To be logged as a monument without a century attached to it means the structure has resisted the usual methods of dating, whether through a lack of documentary sources, the absence of datable architectural features, or simply the erosion of whatever evidence once existed. It sits in the record as a fact without a story, which is often how the oldest or most altered buildings appear.

Drinagh is a small townland in Galway, a county where the layers of settlement run deep and where structures from very different periods can look surprisingly similar once time has done its work on them. A house of indeterminate date could be post-medieval, it could be earlier; the designation is an honest admission of uncertainty rather than an oversight. In Irish archaeology, domestic structures are among the most difficult to date precisely. Unlike churches or tower houses, ordinary houses were built and rebuilt using local materials and vernacular techniques that changed slowly and left few distinctive signatures. Without excavation or surviving written records, the best that can sometimes be said is that something was there, and that it mattered enough to record.