Outbuilding with Mill Wheel at Dyffryn Llynod

The outbuilding at Dyffryn Llynod is an earlier range of structures that features a later 19th-century iron water wheel. It is constructed from rubble stone, which has been whitewashed on the front, and is topped with a long slate roof. The building is mostly two stories high, but the southern end includes a five-bay barn.

Starting from the southern end, there is a door leading into the barn, followed by another door, and outside stone steps that lead to an upper loft door. Next, there is a door to a stable, with a window on each side and corresponding loft windows above. This is followed by another door and two round arched cart entries, which have a loft window above and between them. The northern end wall features outside steps leading to a loft door.

On the rear side, there is a door that opens into the upper level of the barn, followed by the large overshot water wheel, another door to the loft, and a door that breaks the eaves, with a window further to the left.

The building has a collar-truss roof.