As the UK heads into summer, many people are wondering how they’ll cope if another major heatwave hits. In 2022, the country recorded its hottest temperature ever, reaching 40.3°C (104.5°F) in eastern England. Despite increasingly hot summers, air conditioning is still rare in Britain, with fewer than 5 percent of homes having it installed. As temperatures continue to rise, the issue is becoming more than just a matter of comfort. It affects sleep, health, productivity, and raises important questions about whether Britain’s homes are prepared for a warmer future.
One reason air conditioning is so rare is that Britain’s homes are old. About four in ten were built before World War II, long before air conditioning was available. These homes were designed to keep people warm during cold winters, not cool during summer heat.
Newer homes aren’t much different. Building regulations introduced in 2021 prioritized energy efficiency, encouraging developers to rely on insulation, ventilation, shading, and window placement to prevent overheating. In London, local planning guidance puts air conditioning at the bottom of the list of preferred solutions. Developers are expected to try other methods first. The problem is that these passive cooling measures don’t always work during a serious heatwave. Opening windows and improving airflow can help on warm days, but when temperatures stay high for days at a time, many homes still become uncomfortably hot.
Another reason air conditioning remains uncommon is cost and practicality. Installing it increases building costs, which are usually passed on to buyers. Retrofitting older homes is even more challenging, since many weren’t designed for modern cooling systems. Installation can mean bulky external units, visible pipework, or major structural changes, and in some listed or older properties it may not be allowed at all.
If air conditioning became standard across millions of homes, it would also significantly increase electricity demand during heatwaves, when usage is already at its peak. That raises concerns about pressure on the UK’s energy grid and the need for major infrastructure upgrades.
The UK has run into energy crunch moments before, usually in winter when everyone turns their heating up at the same time. In those situations, the grid has had to lean on backup power and emergency measures just to keep everything running smoothly. Now imagine the same kind of sudden spike, but in summer instead, with millions of air conditioners switching on during a heatwave. It’s a similar kind of stress on the system, just in the opposite direction, and it would push an infrastructure that was mostly built around winter heating into completely new territory.
