Cil y Groeslwyd-isaf

Cil y Groeslwyd-isaf is a three-unit, single-storey house with an attic, featuring a lobby entrance to the right of the center. The building is made of large blocks of random stone and has a slate roof with a tall stone ridge stack. Some timber-framing is visible on the east gable end, including a post to the right and a tie-beam truss with a cambered tie-beam, collar, and two vertical struts. There is evidence of an addition on the west bay, where the masonry has been partially rebuilt. The entrance is offset to the right of center and is flanked by windows, which have segmental stone voussoirs above them. There is an additional window in the left bay that lacks a lintel. The entrance features a late 20th-century half-glazed panelled door, and the windows have been replaced with late 20th-century two-light wooden windows. A gabled attic dormer with a similar window is located to the left of center. The west gable end is rendered and built into the bank, with a wooden balcony leading to a gable door and a window to the right. The east gable end is made of masonry below the tie-beam, with a doorway on the far right that has been infilled with stone, and a two-light window to the left; the timber-framed gable has a single light window between the struts. At the rear, towards the east, there is a rendered lean-to with a prominent stone plinth, which includes a two-light window at the east end and a skylight on the rear roof pitch. A late 20th-century wing is attached to the rear of the lean-to, featuring a garage and carport on the east front, with three gabled attic dormers above.

Inside, the lobby entrance leads to two heated rooms: a hall to the left and a parlour or service room to the right. Both rooms have back-to-back fireplaces with chamfered timber lintels. The ceilings feature medium-chamfered spine beams and chamfered joists, which are well-preserved in the right room but slightly altered in the left room. The west bay, added later, has a stop-chamfered beam that appears to have been reset. Between this bay and the hall, there is a timber-framed partition with open panels, which formed the original west gable end of the house.