Do I need planning permission for air conditioning?
Short answer: for most UK houses, no. Domestic air conditioning falls under permitted development (Class G of the General Permitted Development Order), which means you can install it without a planning application — as long as it meets a handful of straightforward conditions.
When it IS allowed without permission
- Detached, semi-detached and terraced houses in England.
- Outdoor unit under 0.6 cubic metres (basically anything under 5kW domestic).
- At least 1 metre from the property boundary.
- Not on a wall that faces, and is within 3.5 metres of, a highway.
- Not within 1 metre of the edge of a flat roof.
- Noise level at neighbouring windows below 42 dB(A).
- Removed as soon as it's no longer needed.
When you DO need permission
- Flats or maisonettes — Class G doesn't apply, so a full application is needed.
- Listed buildings — you'll need Listed Building Consent whatever the size.
- Conservation areas — usually allowed, but a discreet install is essential.
- Any install that breaches the 42 dB(A) neighbour noise limit.
- Units mounted on the front of the house facing a public highway.
How we handle it for you
On the free survey we photograph the proposed location, check boundary distances, and estimate the noise at the nearest neighbour's window using the manufacturer's dB rating and distance. If the install falls under permitted development we tell you outright. If it doesn't, we quote the drawings and application separately (£350–£650 typical) so there are no surprises.