Built into the west gable, above what appears to have been a priest's residence occupying the western end of the building, is a fireplace and chimney. The joist holes for the timber floor that carried this upper storey are still visible in the north wall, and a blocked window behind the fireplace confirms that the hearth was added later, altering the roofline in the process. Below it, a narrow slit opening provided the only light to the ground floor of that domestic space. It is an unusual arrangement, the sacred and the functional sharing the same shell of coursed limestone.

The church is identified by the scholar Ó Cearbhaill, writing in 2007, as Cill Bhuí, the yellow church of Kilboy, a name now carried by the townland immediately to the south rather than by the building itself. The fabric is largely intact at the gable ends, and the east gable retains a single-light ogee-headed window, its external jamb stones finished with fine punch dressing within drafted margins, a detail suggesting craft and some local ambition. Against the interior face of the east gable there are traces of a large stone altar, now robbed out, measuring roughly 3.65 metres in length. The north wall preserves the lower jambs of the original doorway, which once had rebated double-chamfered stonework and a pintle hole, the socket for a door hinge. In 1840 the antiquarian John O'Donovan visited and recorded a carved Pietà lying on the ground outside the doorway, as well as the remains of a broken font. He also noted that burials had ceased there long before his visit. The carved stone depicting the Virgin and Child has since been moved, and now sits at the holy well in Kilboy, roughly 800 metres to the south-east. Earthwork traces in the surrounding ground suggest that the church once sat within a wider settlement, with possible house platforms and enclosures visible within 50 metres of the walls.