Treginnis Isaf/Lower Treginnis

Treginnis Isaf, also known as Lower Treginnis, is an early 19th-century farmhouse constructed from colourwashed rubble stone, featuring a grouted imitation slate roof and stone end stacks. To the right of the farmhouse is an attached service range, built in the mid-20th century, which has an even roofline, a slate roof, and a small end stack. The original house underwent restoration in 1989, during which 12-pane sash windows were renewed. The windows have cambered brick heads, slate sills, and nogged brick eaves. A rubble stone porch with a slate hipped roof was rebuilt in 1989, featuring a door with an overlight. There is also a lean-to on the west end of the house. The front garden is enclosed by rubble walls that rise to gatepiers and a pier at the southeast angle.

The service range was poorly rebuilt in the mid-20th century, with a new front wall and raised roof. It is finished in painted cement render and has metal-framed windows: two above, a door to the left below, a broad central window, and a window to the right. The east end has a whitewashed rubble lean-to.

At the rear of the main house, there is an outshut with a wall-face stack located to the left of center. The center features a 12-pane stair-light with a timber lintel under the eaves. There are small square lights with slate sills on the first floor, both left and right. The ground floor includes a 12-pane sash window to the left, a 6-pane casement to the right of center, and a small 4-pane window to the right. The rear of the service wing is cement rendered, with metal windows and one rendered stack on the roof slope.