Standing in my kitchen in Yorkshire, I waited for my pyjamas to crisp up in the freezer, next to a bag of petit pois. It's a viral TikTok hack promising relief from the sticky heat that has been sweltering much of Europe. But as the novelty of wearing frozen clothes wore off within minutes, I realised this was no solution.
Yorkshire, known for its rainy weather and misty moors, hit 32°C this week. For southern Europeans accustomed to 40°C summers, that may not sound extreme. But only five to seven per cent of homes in the UK have air conditioning, houses are built to retain heat, and there is no siesta culture to escape the midday sun.
At 8pm, my thermostat read 24°C — a sign that keeping curtains shut, closing the conservatory, and opening windows only when the outside air is cooler had helped. But upstairs felt significantly hotter. The temperature was forecast to drop to 18°C overnight, just below the threshold for a 'tropical night' (where temperatures never fall below 20°C in 24 hours). Yet it promised to be an uncomfortable night.
Nighttime heat is a growing health risk
“Nighttime heat is often underestimated, but it can be particularly dangerous because people are typically at home and may not have access to cool, air-conditioned spaces,” Ruth Engle, a data scientist at the World Resources Institute, told me. “We often talk about the 'cumulative heat burden' — the idea that the longer people are exposed to heat, the greater the impact on their health. When homes remain hot overnight, people lose the opportunity to recover from daytime temperatures, increasing risks, especially for older adults and those with underlying health conditions.”
Studies have linked high nighttime temperatures to increased mortality. The UK Met Office warns that the likelihood of experiencing three consecutive tropical nights during July has increased significantly due to climate change. Daytime temperatures are also becoming a concern in northern locations. Leeds recently became the first UK city council to launch a 'Cool Space' scheme, opening 39 hubs, libraries, and leisure centres across the city to help residents beat the heat — a concept similar to the network of climate shelters that have emerged across Spain in recent years.
Does the viral TikTok hack work?
I took the frozen clothes from the freezer and got changed. It felt refreshing for a moment — like turning into an ice lolly. But the fabric holds very little heat energy compared to your body, so it warms back to room temperature within minutes. The relief was fleeting, much like turning your pillow in the night.
The UK government does not recommend freezing your pyjamas. Instead, it advises avoiding the sun during peak hours, using SPF, limiting physical activity, and wearing loose, light-coloured clothing. Spraying or sponging skin with cool water, or placing cold packs wrapped in a cloth under your armpits or on your neck, can also help.
Long-term solutions for keeping homes cool
When it comes to cooling the house, there is less advice. The UK Health Security Agency suggests keeping windows and curtains closed in rooms that face the sun during the day and opening windows when the air feels cooler outside than inside. But for those seeking more lasting solutions, two approaches stand out.
Cool roofs: painting your home white
A 2024 paper by UCL and the University of Exeter, published in Nature Cities, analysed the cooling effect that roofs painted white or other reflective colours would have had on London's air temperature between June and August 2018 — one of the city's hottest summers on record. Researchers found that if cool, light-coloured roofs had been widely installed throughout the city, London could have cooled by about 0.8°C on average, preventing an estimated 249 heat-related deaths. White roofs are common in hotter countries in southern Europe and North Africa, but remain rare in the UK. Light-coloured roofs absorb less radiant energy from the sun, lowering city temperatures and keeping indoor spaces cooler.
Solar panels: more than cheap power
Solar panels are primarily designed to reduce household electricity bills, but they also offer a cooling benefit. By shading the roof, they reduce the amount of heat absorbed by the building, helping to keep indoor temperatures lower during heatwaves. As Europe grapples with rising temperatures and the need for energy independence, solar panels represent a dual-purpose investment.
For Europeans without air conditioning, the key is to combine short-term measures — like keeping curtains closed and using cool water — with longer-term investments in building design and renewable energy. Freezing your pyjamas might make for a good TikTok video, but it won't keep you cool through the night.
