Porthmissen Farmhouse and Garden Walls to Front

Porthmissen Farmhouse and the garden walls to the front were likely built in the 18th century and extended in the early 19th century. The farmhouse is constructed of stone rubble, with slate hung on the front and side elevations, featuring rag slates. It has a steeply pitched slate roof with gable ends on the front range and a double gable end at the rear, along with brick end stacks.

The original plan of the farmhouse is uncertain, but the current layout is a double depth plan with a central entrance. The two main rooms at the front are heated by end stacks, with a staircase located at the rear of the passage. The kitchen is situated in a wing at the rear left, also heated by an end stack, while a parallel wing to the rear right contains the dairy. A straight joint on the rear and right-hand side elevations suggests that the right-hand wing, which housed the dairy, is likely an early 19th-century extension.

The exterior features two storeys and an attic, with a symmetrical three-window front. There is a central 19th-century gabled stone rubble porch flanked by two six-pane horned sash windows, and three additional six-pane horned sash windows on the first floor. The rear elevation remains unaltered, showcasing a stair window near the center and a line of pigeon holes above the dairy on the left.

The garden wall in front of the house, dating from around the 19th century, is made of stone rubble and includes gate piers. It encloses the garden and rises to the right and left, screening the farmyard to the right.