Twenty-two of them remain, distributed across the west gable, the east gable, and the south wall, each measuring roughly 23 by 20 centimetres and set about 1.2 metres apart. They run clean through the full thickness of the limestone rubble walls. One theory is that they served as putlog holes, the sockets used to anchor scaffolding during construction, but their regularity, their horizontal rows, and the fact that the building was a working barn point more persuasively toward ventilation. Keeping stored grain and hay dry in a damp Irish climate was a serious practical concern, and these apertures would have allowed air to circulate throughout.

The barn was not simply a farmer's outbuilding. According to the historian Carrigan, writing in 1905, it and its ancillary structures made up the monastic Grange of Hanumolt, a grange being an outlying farm estate managed on behalf of a monastery, used to supply the mother house with agricultural produce. The abbot responsible was from Graiguenamanagh, the Cistercian abbey on the River Barrow in south Kilkenny, and in 1540, at the suppression of the religious houses under Henry VIII, he was compelled to surrender it to the king's commissioners. By the time the first Ordnance Survey mapped the area in 1839, the site appeared as a small rectangular field simply annotated "Friars Barn". The 1947 revision shows a large roofless building, most of its north wall already gone, labelled as being in ruins. The ivy-clad west gable still stands close to its full original height, joist-holes near the top suggesting a loft once occupied that end of the building. Annamult Castle, a tower house, is visible about 100 metres to the north, a reminder that this quiet slope once held a cluster of interconnected medieval activity.