Ffactory Pen-y-caerau is named on all three editions of the 25-inch O. S. map, with a 240 metre long leat feeding a millpond to the north-east of the buildings. The two-storey factory building, constructed of rubblestone with brick window dressings and arched brick lintols, has lost its roof and upper floor and the walls have been reduced to first floor height. A workshop with corrugated iron roof has been constructed inside the south-east end. There is no evidence of the position of a waterwheel or turbine, though the position of the millpond is still visible.
An old photograph shows workers outside the mill with two great spinning wheels and patterned blankets. The house, now a private residence, is said to have been a shop, and the attached wing at its south-west end is said to have been built as a knitting workshop.
W J Crompton, RCAHMW, 12 August 2010.