Trethevy

Trethevy is a farmhouse, now a house, of circa mid-16th century origin with substantial later developments. The building comprises a mid-17th century rear wing to the right, refronted in the mid-18th century, with further alterations made subsequently.

The structure is built of granite rubble, partly rendered, with a granite ashlar stack serving the rear wing. The roofs are of 20th century slate and asbestos slate with gable ends. Stacks are positioned at the gable end to the right, with rear lateral stacks to both the rear wing and the hall.

The building appears to have originally followed a two-room and through-passage plan, with the hall and kitchen to the right and an unheated dairy to the left. The rear passage door from this phase survives, though the front entrance has been replaced by a window. In the late 17th century, a parlour wing was built to the rear of the hall, enclosing the hall's rear lateral stack. This single-room wing was heated by its own external stack on the right-hand side and was later used as a granery at first-floor level. In the mid-18th century, a third room was added to the right-hand end and a new entrance passage was inserted at that end of the hall and kitchen, creating a nearly symmetrical front elevation. The original stair location is uncertain; a straight stair was inserted along the outer side of the rear wing in the 18th century. The 18th-century passage has a solid wall to the right (formerly an external wall) and a stud partition to the hall and kitchen, with ceiling beams in the hall and kitchen continuing over the passage.

The front elevation presents two storeys. The first floor has five 16-pane sash windows under the eaves, and the ground floor has four 12-pane sash windows with a central four-panelled door with overlight, creating a symmetrical composition. Ground-floor windows have chamfered granite lintels, except for one to the right; the window to the left was formerly a door. The dairy at the left end features a ventilation window.

The right gable end carries a stack with no corresponding stack evident at the left gable end, and more regular granite quoins to the right indicate later rebuilding of that end. The left end is rendered, with a single light at ground floor and a four-pane sash at first floor. The right gable end is of rubble; the rear of the right end is rendered with a single 20th-century light under the eaves.

The rear wing rises to two storeys, constructed in two phases with a slightly lower roof level where it joins the main range. On its right outer side is a nine-pane light at first floor, and a granite ashlar external stack with moulded string and cap, topped with a brick chimney. A single-storey rubble lean-to is set against the base of this stack, with a narrow stack to the hall. This lean-to has a splayed light at its outer end and a loading door to the side. The gable end wall of the wing is rendered. The left inner side of the wing has two 20th-century windows at ground floor and three at first floor, with a narrow single light having a splayed granite reveal at ground floor to the right.

The rear of the main range is served by a rear lateral stack in rough granite ashlar with moulded string and slate weatherings. A single-storey rubble lean-to runs along the rear of the hall and dairy, containing two 20th-century windows and a door, which conceals the original rear door to the hall.

Internally, the hall contains two large chamfered cross beams, one at the left end with mortices but insufficient space for a door, and seven beams with scratch-moulded decoration. The dairy is ceiled with a slate floor and shelves supported by a stone corbel on the front wall. Both front and rear windows to the dairy have deep splayed reveals.

The rear door to the hall, concealed by the rear lean-to, is constructed of granite with chamfering and a four-centred arch with pyramid stops. The hall fireplace is blocked, with an oven to the rear. The door to the passage is four-panelled; the passage itself has a granite floor. The end room to the right has a slate floor and a rough-hewn granite lintel to the fireplace at the gable end. The passage contains a moulded beam as in the hall.

The rear wing contains a straight stair against the right wall. The end room in the wing has a fireplace of circa 1800, constructed in granite with plain pilasters and a moulded mantel, and a four-panelled door. On the outer wall of the wing, the lean-to conceals a granary door and small single lights with timber lintels to the left and right.

The roof over the wing spans five bays with straight principals, halved and pegged, carrying cambered collars pegged to the faces of the principals, with two rows of purlins, some of later replacement. In the main range, a passage runs along the rear of the house, with three front rooms divided by plastered stud walls.

Trethevy was formerly part of the Pelyn estate.