Former Llanbradach Colliery engineering shops

Consisting of 3 parallel gabled ranges oriented N-S. Of rubble stone with rock-faced dressings and with corrugated iron roofs. The S end, facing the yard and the former shafts, has 3 symmetrical gables with centrally-placed round-headed doorways flanked by tall round-headed windows (all windows blocked with some windows inserted into the blockings) and with round ventilators above, retaining some original louvres. The side walls are 6-bay with round-headed windows. On the E side the windows are partly blocked but retain iron-frame radial glazing. On the W side they are blocked. On the W side is a passage spanned by girders attached to the upper revetment wall. The rear elevation has round-headed windows, 3 to each range.

Traces of the narrow-gauge railway survive in the floor of the W range. The ranges are separated internally by rubble-stone partition walls. The roofs have wrought iron trusses similar to the engine hall.