Air conditioning for extensions and kitchen-diners across Hertfordshire
In Watford, a side wall of a single-storey extension is usually the neatest place for the indoor unit. An extension in Watford with a roof lantern or large glazed doors can overheat quickly on a sunny afternoon. Low rainfall and long summer days in the East of England make south-facing rooms the first to overheat.
Prices in Hertfordshire
Our East of England guide price for air conditioning for extensions and kitchen-diners is £1,595–£4,995 per space, VAT included. The East of England is one of the dearer parts of the UK for trades, which shows in the range. Quotes move with the length of the pipe run, where the outdoor unit can sit and how much electrical work the job needs. For reference, the Large single option in Hertfordshire (one 5–7 kW unit for a large glazed space) usually comes to about £2,295–£3,195.
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
England's rules let most houses fit an outdoor unit without a planning application, as long as the size, number and MCS 020(a) noise conditions are met. Flats, listed buildings and roof-mounted units are treated differently.
The survey
At the survey we look at how each room is used, where the sun hits it and how the pipes can reach the outside wall, then put it all in a written quote. A survey in Hertfordshire 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.
What is included
Included with air conditioning for extensions and kitchen-diners across Hertfordshire:
- Placement clear of the hob and oven
- Pressure test, vacuum and commissioning
- One or two units sized for the whole space
- Free survey with glazing and roof heat-gain check
- Hidden routes during the build, or neat surface routes after
- Handover of the remote or app
Towns in Hertfordshire
Pick your town for local details, or see every service in Hertfordshire.