The number of people investing in air conditioning units is on the rise - especially in this heatwave. But there are some important things to consider before you splash out14:18, 25 Jun 2026Updated 14:19, 25 Jun 2026If you're sitting at home melting and frantically searching for air conditioning units online, you're not alone.‌With UK temperatures soaring up to 37°C in some regions, people are desperately trying to find ways to notoriously ill-equipped - and for many of us, standard electric fans just aren't cutting it.‌British houses are extreme heat to deal with extreme heat. Traditionally, they are built to retain warmth using heavy-duty bricks, thick insulation, double or triple glazing, and thick roof tiles. So, in the midst of this our increasingly intense heatwaves, could it be time to invest in air conditioning?‌An estimated four million homes in the UK now have air conditioning - double the figure from just three years ago. But how to go about choosing the right type for your home, and what will it cost you?To get the lowdown, we spoke to industry experts: Ian Brown, senior commercial manager of AC Installations at British Gas - and Will Jones, home expert at Currys.‌Are air conditioning units necessary in the UK?"Air conditioning is becoming more popular in the UK as summers get warmer," notes Ian. "While it's not essential for every home, it can help make your living space more comfortable by keeping rooms cool, reducing humidity and improving air circulation. Many modern systems can also provide heating during colder months, so they can be useful throughout the year rather than just during a heatwave."Will agrees: "Air conditioning was once seen as a luxury in the UK, but as heatwaves become more frequent and homes retain more heat, it's becoming an increasingly practical investment for many households."Portable air conditioners are particularly popular because they don't require permanent installation and can be used wherever cooling is needed most. Many models also offer heating, dehumidifying and fan functions, making them a useful year round appliance rather than something you'll only use for a few weeks each summer."‌How much do they cost to buy?According to Ian, the upfront cost depends on the type of system you choose and the size of your home: "Portable units are usually the cheapest option, while wall-mounted systems require installation but offer a more permanent solution. Larger systems that heat or cool multiple rooms will typically cost more"."There's an option to suit most budgets," says Will. "Portable air conditioners start from around £269 for entry-level models such as the Logik LAC07C25, while premium smart models like the Meaco MeacoCool range cost up to around £529."If you're looking for a permanent solution, professionally installed wall mounted systems from brands such as Toshiba typically start at around £2,500 and can exceed £3,200, including installation."‌What are the different types?Portable units: These can be moved from room to room and don't require installation.Wall-mounted split system: There are permanently fixed in place and are designed to cool or heat a room efficiently. There are also multi-room systems that can control the temperature in several rooms at once.‌Will adds: "Portable units are flexible, simple to set up and ideal for renters, flats or homes where permanent installation isn't practical. Fixed split systems provide more powerful, quieter cooling and often greater energy efficiency, but they require professional installation and a higher upfront investment."How much do they cost to run?According to independent testing by Which?, the average portable air conditioner costs 22p per hour on its highest setting. The cheapest they tested cost about 17p per hour to run, while the priciest hit 31p per hour.Data from MoneySuperMarket notes that running costs depend on the unit’s efficiency rating, usage level and your electricity tariff. On average, a modern A-rated split system costs between 10p and 50p per hour to run for cooling. Larger or older units may cost more, while inverter technology helps keep consumption low.‌To reduce running costs, choose an energy-efficient model, cool only the rooms you need, and make use of eco-modes and timers.Will calculates a real-world estimate based on a standard energy tariff:Portable unit: A typical 1,200-watt portable air conditioner running for eight hours a day costs around £2.50 per day, adding £75 a month to your bill.Wall-mounted split systems: Generally these cost between 20p and 54p per hour to run, depending on their size and workload. Choosing the right sized unit, closing windows and curtains, and using features such as eco mode, timers and sleep settings can all help reduce running costs.‌How effective are portable units?"Portable air conditioners are very effective at cooling individual rooms when they're correctly matched to the size of the space," Will says."The key is choosing the right BTU (British Thermal Unit) rating. A unit that is too small will struggle to cool efficiently, while one that's oversized may cool the room quickly without removing enough humidity, leaving it feeling less comfortable."