Plas rhiw-saeson

Plas Rhiw-Saeson is a building constructed from coursed local rubble stone, topped with slate roofs, and featuring slate hung to the rear. The main range of the building is three storeys high and consists of three bays. It has a late 19th-century four-panelled door with an overlight, set beneath a small cantilevered gabled canopy. The windows are 19th-century timber designs with six panes and a central iron casement on a quadrant stay, and there are gable stacks present.

The forward wing, which may be older, has two bays and features a gable with a five-light window that replaces an ovolo moulded window mentioned by Haslam. There is a door to the front bay on the side, accompanied by an open timber porch. A cellar is located under the central bay. Attached to the side of the wing are two contiguous gabled service wings, with the front wing displaying a semi-circular headed date stone that reads "ATHELSTAIN / OWEN:ESQR / WALL'D:THIS / HOVSE:ROUND / IN THE:YEAR / 1719." The first letter and last digit are unclear. The upper rear portion of this addition was likely used as a seed grain store.

At the time of inspection in August 1996, the interior was not accessible. It is reported that the main front door opens into a later stair. To the left in the main range, there is a parlour at the south end, which was later used as a kitchen and features bracket moulded cross ceiling beams. The current kitchen in the forward wing has an ornate moulded ceiling and enriched faces on the posts. A post and panel partition with incised mouldings marks the junction of the two ranges, with an original doorway present. The ceiling above the main chamber has counterchanged joists, and the roof is plain with windbraces supporting the trusses over the main range.