Often not. Since 29 May 2025, air-to-air heat pumps, which is what most home air conditioning is, can be fitted to many houses in England under permitted development, so no planning application is needed. The unit still has to meet the conditions, and some homes are excluded. Always check your own situation with the Planning Portal or Derby City Council (or your local council) before you commit.
What changed in 2025
Before May 2025, permitted development rules in England only covered heat pumps used for heating. A wall unit that could also cool usually needed a planning application. The Town and Country Planning (General Permitted Development) (England) (Amendment) Order 2025 changed that, so air-to-air heat pumps used for heating and cooling are now included. The same changes also relaxed some of the old size and distance limits.
The main things to check
The rules are detailed, and they can change, so treat this as a starting point rather than the final word:
- The size of the outdoor unit. There's a limit on how big it can be. Most single-room units are well inside it, but some larger models aren't.
- Noise. The unit has to meet the noise limits set out in the MCS planning standard (MCS 020). Where the unit sits in relation to your neighbours' windows matters.
- Where it goes on the house. There are rules about the position of the outdoor unit, especially on walls facing a road.
- How many units. There are limits on the number of outdoor units.
When you may still need permission
- Listed buildings need listed building consent.
- Conservation areas have tighter rules, particularly for walls facing a road.
- Flats and maisonettes are treated differently from houses.
- Article 4 directions can remove permitted development rights in some areas.
Other permissions to think about
Planning isn't the only question. If you're in a flat or a leasehold house, check your lease and ask the freeholder. If you rent, you'll need your landlord's agreement. And if the unit is going on a shared wall, it's polite (and sensible) to talk to your neighbours first.
Fitted properly
Planning is only part of it. Fitting air conditioning means handling refrigerant gas, which needs F-gas certification. Josh holds an F-gas certificate and is a member of REFCOM. We also test the electrical work and certify it to BS 7671.
We'll flag anything at the visit
When we come out to look at the room and where the outdoor unit could go, we'll tell you if anything looks like it might need checking with the council. See air conditioning with JJS Electrical, read how much air conditioning costs in Derby, or ask for a free visit.
