Greenwich: 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 Greenwich whatever the property, because on its own it only cools.

Picking a system in Greenwich 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 15% of Greenwich's EPC-certified homes fall inside a conservation area - 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 Greenwich flat will usually need both freeholder or managing-agent consent and planning permission.

Around 14.8% of Greenwich's properties sit inside a conservation area - a middling figure nationally, so the permitted-development position varies more by exact location here than in an area with a clear-cut high or low coverage figure.

We hold some decided cooling cases for Greenwich and not enough to say anything with. The sample-size floor is there precisely to stop a thin record turning into a confident-looking statistic.

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 Greenwich sits around 52 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.

Nothing here is a dealbreaker. Greenwich's council approves outdoor units for homes like these routinely. Conservation-area coverage locally runs at around 14.8%, which makes this worth planning for rather than assuming. Proximity to a listed building - around 2.5% of homes here sit within 30 metres of one does not mean your own home is listed, and public data can flag a conservation-area question without answering it. Treat this as indicative guidance, not legal advice, and confirm the final position with your Local Planning Authority before installing.