Dyfi Furnace

Dyfi Furnace is a listed building with an associated structure, built from rubble stone and featuring a slated roof that is hipped at the west end around a square rubble stone chimney. The furnace itself is a tall, tapering stone structure with straight joints, and it includes a two-storey rear range that housed the bellows floor below the charging floor. This design is built into the bank to allow level access to the charging floor. The furnace has two small brick-lined porthole vents on three visible faces and numerous put-log holes. On the south side, there is a broad brick arch that tapers inward. The rear range has another porthole on the south side to the left, along with two slots at different levels, which have stone shelves above them, possibly remnants of lost lean-to roofs.

The ground floor features a very wide brick arch with a keystone to the left and a door to the right with a brick head. To the north, the roof extends slightly to shelter a large wooden water wheel, which is a reconstruction of a 19th-century wheel that was used when the furnace was converted into a sawmill. There is a part-blocked brick-arched opening to the left of the wheel that leads into the counter-weight room.

At the rear gable on the first floor, there are two openings with flat brick heads, one to the left that is glazed and a broader one in the center with timber doors, providing access to the charging floor. A buttress is located between these entries. Above, there are two fixed 8-pane windows with flat brick heads. Attached to the right is an outbuilding with a monopitch roof.

The lower floor of the rear range contains a broad brick and rubble stone transverse vault and a brick tapering arched opening to the west that leads into the furnace base, similar to the one on the south side. There is a stone shelf and steps on the rear north wall, along with three oak beams. Two slots have been cut into the vault for belts to drive machinery on the upper floor, which is linked to the 19th-century sawmill use. To the east is a narrower room with a higher floor level, identified as the former counter-weight room, featuring a transverse rubble vault. The upper floor has stone and brick paving, along with very large pine tie-beam trusses that include queen-struts and angled struts, supported by triple purlins.