Old house, with attached byre and barn at Trebanog Fach

This is a two-story house with an attached byre (farm building) at its downhill (south) end and a barn at the uphill (north) end, dating from the 17th century. The western side of the house is roughcast, while the eastern side is built of whitened rubble stone with exposed boulder foundations. Most windows retain their wooden frames, although the glazing has been removed. The roof is now covered with replacement slate and features a reduced stone chimney stack on the downhill gable end.

The western facade has a later doorway inserted to the right, where the outline of a former gabled porch is visible in the render. A window to the left of the doorway is likely from the 19th century and was originally a sash window. Further to the left is an original 17th-century parlour window with a decorative drip stone. The upper story has two windows beneath the eaves, with the right-hand window, above the doorway, being a two-light casement. The rear (eastern) elevation has two doorways on the lower story. The left-hand doorway, originally a window, retains a 17th-century hood mould that abuts an outshut. The doorway to the right is later and has brick jambs. Both doorways have boarded doors. An inserted or enlarged window is present in the upper story. A small window is located in the outshut at the left end, which houses the staircase.

The lower byre is constructed of rubble stone and has a concrete tile roof, with openings supported by wooden lintels. Its western wall is continuous with the house’s wall but is separated by a vertical joint. A full-height doorway with a split boarded door is on the left side, a central former doorway has been converted to a window, and a further doorway is at the right end. The eastern side has three doorways, retaining boarded doors on the outer sides, along with a two-light window on the right.

The barn is built of rubble stone and has a galvanised metal roof. It is narrower and lower than the house. A central full-height doorway with replaced boarded doors is on the western side, flanked by former loft openings, also with replaced boarded doors. A straight joint further to the left indicates that the granary at the upper end was constructed later. The granary has a loft doorway with a boarded door in its gable end, accessed by external steps. The eastern side has a central doorway narrowed with brickwork and a full-height doorway to the granary with double doors.

The original layout of the house has been preserved. The hall has a ceiling with stop-chamfered spine beams with run-out stops to the joists, and a fireplace with a timber lintel. Surviving posts indicate a former screen between the hall and a parlour and pantry at the uphill end. To the right of the hall fireplace is a boarded door, with a round-arched doorway leading from the byre, which represents the original house entrance. A doorway to the staircase is located to the left of the fireplace, retaining its original wooden Tudor surround with bar stops. The original stone staircase has been partly replaced with wooden treads. A steep staircase from the upper story to the attic also remains. The attic floor has been removed, leaving the upper story open to the roof, which is a three-bay structure with collar-beam trusses, although one collar has been removed. An upper-story window in the uphill gable end now opens into the barn.