In most cases, you do not need planning permission for air conditioning, especially if it would not affect the building’s appearance from the outside. There is no single blanket rule, though, and it is always worth checking with your local council. The rules also differ between homes and commercial properties and between houses and flats, so what applies to one property will not always apply to another.
| Property type | Planning permission usually needed? | Key condition |
| House (heating and cooling air-to-air heat pump) | Usually no | Must meet permitted development conditions |
| House (cooling unit only) | Often no but assessed case by case | No dedicated permitted development right, depends on siting and appearance |
| Flat or maisonette | Likely | Permitted development rights are more restricted |
| Listed building | Yes | Planning permission plus listed building consent |
| Conservation area or National park | Often yes | Rights may be restricted or removed by an Article 4 direction |
| Commercial premises | Usually yes | Larger systems, noise and visual impact are assessed |
Even when planning permission is not required, an air conditioning unit must not cause a noise nuisance to neighbours. Councils can take enforcement action if it does.
No, air conditioning has not been banned in UK homes. There was widespread, unfounded information that it was due to separate building regulations that require new homes to be designed with minimising overheating in mind. The rules are about designing cooler homes, not banning air conditioning. Confusion appeared to be rife among many property owners, leading the Ministry of Housing, Communities and Local Government to even go so far as to write a blog confirming air conditioning is not banned.
Whether you need planning permission for your air conditioning depends on the type of unit you are installing, the type of property it’s being installed in and where the air con unit is positioned.
Permitted development rights in England apply to air source heat pumps, and this is something many guides miss. Since May 2025, those rights have covered air-to-air heat pumps that provide cooling and heating, provided the system is not only used to cool the property. A unit that only cools has no dedicated permitted development rights of its own. Instead, the need for planning permission is based on whether the unit affects the building’s external appearance.
In practice, a heating-and-cooling air-to-air heat pump can qualify for permitted developments if it meets specific conditions. In many cases, a small, discreet cooling-only unit will often not need planning permission, but it’s wrong to assume this is always the case. Check with your local council for clarity before booking an installation.
For larger units, sensitive locations or an installation that may be considered an eyesore, the need for planning permission is much more likely.
Permitted development rights for air conditioning are rights that allow work to go ahead without any need for an application, as long as certain conditions are met. For an air source heat pump, including an air-to-air heat pump that also cools, the current rules in England are:
| Condition | Requirement (Houses) |
| Certification | Must comply with the MCS 020(a) planning standard |
| Unit volume | No larger than 1.5 cubic metres on a house (0.6 cubic metres on a block of flats) |
| Number of units | First two units on a detached house, first unit only on other houses and flats |
| Boundary distance | No longer applies |
| Placement (general) | Allowed on a front wall fronting a highway, but only at ground floor level |
| Placement (conservation area or heritage site) | Not on a wall or roof that fronts a highway, and not nearer the highway than the nearest part of the building |
| Roof types | Not on a pitched roof. On flat roofs, must be set at least one metre from the outer edge |
| Noise | Must pass the MCS 020(a) noise assessment |
The May 2025 reform means that houses could now increase the volume of an air conditioning unit from 0.6 to 1.5 cubic metres, boundary rules would no longer exist, detached homes could have a second unit and air-to-air heat pumps that also cool were now within scope.
You will normally need planning permission for air conditioning in the following situations:
In most cases, business premises require planning permission for an air conditioning installation. The units used tend to be much larger, more visible and much louder than domestic equivalents. Therefore, local councils assess them much more closely. Applications will often need a noise assessment and detailed plans showing where the units will be located.
There are several differences between planning permission requirements for air conditioning at commercial premises and residential ones; we outline them below.
| Factor | Home | Business |
| Default position | Often permitted development | Usually needs planning permission |
| System size | Typically small, single units | Large roof-mounted units, often multiple units per building |
| Main assessment | Appearance and noise | Noise, visual impact and character of the area |
| Extra documents | Rarely needed | Noise assessments & screening plans often required |
If you run a business, the safe assumption is that you need permission. To remain compliant, speak to your local planning authority before you get any work started.
Listed buildings need both planning permission and Listed Building Consent if you wish to have air conditioning installed. Listed Building Consent focuses on protecting the building, so external units would normally need concealing and damage to the original property features must be avoided.
In conservation areas, permitted development rights are restricted rather than removed, but for any visible external unit, you’ll normally need consent. Councils in conservation areas want to protect the buildings and their characteristics; a modern air con unit bolted on the side would do little to retain that authenticity. If you can prove the unit is discreetly sited and not prominent from the street, you may find your application is successful.
Planning permission and Building Regulations are often confused, but they are two separate legal requirements. Even if you do not need planning permission to install air conditioning, your installation must comply with Building Regulations and the related rules.
Using an accredited installer like Sussex Air Conditioning & Heat Pumps is the easiest way to ensure your installation is fully compliant.
Yes, it can. Permitted development is not a permanent guarantee. If an installation does not meet all the conditions, for example it exceeds the size limit or fails the MCS 020(a) noise assessment, then it was never lawfully a permitted development, and the council can take enforcement action that may require changes or removal.
Noise is the most common trigger. Even when planning permission is sound, an air con unit must not cause a nuisance to neighbours. If it does, the council’s environmental health team can request the noise be reduced, the unit altered or even removed, regardless of its planning status.
Before having air conditioning installed, take three simple steps:
Getting this right from the start avoids any potential legal issues, neighbour disputes and even the possibility of having to remove the unit if it is deemed non-compliant.
Ready to have air conditioning installed? Contact our team today. Our fully certified and F-gas compliant engineers are available across East and West Sussex to install, repair and service air conditioning units and heat pumps.