Pentrefelin and Bwthyn-y-felin

Pentrefelin and Bwthyn-y-felin is a rectangular rubble building situated on a slope, featuring a three-storey main elevation and a two-storey rear. The building has red brick segmental heads over its openings and a renewed hipped slate roof with a single squat chimney located to the left of the center. The front consists of four bays, with a two-bay mill section on the right, now known as Pentrefelin, and the miller's accommodation on the left, referred to as Bwthyn-y-felin. The mill section has a wide entrance on the right, featuring a pegged wooden frame and a modern boarded door. The domestic section has an entrance on the left with a modern door as well. The building includes slightly-recessed modern sash-type windows with tilting upper sections, consisting of 12 and 9 panes, along with additional modern windows on the side and rear elevations with 6 to 12 panes.

At the rear, there is a single-storey gabled porch on the left, which has a former loading bay above that is now a fixed sash window. To the right, there is a single-storey former bake-house projection at the corner, which has a partly hipped roof and modern doors.

Inside, there is a large internal overshot waterwheel with a diameter of approximately 6 meters, which is partly disintegrated as of June 1996. This waterwheel is connected to a secondary wheel that operates the vertical driveshaft, and the cast iron wheel has lost its paddles. There is an iron toothed crown wheel on the first floor with associated layshafts and secondary drives. The mill contains three large pairs of stones, two of which have modern boxing, and mostly renewed timber hoppers. It also features pulleys and wheels for the mill pond sluicegate and sack hoist.

There are two large panelled grain cupboards with raised and fielded panels on the sides and hinged fronts. The cupboard on the right is the earlier of the two and bears incised graffiti dates of 1795 and 1799, with wooden hoppers above; the right cupboard has been renewed. Additionally, there is a later 19th-century pulley-driven grinding machine with a hopper, consisting of a Christy and Norris Disintegrator and a Eureka smut and separating machine by Howes Babcock and Co., New York, from the 1865 model. The roof is supported by two king post trusses.