It sits within the enclosure of Doonallia, a promontory fort, the kind of defensive structure formed by cutting off a headland from the mainland with a rampart, using the sea cliffs on the remaining sides as natural walls. That an entire cluster of domestic buildings should occupy the landward platform of such a fort is itself an oddity, suggesting long and layered use of this exposed Atlantic outcrop across different periods, though precisely when any of them were built or occupied remains unknown.

This particular house is the most northerly of three that crowd together at the higher, southern end of the fort's platform. It measures roughly 5.5 metres on its northeast to southwest axis and just under 5 metres on the other, making it a compact, near-square space. What survives is not walling in any conventional sense but a grassy scarp and bank, smothered in ferns through the summer months, that traces the outline of the structure and in places rises to 1.8 metres above the floor level on the interior. On the northern side the bank follows the cliff edge briefly, giving a sense of how close habitation pressed to the drop. There is a gap of about two metres in the bank between northeast and southeast, possibly the original entrance, with a small hummock sitting at its centre. The interior has a slightly dished quality, as though the ground has settled inward over time, and across its northern half runs a low, unexplained grassy ridge, roughly 2.4 metres long and only about 20 centimetres high, oriented east to west. What it represents, whether a partition, a raised sleeping area, or something else entirely, is not known.