There are only two instances when you might require planning permission to get insulation installed in your home: if it will change the external appearance of the building or if it will affect the fabric of certain protected buildings.

Of the different ways to insulate your home, external wall insulation is most likely to need planning approval.

External insulation typically consists of a layer of insulation affixed to the wall, which is then covered by a basecoat, a reinforcing mesh, and a render applied over the top to protect it from the elements.

This is most commonly used in homes which are not suitable for cavity wall insulation, or where internal insulation would reduce your floor space too much.

Whether planning approval will be needed for external insulation will depend on where your home is located, whether it is in any way protected, and how the end appearance compares with the original look of the building and any nearby buildings.

Work which have the potential to alter the external appearance of a building, especially if it is in an urban setting, may require you to seek planning permission. 

This is because local councils typically do not want individual houses within a street to have a drastically different material character from their neighbours.

So things such as attic, cavity wall, or internal insulation are likely to be fine. On the other hand, external insulation applied to the outside walls of a building could be considered a development requiring approval.

For instance, if you were to apply external insulation with a render to a brick wall house, on a street with other brick homes, this would be something which would require planning approval.

Examples such as I have given above might be refused approval depending on the location, but if the potential change in appearance is not great and would not alter the character of the area, then there is a good chance it will be approved.

Specifically, external insulation might be exempt from planning requirements if it falls under Section 4(1) (h) of the Planning and Development Act 2000.

That is works for the maintenance, improvement or alteration of a building:

“which affect only the interior of the structure or which do not materially affect the external appearance of the structure so as to render the appearance inconsistent with the character of the structure or of neighbouring structures;”

Restrictions on works on the outside of a building, such as external insulation, will be stronger in the case of Protected Structures or any building inside an Architectural Conservation Area.

There are more stringent planning requirements for any works Section 57 (1) (a) & (b) of the planning acto goes on to state that work on a protected structure shall only be exempt as long as it doesn’t: 

“Materially affect the character of the structure or any element of the structure which contributes to its special architectural, historical, archaeological, artistic, cultural, scientific, social or technical interest”.

This could apply to external insulation, but also to internal works such as internal wall, attic, or cavity wall insulation if the works would affect any element of the building which is considered part of what makes it special.

Similarly, any works on the outside of a building which is located in an Architectural Conservation Area is only exempt from planning requirements as long as it “would not materially affect the character of the area” in the ACA.

If you get insulation installed believing it to be exempt, which it later turns out did require planning, then it may be possible to get retention permission.

Retention planning is an application for planning permission for an alteration or development which was made without planning approval.

Getting retention permission comes with a planning fee three times higher than the regular fee, and is by no means guaranteed if the council deems the work unacceptable.

However, if approved, it can avoid the potential for enforcement notices or legal proceedings that can come from an illegal development.

If you’re interested in getting insulation installed in your home then get a free consultation today with one of Ireland’s top rated installers.

The contents of this article are for informational purposes only and should not be considered in any way as legal advice.