The walls stand almost to their full original height, roughly 4.5 metres at the sides and 8 metres at the gables, and below the ground floor there is a vaulted chamber, its segmental arched entrance still visible just above the present ground level on the exterior. A drawing in the Memorials of Adare records a similar arch in the north wall, suggesting at least two points of access to this underground space. For a structure that receives relatively little attention compared to Adare's more celebrated ecclesiastical remains, the level of architectural detail preserved here is considerable.

The chapel is a small rectangular building, measuring 12.20 metres by 6.60 metres, and is situated approximately 20 metres north of St Nicholas's parish church. It is recorded in the Urban Archaeological Survey of County Limerick, compiled by Bradley and others in 1989, which describes the masonry as roughly coursed rubble limestone with dressed limestone quoins and jambs, the dressed stone being the more carefully cut pieces used at corners and around openings. The east wall retains a tall single-light cusped pointed window, its jambs chamfered and rebated, and the south wall carries a piscina near the east end, a shallow stone basin used for disposing of water that had been used in liturgical rites, indicating this was a functioning place of worship rather than a purely utilitarian structure. Internally, corbels and putlog holes above the western doorway indicate that a timber gallery once spanned the west end, supported by beams slotted into the walls at both sides. All four walls retain single-light cusped pointed windows, though the arch of the west window is no longer intact.

The chapel sits within the wider archaeological landscape of Adare village, close to St Nicholas's church, and is best approached on foot. The basal batter, a deliberate outward slope at the base of all four walls extending roughly 2 metres up from ground level, is worth looking for; it is a structural technique sometimes seen in medieval Irish buildings and gives the lower walls a slightly splayed profile. The carved detail around the doorway, particularly the chamfered soffit and pyramidal stops at the jambs, repays a closer look.