Plas Llanarmon

Plas Llanarmon is a house constructed of rubble stone with slate roofs, featuring a short main range and crosswings of unequal size. The smaller wing on the right serves as a storeyed porch. It has a stone side wall stack on the main south crosswing and a large stone square stack towards the north end of the ridge, where it meets the roof of the smaller northeast crosswing. The building has two storeys and an attic.

The east front showcases a broad gabled crosswing on the left and a narrower gable projecting to the right. The left crosswing gable features 19th-century timber bargeboards and 20th-century windows that likely replaced late 19th-century sashes. The attic has a pair of casement windows, while the first floor has two 6-pane hardwood windows, with the larger ground floor window also featuring renewed red brick cambered heads. The south side of the crosswing includes an external chimney breast on the right, followed by a large 20th-century stair-light with a brick head, and one window on each floor to the left.

The recessed center of the east front has a large 20th-century hardwood casement pair on the first floor under the eaves, with a similar large window below. The projecting right gable has moulded stone coping with kneelers, and there are large 20th-century 4-pane sashes on the first floor, a small 20th-century 4-pane sash on the ground floor to the left, and a part-glazed door to the right, which features stone voussoirs to its cambered head. The north side is windowless and continues with the north end of the main range, which has 19th-century overhanging eaves and a 20th-century casement pair on the first floor. The ridge line of this gable back to the chimney is slightly lower than the ridge south of the chimney.

Inside the south crosswing, there is said to be an important 17th-century decorated plaster ceiling featuring panels with vine trail and floral trail motifs, including a human figure with flowers at the center. There is also one plastered beam. To the west in the crosswing is a stair hall with an oak dog-leg stair, which has turned balusters and square newels. The central room contains a heavy beam and a deep fireplace to the right.