Retention planning permission in Ireland — refused 27% of the time, against 7% for extensions

Retention applications were 17% of everything the seven Greater Dublin Area councils we index received in the 12 months to 12 September 2026: 1,996 of 11,409. Of those decided, 81% were granted. The comparison is the point. Over 24 months, 27% of retention decisions were refusals against 7% for extensions applied for in advance. Fingal refused 73 of the 202 retention applications it decided, 36%. Retention is planning permission for something already built: an extension that outgrew the exemption, a garage that became a flat, a use that started without permission. The Planning and Development Act 2000 treats it as an ordinary s.34 application with the same notices, the same five-week window and the same eight-week decision. The fee is treble, and the odds are worse.

When retention is needed

Development carried out without a permission that was required, or in breach of a condition, is unauthorised development. There are three ways it ends: retention permission, enforcement, or the passage of time. Retention is the only one you control.

The Dublin registers show the same cases again and again. An extension that exceeded the exempt limits, counting an earlier one, or that went to the side of the house. A garden building that became a dwelling. A change of use: a house to two units, a shop to a takeaway, a dwelling to short-term letting. A dormer, a front porch beyond 2 m², a boundary wall over 2 m. Works built under a permission but not as drawn.

What retention cannot do

Section 34(12) of the 2000 Act was inserted in 2010 after the Court of Justice of the European Union ruled against Ireland. It bars a council from considering retention where the development would have needed an environmental impact assessment, a screening for one, or an appropriate assessment under the Habitats Directive. For a house extension this is rarely engaged. For a quarry, a large agricultural building or anything near a Natura 2000 site it can close the door, and the only routes left are substitute consent under Part XA or removal.

Retention does not cure a breach of the Building Regulations. It does not bind a neighbour with a private-law remedy over light or a boundary. And it does not stop enforcement already under way for the period before the grant.

The application and the fee

You lodge a retention application like any other: newspaper notice and site notice within the two weeks before lodging, both carrying the word "retention"; drawings of the works as built; the fee. Neighbours have five weeks from the council's receipt date to observe for €20, and four weeks after the decision to appeal to An Coimisiún Pleanála (formerly An Bord Pleanála). The council decides within eight weeks, or four weeks after any further information (FI).

Schedule 9 of the 2001 Regulations sets the retention fee at three times the fee for the same works applied for in advance, capped at €125,000. For a domestic extension that is €102 instead of €34. For a commercial change of use it runs to thousands. The fees guide has the schedule.

The planner assesses the works as if they did not yet exist. That they are built is not a reason to grant. Where the works are broadly acceptable but something is wrong, a window overlooking a neighbour or a flat roof higher than drawn, the grant may carry a condition requiring alteration.

How often retention is refused

Part of the gap is selection. The work that ends up in a retention application is the work an architect would have talked you out of. Part is that a planner cannot condition a built structure into acceptability the way a drawing can be revised.

Applying and failing is worse than not applying

We read the retention refusals on the Dublin registers from the spring and summer of 2026. Dún Laoghaire-Rathdown refused retention of a rear extension at 50 Richmond Park, Monkstown on 20 August 2026. Dublin City refused retention of a kitchen and a garage converted to 32 m² of habitable space at 12 Windmill Road, Crumlin, on 26 March 2026 (WEB1196/26). The owner came back with the same works. The council refused again on 30 June 2026 (WEB2098/26). Both refusals are now on the register against that address for good.

Our reading: apply for retention before you list the house, not after the buyer's solicitor asks, and only after an architect has told you it will pass. A refused retention application is a permanent entry that every future search will find. If the advice is that the works will not pass, the seven-year rule and a price adjustment may serve you better than a second refusal.

If you do nothing: enforcement and the seven-year rule

Anyone can write to a council about unauthorised development. The council investigates and can issue a warning letter under s.152, then an enforcement notice under s.154 requiring the works to be removed or altered. After that comes prosecution, or an application to the Circuit or High Court under s.160. The Office of the Planning Regulator counted 7,396 new enforcement cases nationally in 2024.

Section 157(4) stops a council issuing a warning letter or enforcement notice, or bringing proceedings, more than seven years after the unauthorised development began. There are exceptions for protected structures, quarries and conditions about use. The seven years limits enforcement; it does not grant permission. The development stays unauthorised, and that bites when you sell.

Selling a house with unauthorised works

A purchaser's solicitor will ask for evidence that every alteration since 1 October 1964 was exempt or permitted. For works that were neither, you have a retention application before sale (three to five months, with the risk above), an architect's opinion that enforcement is statute-barred under s.157 with a price adjustment, or, for older and minor works, an indemnity. The Law Society's practice note on planning searches sets out what the buyer's side must check.

Check the register for the address

Search the Explorer or Find for any address to see retention applications and their decisions on the street. The Fingal place page shows that council's live retention share and grant rate; the Blackrock page does the same for the electoral area.

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

What is retention permission?

Planning permission applied for after the development has been carried out. It is decided under s.34 of the 2000 Act like any other application, at three times the fee.

How much does retention planning permission cost in Ireland?

Three times the fee for the same works applied for in advance (Schedule 9 of the 2001 Regulations): €102 for a domestic extension, capped at €125,000 for large developments. Notices, drawings and consultants are extra.

Is retention permission usually granted?

Less often than a normal application. In the Dublin registers about four in five retention applications that reach a decision are granted, against more than nine in ten extension applications made in advance.

After seven years is an unauthorised extension legal?

No. After seven years the council generally cannot take enforcement action (s.157(4)), but the extension remains unauthorised development. That affects a sale and any future application for the property.

Can a neighbour object to a retention application?

Yes, in the same way as to any application: an observation to the council within five weeks of receipt for €20, and an appeal to An Coimisiún Pleanála within four weeks of the decision.