Air Conditioning: Your Complete Guide
Air conditioning used to be a rarity in UK homes, but with summers getting warmer year on year, it is fast becoming a sensible investment. This guide covers the different types, what they cost, how much they cost to run, and what you need to know about installation rules — including F-gas regulations that require installers to be certified.
Types of air conditioning
Wall-mounted split system
The most popular choice for UK homes. One indoor unit mounts high on the wall, connected to an outdoor unit by refrigerant pipes. Efficient, quiet, and can heat as well as cool. Ideal for single rooms.
Multi-split system
One outdoor unit serves two to four indoor units in different rooms. More economical than fitting separate systems for each room. Good for open-plan spaces or homes that need cooling in multiple bedrooms.
Ducted system
Completely concealed - the indoor unit sits in a ceiling void and distributes air through ducts and grilles. The most discreet option but the most expensive. Best suited to new builds or major renovations where you can route ductwork easily.
Portable unit
A freestanding unit that vents hot air through a flexible hose to a window. No installation needed, so it is the cheapest upfront. But portable units are noisy, inefficient, and do not cool as effectively as a proper split system.
Air conditioning guides
Air conditioning cost guide
Installation prices, running costs, and how to get the best deal on air conditioning in 2026.
Split system AC cost
Single and multi-split prices, running costs, brands, and whether it can replace your heating.
Heat pump cost guide
Air source and ground source heat pump prices, grants, and running costs.
Insulation cost guide
Better insulation keeps cool air in during summer and warm air in during winter.
Common questions
Is air conditioning worth it in the UK?
UK summers are getting warmer, and heatwaves are becoming more frequent. If your home gets uncomfortably hot in summer - especially south-facing rooms, loft conversions, or conservatories - air conditioning makes a genuine difference. Modern units also work as heat pumps, providing efficient heating in winter, which can reduce your gas bills.
How much does air conditioning cost to run?
A typical wall-mounted unit costs 8–15p per hour to run for cooling. Running it 8 hours daily during a hot spell costs roughly £25–£50 per month. Modern inverter units are much cheaper to run than portable units, which can cost 20–30p per hour and are far less efficient.
What types of air conditioning are there for homes?
The main types are: wall-mounted split units (most popular, one indoor and one outdoor unit), multi-split systems (one outdoor unit serving multiple rooms), ducted systems (concealed in ceiling voids), and portable units (no installation needed but least efficient). For most UK homes, a wall-mounted split unit offers the best balance of cost, efficiency, and performance.
Do I need planning permission?
Not usually, under permitted development rights. But if you live in a listed building, conservation area, or a flat with a leasehold, you may need permission. The outdoor unit should also be positioned to minimise noise disturbance to neighbours.
Getting the best deal on air conditioning
Get at least three written quotes
Air conditioning installation prices vary significantly between engineers. The same split system can differ by hundreds of pounds depending on the installer, their overheads, and how busy they are. Always get at least three written quotes from F-Gas registered engineers so you can compare like for like — the same unit, the same pipe run, and the same warranty. A written quote also protects you if the job ends up costing more than expected.