Installation
The install journey: the process step by step, planning permission, F-Gas regulations, and what to expect on the day.
How to get air conditioning installed
Getting air conditioning installed is more involved than buying the unit, and it helps to know what happens before anyone turns up at your door. This is the place to understand the process, the legal side and what a typical job looks like, so there are no surprises on the day.
A standard single-room split is fitted by mounting the indoor unit on a wall, siting the outdoor condenser, and running a small pipe and cable between the two through a cored hole. Most single-room jobs take about a day. Our guide to how air conditioning is installed walks through each step, from survey to commissioning, so you can picture the work and prepare the space.
The part that catches people out is the law. A refrigerant split must legally be fitted by an F-Gas certified engineer, and doing that in-scope work without certification is an offence, so this is not a DIY job. Planning rules matter too. In England a cooling-only unit usually needs full planning permission, while a reverse-cycle unit that both heats and cools is often permitted development, subject to conditions that include a noise limit assessed under MCS 020. Our guide to whether you need planning permission explains where you stand.
It is worth knowing the rough cost before you commit. A single wall split is around £1,500 to £3,000 supplied and fitted, and any certified electrical work needed for the supply adds roughly £400 to £700 on top. The guides below are written to help you plan the job properly and know what to expect, not to rush you into booking anything.
Installation guides
How is air conditioning installed?
A plain-English walkthrough of how air conditioning is installed in a UK home, step by step, plus how long it takes, the F-Gas rules and why fitting a split is not a DIY job.
13 Jun 2026
Do you need planning permission for air conditioning?
A cooling-only unit usually needs full planning permission in England, while a reverse-cycle (heat and cool) unit is often permitted development. Here are the rules, the conditions and the exceptions.
6 Jun 2026Air conditioning installation: common questions
How is air conditioning installed? +
A fitter mounts the indoor unit on an internal wall, places the outdoor condenser outside, and connects the two with refrigerant pipework and a cable run through a small cored hole. The system is then wired in, the refrigerant circuit is checked, and the unit is commissioned and tested. A typical single-room install takes about a day.
Can I install air conditioning myself? +
No. A refrigerant split must legally be fitted by an F-Gas certified engineer, and doing that in-scope work without certification is an offence. You can prepare the space, but the installation itself has to be carried out by a qualified professional.
Do I need planning permission for air conditioning? +
It depends on the type of unit. In England a cooling-only unit usually needs full planning permission, while a reverse-cycle unit that both heats and cools is often permitted development, subject to conditions that include a noise limit assessed under MCS 020. It is worth confirming your own position before you book the work.
How long does an installation take? +
A typical single-room install takes about a day, including commissioning and testing. Larger multi-room or ducted systems take longer, but for one wall-mounted split you can usually expect the work to be finished within a day.
More guides
For the money side, our cost guides cover what it takes to buy and run a system, and our buying guides help you choose the right unit in the first place. You can also browse every guide in one place.
Find someone to fit it
A fitted system must be installed by an F-Gas registered engineer. Compare accredited installers near you, or browse the units they fit.