Planning and Building Regulations are separate
Even where a project does not require planning permission, Building Regulations still apply. They cover structure, fire safety, ventilation, energy performance, drainage and more.
When may an attic conversion be exempted development?
Standard attic conversions inside the existing roof profile — for example, adding rooflights — may qualify as exempted development, subject to conditions and restrictions. Changes to the roof profile, dormers, or works to Protected Structures typically need a different assessment.
The 27 July 2026 update
From 27 July 2026, certain side and rear dormer developments may qualify for a new exemption. It is subject to an aggregate internal volume condition (30 m³), design requirements and other limits. Front dormers and works that go beyond the conditions typically remain subject to planning.
Protected Structures and ACAs
Additional controls apply for Protected Structures and Architectural Conservation Areas. Exemptions are usually more limited.
Section 5 declarations
A Section 5 declaration from the local authority is a formal confirmation of whether specific works are exempted development. It can be a useful step in unclear cases.
Useful references
- Department of Housing loft conversion guidance
- National Building Control Office FAQs
- Dublin City Council planning guidance
- Statutory Instrument 344 of 2026
What this means for your project
Every home is different. Use this guidance to ask the right questions and to shape your brief — but confirm what applies to your specific property with a home survey and appropriate professional input.
Start with a quick check of your attic.
Answer a few simple questions about your home and what you would like to create. We’ll give you an early indication of which conversion route may be worth exploring. A home survey is still required before suitability can be confirmed.
Or call +353 85 150 0853