Can you fit air conditioning at your address?
On a house in England, an air conditioner that also heats is usually permitted development — no planning application — if the outdoor unit is under 1.5 m³ and stays under 37 dB at the neighbour's window: a typical 2.5 kW unit needs about 6.3 m, the quietest tenth 4.5 m or less (715 models, manufacturer-declared; Class G, checked 25 Sep 2026). Enter your postcode for last summer's hot nights, your council's rule and a cooling path for your type of home.
Check your postcode
Everything on this site
- Do I need planning permission?
365 councils and 2,863 postcode districts, with the rule for each nation - Quietest air conditioners
98 shortlists by size, noise, efficiency and running cost - Compare two models
22,986 head-to-head comparisons: noise at the neighbour's window and £ per summer - Brands
123 brands, 8,673 model families registered for sale - Installers near you
53,899 plumbing, heating and air-conditioning companies in 4,561 towns - The £2,500 grant
Boiler Upgrade Scheme for air-to-air heat pumps, by region and council (330 pages) - What it costs fitted
A 2.5 kW split by region, from published UK price guides - Fans, portables and shading
812 products with price and £ per summer - Calculators
7 tools: room size, noise, planning, grant, running cost, payback, landlord letter - Common situations
Flats, terraces, rented homes, listed buildings, Scotland
Worked examples
- N1 · Islington · England
- CF10 · Cardiff · Wales
- EH1 · City of Edinburgh · Scotland
- Peak District National Park
- Daikin Perfera 2.5 kW (FTXM25A / RXM25A) · 58 dB(A) declared sound power