‌Ian notes: "They're often popular with renters or people looking for a lower-cost way to stay comfortable during warmer weather. However, if you're looking for cheaper long-term running costs and heating, wall-mounted air conditioning is a no-brainer."Choosing the right BTU rating for your spaceWill says, that once you've matched the capacity to the room, "look at energy efficiency, noise levels and additional features such as dehumidifying, heating, timers and smart controls."Up to 14m² (Small bedrooms): Look for a 7,000 BTU unit.Up to 20m² (Standard bedrooms / small living room): Look for a 9,000 BTU unit.20m² and above (Large living rooms): Requires 12,000 BTU or more.‌Practically, what do portable ones need?"They're straightforward to set up," Will confirms. "Simply plug the unit in, position the exhaust hose through an open window using the supplied window kit, and you're ready to go."You'll need to consider moisture. In very humid conditions, some models may occasionally need the water tank emptied, although many modern units use self-evaporating technology, so manual draining is rarely required.Are air-conditioning units noisy?"Modern air conditioning systems are typically much quieter than many people expect," Ian notes. "Most are designed to run quietly in the background while keeping your home at a comfortable temperature."‌Portable air conditioners are louder, warns Will, because the compressor sits inside the room.He adds: "Most operate between 50 and 65 decibels, similar to the level of a normal conversation. If you're using one overnight, it's worth choosing a model with a dedicated sleep or night mode, which reduces both noise and energy consumption."‌Which is better, portable or wall-mounted?Both Ian and Will agree that it depends on your needs. "Portable units are more affordable upfront and can be moved around the home, while wall-mounted systems tend to be quieter, more efficient and better suited to people looking for a long-term heating and cooling solution," Ian told us.Will added: "If you're looking for a long-term solution with quieter operation and stronger performance, a professionally installed wall mounted system is likely to be the better option."‌What should buyers look out for?"Room size should always be the starting point, followed by the correct BTU rating, energy efficiency and noise levels," Will says. "It's worth looking for Energy Class A or A+ models, along with features such as eco mode, programmable timers, and sleep settings to help minimise energy use. Many models also double as dehumidifiers and fans, while some offer heating and smart app controls, giving you much more than just cooling."Best overall models to buyIf you're looking to buy, Will recommends three standout models:‌Best overall: MeacoCool MC12000RPRO Smart Air Conditioner & Dehumidifier, "thanks to its excellent cooling performance, relatively quiet operation and smart connectivity.Premium option: De'Longhi Pinguino EX130CST Smart Air Conditioner & Dehumidifier offers powerful cooling and app control. Best multi-taskerL "The Igenix IG9909WIFI 4-in-1 Portable Air Conditioner is another excellent choice, says Will, "combining cooling, heating, fan and dehumidifier functions in one unit."British Gas, meanwhile. recommend and stock Bosch air conditioning units, which are popular for their advanced technology, quiet performance and high quality.Could air conditioning add value to a home?"There's no guarantee that installing air conditioning will increase a property's value, but buyer expectations are changing as hotter summers become more common," Will says.‌"Portable units offer a simple, non-permanent way to improve comfort during heatwaves, while professionally installed systems can make a home more appealing to buyers looking for year-round climate control. If you'll regularly use both the cooling and heating functions, a fixed system can also represent a worthwhile long term investment."Do I need planning permission?In the vast majority of case, you generally do not need planning permission, but your system must meet all of the following criteria:System Type: The system must be capable of providing both heating and cooling (operating an air source heat pump). Units that offer cooling only usually require permission.Size Limits: The external compressor unit fixed outside your house must not exceed 0.6 cubic metres in volume.Location: It cannot be installed on a pitched roof. If placed on a flat roof, it must be at least 1 metre from the roof edge. The external unit must be at least 1 metre away from your property boundary.Elevation: The unit should not be placed on a wall or roof that faces a public road/highway‌When you will have to apply for planning permission:You will almost certainly need to submit a planning application if your property is any of the following:Flats or Apartments: Flats and shared buildings do not benefit from permitted development rights for external equipment.Listed Buildings: You will need Listed Building Consent, as preserving the historic fabric of the property is strictly regulated.Conservation Areas or Designated Land: Tighter rules apply here, meaning your unit must be hidden from street view and have a minimal visual impact.Multiple or Oversized Units: Installing more than the permitted number of units or a unit larger than the 0.6 cubic metre limit requires approval.Commercial Properties: Commercial premises have different, generally more stringent rules than domestic properties.Article continues belowAll installations must comply with strict electrical, safety, and energy efficiency building regulations.