The walls are standing, more or less, but so much has been rebuilt in concrete, re-pointed, and reconstructed over recent decades that what the eye takes in is a complicated layering of medieval stonework and modern intervention. The entire length of the south wall has been rebuilt on the footing of the original, the upper portion of the north wall is also recent, and the embrasure, head, and base of the east window have been remade in concrete. The result is a structure that is neither ruin nor restored building, but something in between, a condition that makes it more historically interesting, not less, once you know what to look for.

The church dates to the fifteenth or sixteenth century and served the parish of Iveruss, also recorded as Beagh. The name Iveruss is not, as the Ordnance Survey Letters of 1840 noted, of ecclesiastical origin at all; it was borrowed from the name of an ancient Irish tribe who were located in this area. By 1840, when the Ordnance Survey recorded the building in some detail, the south wall was still largely intact and retained a doorway with a two-centred pointed arch surround, missing its lower jamb stones, and framed outside by a shallow rectangular recess. The walls were still parapeted, standing around four metres high with the parapet adding between roughly half a metre and nearly a metre on top of that. The antiquary Thomas Westropp noted the site in 1904 to 1905. The rectangular structure, measuring just over nineteen metres east to west and nearly nine metres north to south, was built of uncoursed limestone in lime mortar, with large dressed limestone quoins at the corners and walls with a distinct outward lean at the base, a feature known as a batter, which helps distribute the load of a heavy stone wall.

The church sits in a graveyard that remains in use, located just south-west of the centre of the townland of Beagh. The one window that retains original medieval stonework is the central east window, which has a double ogee-headed light, meaning each of the two narrow lights is topped with a curved S-shaped profile, with recessed spandrels and a plain hood moulding above. A single ogee-headed light was also salvaged and incorporated into the rebuilt south wall. The base of a bellcote survives at the top of the west gable. Inside, the floor is covered with gravel, a recent grave plot occupies the north-west corner, and a newly built stone altar stands just north of centre. No patron day or saint has ever been recorded in association with this parish.