The name appears on the Ordnance Survey six-inch map of the area around Loughill in County Kilkenny, annotating a ruined church on a west-facing slope above marshy ground, yet the OS Letters of 1839 make no mention of the dedication at all. The historian Carrigan, writing in 1905, noted that Bishop Phelan's List of Ossory Patrons actually assigns the church to the apostles Simon and Jude, the latter also known as Thaddeus, and Carrigan admitted he could not establish where the Chadden association had come from. The name has simply stuck, floating free of any traceable origin.

The church itself is a single undivided rectangle, just under sixteen metres long and six and a half wide, built from roughly coursed limestone and shale rubble set in a lime mortar with a notably high pebble content. The east gable still stands to around five and a third metres, and its most striking feature is a tall lancet window, three and a third metres high, with voussoirs, the wedge-shaped stones that lock an arch in place, framing a wide, shallow embrasure. The cut stonework of the sill and dressings has been removed entirely, as is common in ruins that were quarried by later generations, but the voussoirs remain and, along with the overall form, point clearly to a thirteenth-century date. Much of the north wall survives to a height of about three and a half metres, though the western lengths of both the north and south walls have begun to lean outward, and rubble from the long-collapsed west gable spreads across the interior and out beyond its former line. The quoins at the corners are well preserved, though they are made from quite thin slabs rather than the substantial dressed blocks one might expect. An associated graveyard lies nearby.

The site sits on a natural terrace, and the ground drops away sharply to the west of where the west gable once stood, leaving the ruin with open views to the west, north, and south, the slope rising and closing things off only to the east. The terrain approaching the church is wet and marshy, so the going underfoot can be soft, and the leaning walls on the western end of the structure are a reminder that what remains is continuing to move.