As the UK bakes in a record-breaking heatwave with temperatures reaching 40°C, people are desperate for quick cooling solutions. Social media's most talked-about trick involves taping tin foil across windows. But does it genuinely work? A reporter put it to the test and found a noticeable difference.
Tin Foil Hack Test: Results
Reach reporter Alex Evans stuck kitchen foil onto his windows overnight and measured the temperature in his home office against other parts of his property. He discovered a "noticeable difference." According to Alex: "I walked into this room at about midday and honestly, it was a noticeable difference. No lie, it's definitely the coolest part of the house. For a little cross comparison, I put the thermostat in the unfoiled dining room downstairs and within 30 minutes it said 36°C. I brought it back upstairs and put it in the office and it dropped instantly to 31°C in here."
Experts advise fixing the foil to the exterior of windows rather than the interior to stop the glass from overheating.
Common Heatwave Mistakes
Angus Struthers, Managing Director at heating and cooling specialists BOXT, explains common errors. Opening windows at the wrong time can make your home hotter: "If the air outside is warmer than the air inside, you're just letting more heat into the house. It's better to keep windows shut throughout the hottest part of the day and then open them up later in the evening once things cool down."
Fans also don't lower room temperature: "They may make you feel cooler, but they don't actually lower the temperature of the room. If the room is already really hot and there's no airflow, a fan will just end up pushing warm air around."
Household appliances like tumble dryers, dishwashers, ovens, and gaming PCs generate extra heat. Angus advises avoiding these during the hottest part of the afternoon, especially in smaller homes or flats.
Should Windows Be Open or Closed?
British Gas engineer Peter Knowles advises: "Keep windows closed during the day. It might feel contradictory, but during the daytime, it's best to keep windows closed to prevent warm air from entering your home. If you've got light-coloured curtains or blinds in heavier fabrics, they can also be effective at blocking heat, if they're kept closed."
Jason Peterkin, CEO and founder of 247 Blinds, echoes the advice: "By closing your windows, which does sound slightly bizarre, and keeping your blinds drawn during the hottest part of the day, it helps prevent warm air and direct sunlight from raising a room's temperature."
Personal Test: Keeping Windows Closed
I tested this method myself. For two days during the peak heat, I closed my windows and drew my blinds from morning onwards, keeping them shut all day. With a cooling tower fan running, my living room was cooler than ever before. However, this method may not work without a fan or other air circulation.
