The building itself was demolished to ground level in 1976, leaving behind little above the surface, yet the dry summers that occasionally scorch Irish grass have quietly preserved the memory of its foundations in the soil beneath.

Oldbawn House was built in 1635 by William Bulkeley, Archdeacon of Dublin and son of Launcelot Bulkeley, Archbishop of Dublin, most likely on the site of an earlier structure. It was a substantial late Tudor H-plan house, meaning its footprint resembled the letter H when seen from above, with two projecting wings joined by a central block. That entrance front faced east, three bays wide, and was distinguished by a pedimented Gibbs porch, a classical doorway type framed by blocked surrounds, flanked by a pair of high-fronted gables. The longer north-west and south-east facades ran to six bays each, with massive decorated chimney stacks projecting forward from the walls. The house sat within a large defensive rectangular enclosure defined by a wide fosse, a defensive ditch, and the word "bawn", referring to such a fortified enclosure, is likely the origin of both the house's name and the townland itself. Symmetrical pleasure gardens lay to the south, including several fish ponds, among them one recorded as The Giant Fish Pond, set between a pair of orchards. The house was damaged during the 1641 rebellion and restored at the considerable cost of £3,000. Two of its interior fittings survived the eventual demolition: the original staircase and a stucco parlour mantelpiece dated 1635, decorated with a scene depicting the rebuilding of the walls of Jerusalem, the figures rendered in seventeenth-century dress, both now held in the National Museum of Ireland.

The site lies in the Oldbawn area of Tallaght in south County Dublin. There is nothing standing to see at ground level, and the parch marks that periodically reveal the house's outline are only legible from above, making archived satellite imagery the most rewarding way to appreciate the plan of what once stood here. Those wanting to handle something more tangible from the building should visit the National Museum of Ireland's collection, where the mantelpiece in particular offers an unexpectedly vivid connection to the Bulkeley household of 1635.