Barn Immediately South East of Billany Farmhouse

This building is a barn and horse engine house located immediately southeast of Billany Farmhouse, dating from the late 17th century. It is constructed of cob and stone rubble, with the outshuts and horse engine house made entirely of stone rubble. The barn features a steeply pitched corrugated iron roof, with a gabled end on the west side and a hipped end on the east side.

The barn has a large rectangular plan with doorways on either side of the center leading to the threshing floors. The lower left (east) section has been partitioned off and has a floor inserted. There are 19th-century outshuts added at the rear left of center and at the front right, along with a 19th-century horse engine house at the rear right. A late addition is the outshut at the center of the front.

On the exterior, the north front has two cart entrances on either side of the center. The main roof extends over the later outshuts and provides canopies over the cart entrances, with the right-hand canopy supported by wooden cantilevers. At the rear (south), there is a round-ended 19th-century horse engine house on the left with a semi-conical scantle slate roof, and on the right, a 19th-century outshut with a lean-to roof.

Inside, the roof features 13 closely spaced trusses, with one missing at the west end. Some of the principals have slightly curved feet and all rest on the wall plate, with mortice and tenoned apexes and collars that are halved, lapped, and pegged to the principals. There is an inserted partition wall at the east end, where the floor has collapsed. The engine house contains a large beam.