What size air conditioning unit do I need?
A plain-English guide to kW sizing for UK rooms, including sun, windows and room use.
Rule of thumb
Most UK bedrooms need a 2.0–2.5 kW unit. Larger living rooms often need 3.5 kW, and open-plan spaces or conservatories 5 kW or more.
Things that increase the size needed
South-facing rooms, large windows, rooflights, loft rooms, kitchens and rooms with lots of people or computers.
Get it confirmed
Our calculator gives an indicative figure. Final equipment sizing should always be confirmed by an installer after a survey.
Work out your likely cost
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