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Planning guide · UK rules, October 2026
Do you need planning permission for air conditioning?
For most homes in England and Wales, no. Scotland, Northern Ireland, listed buildings and businesses have different rules. Here's what's allowed, where units can go, and when you need to apply.
The quick answer
Usually not, for homes in England and Wales
- No permissionA home system that heats and cools (an air-to-air heat pump) is usually permitted development in England and Wales, if it meets the size, position and noise rules.
- Check firstListed buildings, conservation areas, flats, Scotland and Northern Ireland have tighter rules, especially for cooling.
- Usually applyShops, offices and other businesses normally need planning permission for outdoor units.
Rules by country
The rules in England, Wales, Scotland and Northern Ireland
Planning is devolved, so each nation has its own permitted development rules for homes.
England
Rules updated 29 May 2025- Air conditioning that also heats (air-to-air heat pumps) is covered. Cooling-only units are not
- Up to 2 outdoor units on a detached house, 1 on other houses and blocks of flats
- Outdoor unit up to 1.5m³ (0.6m³ on a block of flats)
- No minimum distance from the boundary
- Must meet the MCS 020 a) noise standard
Wales
Rules updated 1 June 2026- Air-to-air heat pumps are now covered
- Up to 2 units on a detached house, if both together meet the noise limit
- Outdoor unit up to 1.5m³
- The old 3 metre boundary rule has been removed
- Must meet the MCS 020(a) noise standard
Scotland
Class 6H rules- Permitted development only covers heat pumps used for heating or hot water
- Air conditioning used for cooling usually needs planning permission
- 1 unit per building, no more than 3m high
- Not in front of a wall facing a road
- Conservation areas: ground floor, rear wall only
Northern Ireland
Rules updated 4 July 2023- Covers heat pumps used to provide heating. Units used for cooling may need permission
- 1 unit per property, at least 1m from a neighbour's boundary
- Not on a roof, and no more than 3m high
- Not in front of a wall facing a road
- Must meet the MCS 020 standard
Permitted development means you can install without applying for planning permission, as long as every condition is met. Your council can remove these rights in some areas with an Article 4 Direction, so we always check your address first.
Where it can go
Where you can and can't put the outdoor unit
Usually allowed
- On the ground in your back or side garden
- On a back or side wall, at ground floor level
- On a back or side wall at upper levels, if the wall doesn't face a road (England)
- On a flat roof, at least 1m from the edge (England)
Needs planning permission
- On a pitched (sloping) roof
- On a wall facing a road, above ground floor level (England)
- On a wall or roof facing a road in a conservation area or World Heritage Site
- Anywhere on a listed building or in its grounds
- Cooling-only units, without a heat pump
Side by side
Permitted development for homes at a glance
| Rule | England | Wales | Scotland | N. Ireland |
|---|---|---|---|---|
| Heating and cooling units | Yes, if not cooling-only | Yes | Heating only | Heating only |
| Units allowed | 2 detached, 1 other | 2 detached, 1 other | 1 per building | 1 per property |
| Outdoor unit size | Up to 1.5m³ | Up to 1.5m³ | Max 3m high | Max 3m high |
| Distance from boundary | No minimum | No minimum | No minimum | At least 1m |
| On a roof | Flat roof only, 1m from edge | Check limits | Max 1m above roof | Not allowed |
| Wall facing a road | Ground floor only | Allowed outside conservation areas | Not allowed | Not allowed |
| Conservation areas | Not facing a road | Not facing a road | Ground floor, rear only | Not visible from a road |
| Listed buildings | Needs permission | Needs permission | Needs permission | Needs consent |
| Noise standard | MCS 020 a) | MCS 020(a) | MCS standards | MCS 020 |
When to apply
When you will need planning permission
If any of these apply to you, you'll usually need to apply to your local council before installation.
