Air conditioning for extensions and kitchen-diners in Richmond
In London, heat soaks into brick and concrete during the day and comes back out at night, which is when it is hardest to sleep. In Richmond, a side wall of a single-storey extension is usually the neatest place for the indoor unit.
An extension in Richmond with a roof lantern or large glazed doors can overheat quickly on a sunny afternoon. Richmond lies roughly 8 miles from central London, and we cover it as part of London. That includes the TW9 postcode district.
Prices in Richmond
For Richmond, expect roughly £1,895 to £5,845 per space, VAT included, adjusted for typical London rates. Prices here sit above the national middle, reflecting London labour rates and parking and access costs. What moves a quote in Richmond up or down is mostly pipe length, how high the outdoor unit goes, and whether a new electrical circuit is needed. For reference, the Large single option in Richmond (one 5–7 kW unit for a large glazed space) usually comes to about £2,695–£3,745.
Single unit
One 3.5–5 kW unit for a medium extension.
Large single
One 5–7 kW unit for a large glazed space.
Twin units
Two indoor units on a multi-split for long or L-shaped spaces.
Guide prices show VAT at 20%. HMRC treats most fixed air conditioners and air-to-air heat pumps installed in homes as energy-saving materials, zero-rated until 31 March 2027 when we supply and fit them. If your installation qualifies, your quote shows 0% VAT and a lower price. Servicing, repairs, cleaning and controls are charged at 20%.
Planning and permissions
Since 29 May 2025, England's permitted development rules allow larger outdoor units (up to 1.5 m³) and no longer require a 1 m gap to the boundary, provided the MCS 020(a) noise check is met. Listed buildings and pitched-roof installs still need permission.
The survey
A survey in Richmond usually takes one to two hours. We measure the rooms, check the walls and the consumer unit, agree the outdoor unit position with you and photograph the pipe routes. The free survey is where the real price is set: room measurements, pipe and drain routes, electrical checks and the outdoor unit position, all written into your quote.
What is included
Included as standard in Richmond:
- Handover of the remote or app
- One or two units sized for the whole space
- Placement clear of the hob and oven
- Hidden routes during the build, or neat surface routes after
- Free survey with glazing and roof heat-gain check
Nearby
We also cover Isleworth (2 miles), Hounslow (2 miles) and Barnes (3 miles). See all services in Richmond or air conditioning for extensions and kitchen-diners across London.