Do air conditioning units need planning permission?

It depends on the type of unit and the building. A reversible heat pump can be permitted development under Class G if every condition is met, while a cooling-only unit cannot use that route and may need an application. Conservation areas, flats and listed buildings add further checks.

Do I need planning permission to install air conditioning on my house?

Usually not for one air-to-air heat pump on a house in England, provided every Class G condition is met: outdoor unit no more than 1.5 m³, MCS 020a noise compliance, and not above ground floor on a street-facing wall. A detached house can have up to two units under this route.

Can I install air conditioning in a conservation area?

Yes, but not on a wall or roof that fronts a highway without planning permission. Rear or concealed positions can still be permitted development if every Class G condition is met. Check for any Article 4 direction covering your street.

Do my neighbours have to agree to air conditioning?

No. Permitted development does not require neighbour consent, but the installation must meet the MCS 020a noise limits. If you need a full planning application, the council will publicise it and neighbours can comment.

Is planning different in Wales and Scotland?

Yes. The Class G rules described here apply in England. Wales and Scotland set their own permitted-development rules for heat pumps, so check with your local council. The £2,500 grant covers England and Wales only.

Planning · England

Do I need planning permission for air conditioning in England?

Q: Do you need planning permission for air conditioning in the UK?

In England, an air-to-air heat pump that heats as well as cools can usually be installed on a house without a planning application, if every Class G limit and condition is met. Cooling-only units cannot use that route. Wales, Scotland and Northern Ireland have their own rules.

Q: Do I need planning permission for air conditioning in a flat?

A block of flats can use Class G if every condition is met, including a 0.6 m³ limit on the outdoor unit and only the first unit on the block. You will also normally need written consent from your freeholder or managing agent under the lease.

Q: Do I need planning permission for air conditioning on a listed building?

Listed buildings have no Class G permitted-development rights. Listed building consent is always required, whichever wall the unit sits on, and planning permission may also be needed.

Last updated 27 September 20268 min read

The short answer

A house in England: usually no planning application is needed for one air-to-air heat pump that heats as well as cools, provided every Class G limit and condition is met.

Cooling-only air conditioning: the Class G heat-pump route does not apply, so check with your local council before you install.

A flat, conservation area or listed building: expect more checks. Flats need lease and freeholder consent as well as the Class G conditions; conservation areas rule out walls and roofs fronting a highway; listed buildings always need listed building consent.

See if the £2,500 grant applies to your home first. Five questions.

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Heat pump vs cooling-only air con: why it changes the answer

Most modern wall-mounted air conditioners are reversible: they can heat a room in winter as well as cool it in summer. A reversible unit that heats is an air-to-air heat pump, and in England it can use the Class G permitted-development route for air source heat pumps, if every limit and condition is met.

A cooling-only unit is not a heat pump for these purposes. It cannot use Class G, and it does not qualify for the £2,500 Boiler Upgrade Scheme grant either. Whether it needs a planning application depends on the building and the location, so the council is the place to ask.

The practical upshot: if you are choosing a system, a heat pump that heats as well as cools is usually both easier to get through planning and the only type the grant can cover.

The Class G conditions

These are the main limits and conditions for an air source heat pump under Class G of Part 14 of the General Permitted Development Order, as amended on 29 May 2025. If any one is not met, you need a planning application.

Condition	House	Block of flats
Outdoor unit volume	No more than 1.5 m³	No more than 0.6 m³
Number of units	First unit on a non-detached house; first two on a detached house	First unit on the block
Noise	Must comply with MCS 020a	Must comply with MCS 020a
Street-facing walls	Not above ground floor on a wall facing a highway	Not above ground floor on a wall facing a highway
Conservation areas	Not on a wall or roof fronting a highway	Not on a wall or roof fronting a highway
Listed buildings and scheduled monuments	No permitted-development rights	No permitted-development rights
Wales	Separate rules apply, check locally	Separate rules apply, check locally

Summary of GPDO Schedule 2, Part 14, Class G and GOV.UK / Planning Portal guidance as amended 29 May 2025. The legislation is the authority; your installer or council can confirm how it applies to your address.

Houses

On a house, the outdoor unit usually goes on a rear wall, in a side return, or on a stand in the garden. These spots tend to meet the street-facing and noise conditions most easily, and keep pipe runs short.

If you want certainty, for example before selling or if a neighbour is likely to object, you can apply to the council for a lawful development certificate. It confirms the installation is permitted development without a full planning application.

Flats and leaseholds

Class G can apply to a block of flats if every national limit and condition is met, but each proposal needs a site-specific planning check. The unit limit applies to the block as a whole, so if one is already installed, the next usually needs an application.

Leaseholders should also check their lease. Most leases reserve external walls to the freeholder, so you will normally need written consent from the freeholder or managing agent before anything goes on the outside.

Managing agents will usually ask for the installer's drawings, the noise assessment, and evidence of insurance. Certified installers keep these to hand.

Conservation areas

In a conservation area, the unit must not be on a wall or roof that fronts a highway, or nearer to a highway than the building. In practice, anything visible from the street needs a planning application.

Some councils also use Article 4 directions to remove permitted-development rights for alterations in particular streets. Check your council's conservation area pages for any direction covering your address.

Rear walls, light-wells, side returns and concealed roof positions are the normal solutions.

Listed buildings

Listed buildings do not have Class G permitted-development rights. Listed building consent is always required, whichever wall the unit is on, and planning permission may be needed too. Talk to the council's conservation officer early.

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Commercial premises

Planning for commercial air conditioning units follows different rules from householder permitted development, and commercial installations are not covered by the grant. Speak to your local planning authority about the specific building.

What installers handle for you

An MCS-certified installer will do the noise assessment, propose a location that meets the rules, draft the planning submission if one is needed, and apply for the £2,500 Boiler Upgrade Scheme grant on your behalf. You sign, they file.