The 1842 Ordnance Survey six-inch map labels it simply as 'Bishop's Chapel (in ruins)', and ruin is very much what it has remained, though the quality of its stonework, chamfered quoins and dressed surrounds to the western door and windows, points to a building that was once taken seriously.

The chapel was consecrated in 1730, almost certainly serving the household at Bishopstown House as a private place of worship. By 1848, however, its datestones and memorials had been removed to St Finbarre's Cathedral in Cork city, a stripping-out that effectively erased its readable history in stone. The building is modest in scale, roughly nine metres east to west and five metres north to south internally, with a porch added to the west entrance in the same cut-stone manner as the original fabric. A doorway in the east wall is of particular interest: a covered walkway is said to have connected this entrance directly to the mansion house, creating a sheltered passage between the domestic and the devotional. Beneath the east gable there is a vault, and in 1865 the remains of two individuals, Peter Browne and Isaac Mann, were likewise transferred to the Cathedral, leaving the chapel emptied of both its monuments and its dead.