How much does air conditioning installation cost in London?

The short version

There is no single London price for air conditioning, and anyone who gives you one over the phone has not seen your home. What we can do is show you the published typical figures and then walk through the things that push a London job up or down. That way you can read a quote and see where the money is going.

The Energy Saving Trust gives these typical costs for air to air heat pumps, which use the same equipment as a reversible split air conditioner:

Job	Typical figure (Energy Saving Trust)
One room	about £1,900
Three bedroom semi detached house	around £3,700

Those numbers are a fair starting point for a straightforward house. Most London homes are not straightforward, which is why the rest of this guide matters.

What you are actually paying for

A split system quote is made up of a few clear parts. If a quote does not break these down, ask for it.

• The equipment: the indoor unit for each room, one outdoor unit, and the remote or app controls. Bigger cooling output and quieter night modes cost more.
• Pipework and covers: insulated copper pipes, the cable and the condensate drain between the units, plus white trunking or covers where they run outside.
• Fixing the outdoor unit: wall brackets, a ground frame or a roof stand, and anti vibration mounts.
• The electrical connection: most installs need a dedicated circuit, which is notifiable work under Part P. See the Planning Portal electrics guidance.
• Commissioning: pressure testing, evacuating the pipes, setting the refrigerant charge and testing the system.
• Making good: filling around holes and tidying up after the work.

Why London jobs vary so much

Flats and access

The 2021 Census found that 54% of London households live in a flat, compared with about 22% across England and Wales (ONS). In a flat, the outdoor unit may have to go on a shared roof, in a lightwell or on a rear wall three storeys up. That can mean a long pipe run, a scaffold tower, or extra people to lift the unit safely. None of that shows up in a single room figure from a national survey.

The roof and the top floor

Top floor flats and loft conversions are the rooms Londoners most want cooled. They also tend to need a larger unit, because the roof takes the sun all day, and the pipes have further to travel down the house. A loft in a Wandsworth or Earlsfield terrace with a big rear dormer is a typical example. Our guide to loft conversion air conditioning covers that case in more depth.

Planning and consent

Planning fees and freeholder fees are real costs, and they sit outside the installer’s price. A reversible heat pump that also heats can be permitted development on a house if it meets every Class G limit, including a calculated noise level of 37 dB(A) at the neighbour’s window. A cooling only unit, most flats, listed buildings and street facing walls in conservation areas usually need an application. The Planning Portal lists the rules.

If you own a leasehold flat, expect a licence for alterations from the freeholder. Managing agents often charge for reviewing the request.

Noise limits in central boroughs

In parts of central London, the council’s noise rules shape the job. Westminster’s noise technical guidance asks for plant noise 10 dB below the lowest background level in noisy areas. Meeting that might mean a quieter outdoor unit, an acoustic enclosure or a different position, each of which changes the price.

A simple way to estimate your own job

Use this table to see which way your job is likely to move from the typical figures.

Factor	Tends to keep cost down	Tends to push cost up
Building	house with a garden	upper floor flat
Outdoor unit	ground level rear wall	roof, high wall, lightwell
Pipe run	short, straight through the wall	across the house, down several floors
Rooms	one room	several rooms on a multi split
Electrics	spare way in a modern consumer unit	old consumer unit needing work
Consent	permitted development	planning application and freeholder licence
Decoration	pipes in neat covers	pipes chased into walls or ceilings

What about running costs and grants?

The purchase price is only part of the picture. If you want the system to heat your home as well as cool it, it needs to be sized for winter heat loss. Done that way, it may qualify for the Boiler Upgrade Scheme, which now lists £2,500 towards an air to air heat pump. The conditions are strict. Ofgem requires an MCS certified installer, a home in England or Wales, and a system that replaces fossil fuel or electric heating. As of 20 October 2026, the Energy Saving Trust says there are no MCS certified air to air installers yet. A cooling only system will not qualify in any case.

How to compare quotes

When you get two or three quotes, line them up on the same points:

1. Exact make and model of each unit, with cooling and heating output.
2. Where the outdoor unit goes, and whether the installer has checked the noise at the nearest window.
3. Pipe length included, and the price for any extra.
4. Whether the electrical circuit is included and who certifies it under Part P.
5. The company’s F-gas certificate number, which you can check on the Refcom or F-Gas Register site.
6. What is excluded: planning fees, freeholder fees, decorating, scaffolding.

A much cheaper quote often leaves something out, such as the electrics, the condensate route or the noise check.

Getting a real price for your home

The fastest way to a firm figure is a survey. We measure each room, look at the outside walls and roof, check the electrics and tell you what consent is needed before you commit. You can see how we plan a job on the home air conditioning page, and if you live in Battersea, Putney or Tooting, the Wandsworth area page covers the local housing and planning points.