How do I find old planning permission for my house in Ireland?

Local authorities are required under the Planning and Development Act 2000 to keep a permanent register of every planning application made in their functional area, including the outcome and any conditions attached. Most councils have digitised recent decades of records onto their online planning portal, where you can typically search by address, townland, or applicant name; for a private house, searching under the surname of the original owner alongside the address often works better than the address alone for very old records.

For applications made before online registers existed - commonly anything before the late 1990s or early 2000s, depending on the council - records may only exist in physical archive form. In these cases, contact the council's planning department directly, providing the address, folio number if known, and an approximate date range, and ask them to search the physical register or microfiche archive on your behalf; some councils charge a small administrative fee for this search.

If no planning application can be found at all, this does not necessarily mean the house or an extension to it is unauthorised - older houses may predate the planning system entirely (which began in its modern form in 1964), or the works may have qualified as exempted development at the time and therefore never required an application or generated a public record. A section 5 declaration from the council can help confirm the current planning status where genuine doubt remains.