what is exempt development?



Not all developments require planning permission. The variables that govern this include the planning history of the project, the location of the site and the particulars of the intended project. In fact, smaller residential extensions and conservatories to the rear of a property are often exempt if they meet the following criteria: 

  • The existing area of the floor of the house is increased by 40m2 or less. This figure includes any previous extension with or without planning permission. 

  • For terraced or semi-detached properties, any extension above ground level cannot be larger than 12m2 in floor area, including previous extensions. 

  • A space of at least 2m must be left from any boundary for extensions above ground floor level. 

  • The extension cannot surpass the height of the existing property.

  • The extension must leave a minimum of 25m2 of the existing private open space reserved for the occupants, to the rear of the property.

Height restrictions also apply to exempt developments, these are: 

  • Unless the rear wall of the property includes a gable, the extension height cannot surpass the height of the existing rear wall. 

  • If the rear wall of the property does include a gable, the extension wall’s height cannot surpass the height of the existing side wall. This rule does not apply to any gable built as part of the extension. A gable is characterised as the upper section of wall between ends of a sloping pitched roof. 

  • Flat roofed extensions cannot surpass the height of eaves or parapets of the existing property. Where no eaves or parapets are present, the extension roof cannot surpass the height of the existing property’s roof. 

Finally, there are restrictions to boundary distances and elements that may cause other properties to be overlooked. These are:

  • All windows at ground floor level of the property extension must be a minimum of 1m from the boundary that they face. 

  • All windows above the ground floor level of the property extension must be a minimum of 11m from the boundary that they face. 

  • Balconies and roof gardens are not permitted uses for the roof of the property extension. 


..still Not sure?

If you are unsure, your architect can help you.

Under Section 5 of the Planning and Development Act (2000), you can request a formal declaration from the planning authority to establish if you require planning permission for your particular extension proposal. To do so, you will need to complete a P07 Application Form for a Section Five ‘Declaration on Development and Exempted Development’. You should submit this form with a map showing the site location, any relevant drawings or photos, and the €80.00 application fee to the planning authority. If the planning authority does not require any further information, their decision will be issued to you four weeks after your request is received. Should you wish to appeal the decision, you may do so through the independent body An Bord Pleanála.


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