey extension at the eastern end, formerly open, is now blocked due to safety concerns.

Immediately beyond the western gable of the winding engine house stands a steam capstan engine, a horizontal single-cylinder capstan type, manufactured in the 1920s by Llewellyn and Cubitt of Ton Pentre, Rhondda. The electrical building originally housed electricity generating equipment, remnants of which remain, although the interior has been cleared. A 2.4-metre-high gallery survives along the southern wall, supported by iron columns.