Plas Trefaldwyn

Plas Trefaldwyn is a house of two and a half storeys with cellar, built in red brick laid in Flemish bond with deep-eaved slate roofs. The building displays a mix of 18th-century origins with substantial 19th and early 20th-century additions and alterations.

The north entrance front comprises three bays with an open pedimental gable to the centre bay, which contains an attic window. The gable is flanked by twin square brick stacks joined by a brick arch with stone sill, with stone plain cornice across both stacks and four octagonal yellow chimney pots to each. The brickwork of the right bay and gable differs from the rest of the front. Windows on the main floors are 12-pane sash windows with cambered heads of gauged brick and stone sills—three above and one to the ground floor left, with two to the right. The attic has a replaced 9-pane window with hopper opening top.

The entrance is marked by a handsome neo-Grec central sandstone ashlar porch with two baseless columns in antis, plain frieze, cornice and blocking course. The paired column and pier each side, with a taller shallow-gabled centrepiece, frame a doorway within a shouldered timber architrave containing a 5-panel door with two glazed panels. Steps descend to the left-hand cellar door. A small chimney and single-storey red brick extension with two matching sash windows and monopitch roof occupy the right end.

The east garden front is three bays, two storeys and attic, with open pedimental gables to each bay, the centre bay projecting. A brick chimney sits in the valley to the left of the centre gable. Twelve-pane hornless sash windows appear in the outer bays on main floors and nine-pane sashes to the top floor, with gauged brick heads. The centre bay features similar attic and first and ground floor French windows linked vertically under a single cambered broad head. These French windows are tripartite with long 5-pane sidelights and marginal glazing bars to centre opening doors, divided by very thin pilasters with entablature. A wrought iron balcony with scrollwork pattern adorns the first floor, beneath which is a painted panel between floors divided into three by miniature pilasters. The brickwork of the centre and the gables each side differs from the rest; straight joints on the sides of the centre projection reveal that the 18th-century house originally had a slight projection to the centre bay.

The lesser south elevation has an open pedimental gable flattened at the apex, with garden-wall bond brickwork. A 12-pane hornless sash with gauged brick head lights the attic, whilst a horned 12-pane sash occupies the first floor left and a 20th-century glazed door the first floor right, opening onto a flat roof of the ground floor extension. This extension features a castellated parapet and three large cambered-headed 12-pane sashes. A French window on the east side opens into a conservatory in the angle to the garden front.

The rear elevation contains a gable to the left wing, which is the end of an earlier 19th-century addition to the north front, with an open pedimental gable. This gable has a 20-pane attic window and 16-pane first floor window, both with cambered heads. The main rear wall, of old brick in garden-wall bond, has a centre first floor 12-pane sash, an eaves-breaking window to the left of centre, and a fire-escape door to the right. An added 19th-century lean-to with a small-paned iron 3-light window with top lights extends across the rear and continues around the south side of the wing. To the right is a broad added gable, probably early 20th-century, in stretcher bond brickwork. The north side has one iron cross-window, whilst horned sashes on the west wall sit above a lean-to with iron small-paned windows.

The building has not been fully inspected. Window shutters and shutters to the front door are present, along with six-panel doors. The interior features an arch in the hall and a staircase with straight balusters and bracketed tread ends.