External wall insulation without planning permission
Insulation fixed to the outside walls of a house needs no planning permission if it is no thicker than 150 mm on the front, rear or gable walls, does not stick out onto a public road, and does not change the look of the house so much that it no longer fits the house and its neighbours. The exemption has applied since 27 July 2026.
The three conditions
Class 63 was added to the Planning and Development Regulations 2001 by S.I. No. 341 of 2026. It covers external wall insulation on a house and the works needed to fit it.
- Thickness. No more than 150 mm on the front, rear or gable walls.
- The road. The insulation cannot encroach on any public road.
- Appearance. The insulation and the related works must not materially affect the outside appearance of the building so that it becomes inconsistent with its own character and with the buildings next to it.
The third condition has no number. Citizens Information reads it as a finish that matches the rest of the building and the other buildings on the road.
The Department's circular presents the exemption as in line with existing SEAI grant provision.
Before you start
An exemption does not apply in some cases, for example if the work would break a condition of an earlier planning permission or extend an unauthorised structure (article 9 of the Planning and Development Regulations 2001). Houses that are protected structures or in an architectural conservation area have extra restrictions, according to Citizens Information. If you are unsure about the appearance condition, you can ask your council for a declaration under section 5 of the Planning and Development Act 2000 on whether the work is exempted development.
Insulation thicker than 150 mm, or that does not meet the other conditions, needs planning permission: see the fee for work to a house. Applications go to your council or through planning.localgov.ie.
Related rules: heat pumps, removing a chimney, and the drawing of the house.