Can a council make you demolish an unauthorised extension in Ireland?

Local authorities have statutory enforcement powers under the Planning and Development Act 2000 that allow them to require the removal, alteration, or demolition of unauthorised development, including extensions built without permission or built other than in accordance with a permission granted. This is usually done through an enforcement notice, which sets out the required steps and a timeframe for compliance.

In many cases, an enforcement notice will give the owner the option of applying for retention permission instead of immediately demolishing the extension, since the local authority's primary interest is usually in resolving the planning breach rather than automatically requiring demolition. If retention permission is refused, however, the authority can require the extension to be removed, and if the owner does not comply, it can apply to the courts for an order compelling demolition, with associated costs generally falling on the owner.

Whether demolition actually results depends heavily on the specific facts: an extension that could reasonably have been granted permission, or that meets exempted development limits with minor adjustment, is more likely to be resolved through retention or modification, while an extension that seriously breaches planning policy, overshadows neighbours, or was built in defiance of a refusal is at much higher risk of a demolition requirement.