Temperatures in the U.K. surpassed records on Tuesday, as an Europe-wide heat wave pushed the mercury up to 104.5°F (40.3°C). The unprecedented weather caused major disruptions in a country whose infrastructure was designed for a damp, mild climate—train services were delayed amid fears of buckling tracks, while London Luton airport closed a runway after heat melted the tarmac.
A more personal level shows that many Brits are left feeling hot and uncomfortable due to the simple fact that only 5% of U.K. homes have air-conditioning. It’s a sharp contrast to the U.S., where the figure hovers above a whopping 90%. Some people were inspired to create their own air conditioning units by the lack of adequate cooling in the United Kingdom. There are even videos on social media of these makeshift units.
There are several reasons why few Brits have air-conditioning—the most obvious being the country’s relatively mild weather. Average summer temperatures range between 55°F (13°C) and 75°F (24°C), and winters can last up to five months. Because of the lower temperatures, British infrastructure was designed to be more efficient at heating. As heat waves become more severe and longer-lasting, it is more important to put more emphasis on cooling.
Continue reading: 5 Reasons Why the U.K. Was Not Built For Extreme Heat
Another key difference between the U.K. and the U.S., explains Smith Mordak, sustainability director at engineering consultancy Buro Happold, is the nature of the two countries’ housing stock. One in six English homes was built before 1900 according to U.K. government statistics, and 46% were constructed between 1930-1982. “[Air-conditioning] technology either wasn’t available or widespread then,” says Mordak, so most homes weren’t built to accommodate them. American homes are approximately 40 years old. Air-conditioning was standard in new buildings built after the 1960s.
While it’s possible to retrofit older houses with air-conditioning units, many are built with brick and have no—or very small—air cavities. It is therefore more difficult and costly to add air conditioning, especially if there are pre-existing electrical and hot water systems. It’s also common in the U.K. to live in what Brits call a “terraced” house—known as a row house in the U.S.—a property that shares a wall with the neighbors next door. This type of terraced home limits the choices for where the condenser (the outdoor part of the air-conditioning unit) can be installed.
Air-conditioning is not possible because of the way Brits heat homes. “British housing is heated primarily through water-based radiators, or ‘wet heat,’ and a smaller proportion of electric heating,” says Ian Hamilton, a professor at University College London’s Energy Institute. By contrast, the majority of homes in the U.S. are heated with “dry heat,” a warm air system using a gas- or oil-fired furnace. When it comes to installing an air-conditioning unit, Hamilton says, it’s “much more straightforward” to add to a dry heat system than a wet heat system. This is because “you maintain the way you distribute the heat or cooling effect—via the air—while switching between a furnace or A/C unit.”
While it’s rare to have air-conditioning in U.K. homes, it’s more common at work. It’s hard to determine exactly how prevalent air-conditioning is in offices, but a 2012 study by the Building Research Establishment estimated that 65% of office spaces and 30% of retail space in the U.K. have air-conditioning. Office buildings are typically more modern than British homes. Companies have greater resources to retrofit older buildings.
However, because of both the move to remote working as well as the disruption caused by heat to public transport, many British workers were forced to work from home Monday through Tuesday.
Hamilton says that despite periodic sales spikes, air-conditioning units will not become widely used in the U.K. until summer heat waves are more frequent and last for longer. But climate change is pushing the world in this direction—a recent study shows that Europe is a heat wave hotspot, with temperature extremes increasing three to four times faster than regions on similar latitudes, partly due to changes in the jet stream—air currents five to seven miles above Earth’s surface.
Continue reading: The Summer is becoming unbearably hot before it even starts
Ultimately, experts tell TIME that more air-conditioning units in the U.K. isn’t the answer to extreme heat. While air-conditioning units emit carbon dioxide that can contribute to climate change and the creation of new units will require the destructive extraction of rare metals, this would be harmful for the environment. To achieve its target of net zero, the U.K. government should, according to Mordak, be reconfiguring buildings and cities to promote “passive” methods of cooling—insulation, shading and tree planting—rather than energy-guzzling cooling systems.
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