- Your home is a listed building, or the unit goes in its grounds
- You live in a conservation area and the unit would face a road
- Your council has an Article 4 Direction removing permitted development rights
- You want more units than allowed, or a bigger outdoor unit
- The unit would sit on a pitched roof or high on a wall facing a road
- The installation can't meet the MCS 020 noise standard
- It's a commercial building (see below)
- You're in Scotland and want the system for cooling
Other permissions
Other consents you might need
Planning isn't the only thing to check. These apply whether or not you need planning permission.
Listed building consent
Any work to a listed building, inside or out, needs listed building consent as well as planning permission.
Landlord or freeholder
Flats, leasehold homes and rented business premises usually need written permission under the lease.
F-Gas certification
By law, refrigerant work must be done by an F-Gas certified engineer. All our engineers are certified.
Electrical safety
The new electrical supply must meet the Building Regulations (Part P in England and Wales) and be certified.
Noise
Even with permission, a unit must not cause a noise nuisance. Good positioning and modern quiet units avoid this.
Article 4 areas
Some councils remove permitted development rights in certain streets. We check your address before we install.
For businesses
Planning permission for shops, offices and commercial buildings
In England, the permitted development rules for air source heat pumps only cover houses and blocks of flats. Outdoor units on shops, offices, restaurants, salons, warehouses and other commercial buildings usually need planning permission, especially on a roof, a front wall or in a conservation area.
Rented premises will also need your landlord's consent. Larger systems may need a noise assessment as part of the application.
How we help businesses
- Free site survey to find the best position for the outdoor units
- Unit specifications, drawings and noise data for your planning application
- Advice on what your council is likely to ask for
- Out-of-hours installation once you have approval
How we help
We check planning before we install
You don't need to work any of this out yourself. Our team checks every installation against the rules for your address.
We check your address
We look up whether you're in a conservation area or a listed building, and whether any Article 4 Direction applies.
We plan the position
We choose an outdoor unit position that meets the size, position and noise rules, so most homes don't need to apply.
We run the noise check
We complete the MCS 020 noise calculation for your installation and keep a record.
We tell you if you need to apply
If planning permission or another consent is needed, we tell you before you pay, and provide the technical details for your application.
We install
Our F-Gas certified engineers fit your system, usually in a day for a single room.
You get the paperwork
You receive your F-Gas certificate, electrical certificate and warranty details.
FAQs
Planning permission questions
Still unsure? Call us on 0330 043 7869, 7 days a week.
Do I need planning permission for air conditioning in England?
Usually not, as long as the system is an air-to-air heat pump that heats as well as cools, meets the MCS 020 a) noise standard and follows the size and position limits. Since 29 May 2025 these systems are permitted development. Listed buildings, some conservation area positions and cooling-only units need permission.
Are cooling-only air conditioning units allowed without permission?
No. In England the rules only apply if the unit is not used solely for cooling. Every home system we install is a heat pump that heats and cools, so it can qualify.
How close to my neighbour's boundary can the outdoor unit be?
In England and Wales there is no longer a minimum distance, but the unit must meet the noise standard at your neighbour's nearest window or door. In Northern Ireland it must be at least 1 metre from the boundary of a neighbouring property.
I live in a flat. Can I have air conditioning?
In England one unit is allowed on a block of flats, with a smaller outdoor unit of up to 0.6m³. You'll usually also need permission from your landlord or freeholder under your lease, and agreement for any work to shared walls or roofs.
Do I need planning permission for air conditioning at my business?
Usually yes. In England the permitted development rules for air source heat pumps only cover houses and blocks of flats, not shops, offices or other commercial buildings. We'll tell you what's needed and provide the technical and noise details for your application.
What happens if I install without permission when I needed it?
Your council can ask you to apply for retrospective permission, move the unit or remove it. It can also cause problems when you sell. That's why we check before we install.
Do I need Building Regulations approval?
Not usually for the unit itself, but the electrical connection must meet the Building Regulations (Part P in England and Wales), and the refrigerant work must be done by an F-Gas certified engineer. We handle both and give you the certificates.
Let us check your home or business for you
Prefer to talk? Call 0330 043 7869, 7 days a week.