The staircase is in the form of an open-well rising though four flights with four landings. The balustrades of the long flights are broken up by intermediate newel posts, a feature found in other Jacobean stairs such as Hanford House, Childe Okeford, in Dorset, built between 1604 and 1623. In addition the newel posts, handrail and string all have a small ovolo moulding to each corner and shallow “shadow moulding” in the centre, giving a richly moulded effect also seen at Hanford House. A 1937 house sale catalogue for Llwyn Ynn refers to “a really fine old oak carved staircase of exceptional width and easy tread”. This description fits the stair which is over five feet wide and has risers averaging only 6½ inches high; the catalogue also refers to the stair carpet which was 35 inches wide, exactly matching faint marks on the oak treads. The 1911 rcahmw volume on Denbighshire includes this description of the staircase at Llwyn Ynn: “…this doorway (the front door) opens into a large hall out of which leads a fine staircase, with flat pierced balusters, and tops and pendants to posts that are square in section…” a description which again favourably conforms to this stair.