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

Picking a system in Eastleigh 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. Conservation-area coverage in Eastleigh is genuinely low (around 2% of EPC-certified homes), so for most addresses an external unit is a lower-friction proposition than in a heritage-dense borough - an honest advantage, not a workaround.

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 Eastleigh flat will usually need both freeholder or managing-agent consent and planning permission.

Only around 1.8% of Eastleigh's properties sit inside a conservation area, a low share by national standards. That means most houses here clear the permitted-development bar for an outdoor unit without extra paperwork - though a flat will typically still need Eastleigh Council to issue planning permission.

100% of the 41 planning applications mentioning air conditioning or other cooling plant that Eastleigh has decided were approved, a figure covering all development types and including 14 householder applications.

The same figures as counts are 41 approved and 0 refused.

A householder-only rate would be the more useful number, and Eastleigh has not yet decided enough of them for one: 14 is below the sample size we publish a percentage from.

One more thing about the method: applications are identified from their own description, so the Eastleigh figures cover applications mentioning cooling equipment and will understate rather than overstate real activity.

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 Eastleigh sits around 43 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. Eastleigh's council approves outdoor units for homes like these routinely. Conservation-area coverage locally runs at around 1.8%, which makes this worth planning for rather than assuming. Proximity to a listed building - around 0.7% 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.