How long does planning permission last? Five years, and a 79% rate on extensions of duration

The seven Greater Dublin Area councils we index received 343 applications to extend the duration of a permission in the 24 months to 12 September 2026. Of the 305 decided, 242 were granted and 63 refused: 79%. Section 40 of the Planning and Development Act 2000 gives a permission five years from the date of the grant, unless the grant itself sets a longer period under s.41. After that, any part of the development not carried out is unauthorised. The extension procedure in s.42 is the one chance to add time. Its two tests are settled before you ever lodge the form: did you apply before expiry, and had you done substantial works by then.

Five years from the grant, not the decision

The five years run from the date of the final grant. That is the document issued after the four-week appeal period, or the decision of An Coimisiún Pleanála (formerly An Bord Pleanála) if the application was appealed. It is not the council's decision to grant. A permission granted on 3 March 2022 expires on 3 March 2027. The date is on the permission and on the council's register.

Councils can set a longer period under s.41 where the scale of the development warrants it. Large phased schemes commonly get seven or ten years. Check the grant.

What expiry means

Development carried out after the permission expires is unauthorised, as if there had been no permission. Works completed within the period remain lawful. A house half-built when the permission lapses is, for the unbuilt half, unauthorised development. Your options are a new application, retention for what has been done, or an extension of duration if you sought one in time.

Expiry matters for buyers too. A site sold "with planning permission" is worth what the remaining period is worth. A permission with eight months to run and no works begun may not be capable of extension at all.

Extending the duration under s.42

Section 42 lets the holder of a permission apply to the council to extend the appropriate period. The application must be made before the permission expires; one lodged the day after is refused as a matter of law. The council must be satisfied that the development was commenced before expiry, that substantial works were carried out in that period, and that the development will be completed within a reasonable time. If those tests are met the council must grant the extension, for the period it considers necessary up to five further years. A permission can be extended once.

Articles 40 to 47 of the 2001 Regulations set out the application: a form, a fee, particulars of the works done and their dates. There are no public notices and no observation window for neighbours. The Aarhus Convention Compliance Committee criticised that in 2019, after a Meath quarry's permission was extended three times with no opportunity for the public to take part. The Planning and Development Act 2024 restates the duration and extension provisions and changes the rules when those sections are commenced. Check the commencement orders on irishstatutebook.ie for the position on the day you apply; until then s.42 of the 2000 Act applies.

The council has eight weeks to decide. There is no appeal to the Commission against a refusal to extend. The remedy is judicial review, or a fresh application.

What "substantial works" means

The Act does not define it and the cases turn on their facts. Clearing a site, fencing it and digging a trial hole have been held not to be substantial. Foundations and rising walls for a meaningful part of the scheme have. For a house, the line usually sits around foundations poured and the structure begun.

Commencement: the notice that proves you started

The planning permission is one thing; the Building Regulations are another. Before starting most works you must lodge a Commencement Notice on the Building Control Management System (BCMS) not less than 14 and not more than 28 days before the works begin. The notice is public, which is why we can count them. Its date is the first thing a council, a solicitor or a purchaser looks at when the question is whether a permission was acted on in time. Starting without one is an offence under the Building Control Act 1990, and it leaves you without the record a s.42 application needs.

The Department of Housing publishes national monthly counts. Its December 2025 release reported 16,412 notices for 2025 against 69,311 in 2024, the earlier year inflated by a rush to start before a development-levy waiver ended.

How often extensions of duration are granted

Refusals are mostly for the two statutory reasons: the application came after expiry, or the works done were not substantial. Neither is a matter of planning merit.

The councils are not equally strict. In the same 24 months Dún Laoghaire-Rathdown refused 15 of the 37 extension applications it decided, 41%, while Meath refused 23 of 163, 14%. Fingal and Dublin City do not label extension-of-duration applications as a type in the feeds we hold, so they are missing from the count. A refused s.42 application sits on the register, 25 Balally Grove, Dundrum being one from 9 April 2026, and the permission expires anyway.

Our reading: decide in year four. If the foundations will not be in by month 54, either get them in or plan a fresh application while the old permission is still a live precedent. Do not spend the last month on a s.42 form.

Check a permission's dates

Every application in the Explorer shows its grant date and any commencement notice we have matched to it; the map's commencements layer shows where permissions are being acted on. The South Dublin County Council place page and the Tallaght Central page carry live commencement counts.

Figures from the register on 12 September 2026 (live callouts refresh hourly); law checked 12 September 2026. Check with the council or a planning consultant before relying on this.

Frequently asked questions

How long does planning permission last in Ireland?

Five years from the date of the grant (s.40 of the 2000 Act), unless the permission specifies a longer period under s.41.

Can I extend my planning permission?

Yes, once, under s.42, if you apply before it expires, the development has commenced, substantial works have been carried out and it will be completed within a reasonable time. The extension can be up to five further years.

What happens if planning permission expires before the house is finished?

The unfinished part becomes unauthorised development. You would need a new permission, or retention for works done, unless an extension of duration was granted before expiry.

Does clearing the site count as commencement?

Usually not as "substantial works" for s.42. Foundations and structural works are the kind of evidence councils and courts have accepted. Lodge a Commencement Notice on BCMS before starting so the date is on record.

Can neighbours object to an extension of duration?

Under the 2000 Act there is no public notice or observation window for a s.42 application. The 2024 Act changes the duration provisions when commenced; check the current position with the council.