The wall may incorporate what was once the northern bawn wall of a much earlier castle, a bawn being the enclosed defensive courtyard that typically surrounded an Irish tower house. Reused architectural fragments are visible throughout: pieces with drafted margins and peck-tooling, chamfered edges, and one block with what appears to be a slight curve, all worked limestone salvaged from older structures and pressed into service when the garden wall was built or rebuilt.

The Civil Survey of 1654 to 1655 records the land here, then called Knockynanamy, as belonging to Piers Butler, described as an Irish papist, a formulaic designation used by the Cromwellian surveyors to identify Catholic landowners. On Butler's land at that time stood a castle, a little orchard, a few cabins, and a thatched house lately built by Thomas Batty and Henry Paris of Clonmel. That thatched structure has left no trace above ground, and neither has Knockeevan House itself, which appears on the first and second edition Ordnance Survey six-inch maps but has since been entirely demolished. What survives is a 30.6-metre length of earlier walling, standing to 2.3 metres, built of roughly coursed limestone rubble and terminating at each end with large limestone quoins, the squared corner stones that give a wall its structural integrity. Above those quoins, the wall was evidently modified at a later date, and it is in this rebuilt upper section that the reused carved fragments appear, keyed and patched into a wall that had already seen several lives.

The cut stone details, though modest in scale, are the kind that reward close inspection. Chamfered edges, where a right angle is cut away at 45 degrees to produce a bevelled face, and drafted margins, where a flat border is worked around a rougher central field, are characteristic of high-status medieval and early post-medieval construction. Seeing them embedded piecemeal into a garden wall speaks to a long habit of recycling dressed stone, common across Ireland wherever earlier buildings fell into decay or were cleared for new use.