Trethevy Farmhouse

Trethevy Farmhouse is a farmhouse of late 16th to early 17th-century date, substantially altered and enlarged in the late 19th century with some later modifications. The building is constructed of granite rubble with granite dressings, and has a bituminised slate roof with ridge tiles, including some hand-made crested ridge tiles, and gable ends. Two granite stacks with cornices and shaped tops sit at the right gable end and left axial position.

The original plan consists of a hall, cross passage, and lower end room, forming the remains of a formerly larger house. The rear wall of a former inner upper end room survives but the room itself is now contained within the 19th-century rebuilding. The lower end room to the right is heated by the gable end stack and features an unusually large pair of ovens to the left. A winder stair was probably inserted in the early 19th century at the rear of this room. The cross passage shows no evidence of a rear door; the building sits close into the bank at the rear. The rear of the passage was partitioned off in the later 17th or 18th century to form a small unheated dairy with a ventilator to the left of the door. The hall to the left is heated by the axial stack backing onto the passage and contains a stair tower of the original build to the rear, now blocked off and inaccessible. This stair tower is unusually wide and may contain a closet at ground floor level. Around the late 19th century, the upper end room was demolished except for its rear wall, and a large two-storey addition was constructed at the upper left end. This addition comprises a principal room projecting to the front in a gabled wing with a stack to the right side, a central stair hall, and a rear left wing of single-room plan with a rear stack. A stable was probably also attached to the front of the lower end room circa the same period.

The early building is of two storeys with the passage and lower end room at a lower roof level to the right, and presents an asymmetrical two-window front. The lower end has a door with a glazed panel and granite lintel, replacing the original ground floor window, and a small two-light casement at first floor. A rendered granite porch to the front of the passage features a pitched roof, and an inner four-centred arched granite doorway chamfered with step stops; the door is plain 19th-century with a re-used wooden-cased lock on the inside. Attached to the front of the lower end is a single-storey stable with loft and a doorway with timber lintel on the inner side; the front gable end has a window and ventilation slit above, with a single-storey lean-to at the outer side.

The hall displays paired 19th-century two-light casements to the front ground floor with granite lintels, and a first floor two-light casement with a raking dormer. At the rear, the lower end room has a two-light casement with granite lintel at ground floor. The rear of the passage has a ground floor three-pane light with a slate drip stone and no evidence of a rear door. The wall steps back to the upper end, with a wide stair tower featuring a pitched roof. This stair tower has a four-pane light at lower level, possibly lighting a closet under the stair, and a six-pane light to the side. The wall is continuous into the 19th-century addition to the right, incorporating the rear wall of the original upper end room into the 19th-century build.

The 19th-century addition is two storeys and pebbledashed. The front gabled wing has a square bay at ground floor with two-light casements, and two two-light casements at first floor; the right side of the wing has an external stack and two-light casements at ground and first floor. There is a gabled bay to the left of the wing with a three-light casement at ground floor and a two-light casement at first floor. The left side has a porch set in the angle to the rear room, which has two-light casements at ground and first floor and a stack to the left.

Internally, a chamfered wooden lintel spans the front door and the door to the left into the hall; the doorway into the hall is constructed in granite with a four-centred arch, chamfered with triangular stops, with pintles remaining from an early door. The fireplace to the axial stack is concealed, as is the entrance to the rear stair tower. Three very heavy cross beams with deep chamfer and bar and scroll stops span the hall; the central beam is supported on a granite pier of 19th-century date which forms the mullion for the front window. The rear of the passage is partitioned with a ventilator, forming a small dairy with a slate floor and slate shelves. Two steps lead down to the lower end room, which also has a slate floor and three very heavy roughly chamfered cross beams. The fireplace features a very heavy, slightly cambered granite lintel, with a late 19th-century oven inserted to the right and a pot jack remaining. To the left are two ovens, one larger (approximately one metre in diameter), both with domed interiors lined with granite and arched openings with stone rere-arches; a heavy granite lintel spans the access to the ovens. A 19th-century winder stair sits to the rear right.

The chamber over the lower end is ceiled and the roof is inaccessible. The roof over the hall consists of three bays; the principal rafters are not chamfered, lapped and pegged at the apices, with cambered collars notched and dovetailed and pegged. Trenched purlins and a diagonal ridge purlin, replaced in the 19th century, span across. A solid wall to the lower end, including the flue of the axial stack, is present. Although the upper end of this house has been lost, the plan of the original building remains clear and substantially intact; the roof over the lower end is probably also of the original build.

Trethevy Farmhouse is slightly earlier in date than nearby Trethevy Cottage, and the buildings share similar features. The concealed hall fireplace may be similar to the hall fireplace at Trethevy Cottage, if it remains in situ.