Air conditioning for extensions and kitchen-diners in Portsmouth
In Portsmouth, a side wall of a single-storey extension is usually the neatest place for the indoor unit. Summers in the South East are among the warmest in the country, so cooling often comes first, with efficient winter heating as a bonus.
For a kitchen-diner in Portsmouth, we place the indoor unit clear of the hob and plan the outdoor unit at the rear. Portsmouth sits around 15 miles from Southampton, inside our Hampshire area. We cover PO5 and the streets around them.
Prices in Portsmouth
Guide prices around Portsmouth run from £1,745 to £5,445 per space including VAT. That is above the UK middle, mainly because labour and access cost more in South East England. The biggest variables are the pipe route, access for the outdoor unit and the state of the consumer unit, all of which the survey settles. As an example, the Large single option (one 5–7 kW unit for a large glazed space) would typically be £2,495–£3,495 here.
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
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. A survey in Portsmouth 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
Every job in Portsmouth includes:
- One or two units sized for the whole space
- Free survey with glazing and roof heat-gain check
- Placement clear of the hob and oven
- Hidden routes during the build, or neat surface routes after
- Pressure test, vacuum and commissioning
Nearby
Neighbouring places we cover include Gosport (2 miles), Fareham (5 miles) and Havant (6 miles). See all services in Portsmouth or air conditioning for extensions and kitchen-diners across Hampshire.