Southwark: air conditioning planning permission

Since 2025-05-29, England's permitted-development rules let a house fit an air-to-air heat pump - which heats as well as cools - without a planning application in many cases, within set size, siting and noise limits. A cooling-only air conditioning unit does not get that route and needs a full planning application in Southwark whatever the property, because on its own it only cools.

Picking a system in Southwark therefore decides your planning path as much as your comfort. A unit that heats and cools opens up the permitted-development route on a house; one that only cools never does. Roughly 18% of Southwark's EPC-certified homes fall inside a conservation area, concentrated in areas like Trafalgar Avenue, Addington Square, Borough High Street - most addresses are outside one, but the boundary check is worth doing before committing to a wall-mounted unit.

Flats are the sharpest exception here as everywhere in England: the permitted-development right for an outdoor unit sits with the house, not the flat, so a Southwark flat will usually need both freeholder or managing-agent consent and planning permission.

Southwark lands close to the national middle on conservation coverage - about 17.9% of properties, including parts of Trafalgar Avenue, Addington Square and Borough High Street. With no clear-cut high or low figure to lean on, the permitted-development answer for an outdoor unit here turns more on your exact location than the borough-wide average.

91.9% of the 62 planning applications mentioning air conditioning or other cooling plant that Southwark has decided were approved, a figure covering all development types and including 20 householder applications.

In counts rather than proportions that is 57 approvals against 5 refusals.

Narrowing to the 20 householder applications on their own, which is the closest this data gets to your own case, 90% were approved.

The match is on the wording of each application, so this counts applications that mention cooling equipment rather than every cooling installation Southwark has seen.

Separately, and as a genuinely different question: Southwark has decided 107 applications mentioning an air-source heat pump, approving 97.2% of them. Most air-source schemes are about heating rather than cooling, the two sets overlap wherever an application mentions both, and the counts are never added together.

What actually gets refused, and what councils attach when they approve, is a national picture rather than a local one at the volume of officer reasoning currently published. We set both out with their sample sizes: why cooling applications get refused and the conditions councils attach.

You can also compare what each council decides, where enough decisions exist to publish a figure.

Background noise in Southwark sits around 55 dB across the property types we profile during the day, which is the level any outdoor unit has to live inside. A machine that is inaudible on a busy street can be the dominant sound in a still garden, so the local baseline changes the answer.

That makes placement the thing to get right: distance from a neighbour's window, and distance from the boundary, do more for an application than the specification of the unit itself.

None of this is a dealbreaker: councils in Southwark approve outdoor units for homes like these all the time. Around 17.9% of local properties sit inside a conservation area, so it is a step to plan for rather than a formality. Being close to a listed building - around 6.7% of homes here sit within 30 metres of one is not the same as your home being listed, and public data can flag conservation status without settling it. This is indicative guidance, not legal advice: confirm the final position with your Local Planning Authority before you install.