The site consists of a central tower house surrounded by a substantial bawn, or defensive wall, complete with circular angle towers at the northeast and southwest corners. Historical records from the Civil Survey of 1654-6 describe it as ‘a good Castle with a slate house within a Bawne thereof alsoe an oarchard’, when it was under the proprietorship of Pierce Butler in 1640.

The bawn walls, constructed from limestone rubble in rough courses, form an impressive defensive enclosure measuring approximately 61 metres on the west side and 57 metres on the north. Standing at around 4.3 metres high with walls nearly a metre thick, this fortification retains much of its original character. The main entrance on the western wall preserves its original stone pillars, though the arch itself has been lost to time, whilst a blocked postern gate can still be seen towards the eastern end of the north wall. The defensive capabilities of the complex are evident in the numerous gun loops piercing the walls of both angle towers; the northeast tower alone features four at ground level, with additional defensive positions on its upper floor alongside a fireplace that would have provided some comfort to its defenders.

What makes Shanballyduff particularly intriguing are the architectural details that hint at daily life within its walls. Below the rounded stone coping of the north wall, six large square recesses with flat stone lintels suggest practical storage or perhaps defensive purposes, with similar features and corbels found elsewhere along the fortification. Though farm buildings have been constructed against the internal faces of the bawn over the centuries, and sections of the south wall have been incorporated into later agricultural structures, the site remains an evocative reminder of the fortified homesteads that once dotted the Irish countryside, where comfort and security went hand in hand during uncertain times.