# Do I need planning permission for air conditioning in the UK?

*The Datum team · Heating, cooling & plumbing engineers · Datum · updated 2026-10-19 · Air con*

Usually no, if the system provides heating as well as cooling: the Planning Portal says air conditioning may then be permitted development, within limits on size, siting and number of units. Cooling-only units need planning permission, and listed buildings and conservation areas need consent. Flats may also need freeholder consent under the lease. We check all of this at the survey.

## Does a house need planning permission for an air-conditioning unit?

Usually not, provided the system also heats: the Planning Portal says a cooling-only unit needs planning permission. For a typical house, one sensibly sited outdoor unit may then fall within permitted development, provided the limits and conditions are met, and the installation must comply with building regulations.

## Do flats need permission for an outdoor unit?

In practice, yes: ask first, always. Your lease will usually say whether you need freeholder or management-company consent for an outdoor unit, separate from planning. Getting that in writing first avoids expensive arguments later, and we can supply the spec sheet and noise data that makes the request easy.

## How long does a planning application take?

If your unit does need planning permission, GOV.UK says most planning applications are decided within 8 weeks, and in England the limit is 13 weeks for unusually large or complex applications. Your local authority can ask you to agree an extension if it needs more information.

## What about listed buildings and conservation areas?

Listed buildings need listed building consent for external plant, full stop. In a conservation area the Planning Portal says permission will be required. Neither is necessarily a no: it is a case of routing it properly, and we have done both. We confirm which rules apply at the survey, before you commit to anything.

> For most houses the planning answer is yes-you-can. The expensive mistakes are flats without freeholder consent and listed buildings — ask before the bracket goes on the wall.
>
> — The Datum team, Heating, cooling & plumbing engineers

## Related questions

### Will the outdoor unit annoy my neighbours?

Manufacturers publish sound data for both the indoor and outdoor units, and siting is half the job. We position for airflow, serviceability and neighbour relations, and can share the noise figures for the unit we propose.

### Who checks whether my install is compliant?

We do, at the survey — permitted development conditions, lease position if you're in a flat, and conservation/listed status. It's part of the fixed quote, not an extra.

### What if I already had a unit fitted without consent?

It depends on which consent is missing. Retrospective applications are often possible — get the paperwork straight before selling the property, when it always surfaces.

## Sources & verification

- [Planning Portal — Do I need planning permission to add air conditioning? (may be permitted development only if the system provides heating; cooling-only needs planning permission; once a planning application is validated "the formal decision period is 8 weeks", which the local authority may ask to extend for complex proposals or if more information is needed; conservation area permission required; listed building consent required; accessed 19 Oct 2026)](https://interactive.planningportal.co.uk/faqs/do-i-need-planning-permission-to-add-air-conditioning-to-my-home)
- [MHCLG — Air conditioning rules (generally no planning permission for a small home if it would not materially affect the outside appearance; check with your council; 25 Jun 2026; accessed 19 Oct 2026)](https://mhclgmedia.blog.gov.uk/2026/06/25/air-conditioning-rules/)

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Canonical page: https://www.datumclimate.co.uk/guides/planning-permission-air-conditioning