Cover windows with tin foil and homes should feel cooler in hot weather

Cover windows with tin foil and homes should feel cooler in hot weather Some parts of the country are expected to heat up from Monday, with 30°C highs A science expert has said there's a specific reason why homes in the UK feel "insanely hot" - and has shared the unusual method people could use to stop it. The UK is preparing for its third heatwave of the year, with certain areas expected to warm up from Monday, July 6, with temperatures soaring to 30°C. Last week saw multiple June temperature records broken as a historic heatwave swept through much of the UK. Cambridge professor and BBC regular Hannah Fry has shared another piece of "slightly impractical" science that might help Brits get ahead of the approaching heat. Referred to as the greenhouse effect, sunlight passing through glass window panes warms up a space, she explained to her 2.2 million followers. These light waves can pass through the glass easily, but it's the light attempting to exit that creates the issue. Once indoors, these waves of thermal energy are essentially "trapped", resulting in the all-too-familiar feeling of unbearable warmth, reports the Express. Hannah said: "As soon as [the light waves] get inside, they bounce around and they change to much shorter wavelengths - and they're then trapped. "It's sort of like you've got this one-way filter to the outside, letting in loads of energy but not letting any of it escape, which is why your room ends up heating up." Appearing soon on BBC's Celebrity Traitors, Hannah reckons most people will be familiar with the curtain trick for shielding homes from excessive heat when temperatures rise. However, there's a better - though slightly unusual - way to block heat during the next scorching spell. Hannah said: "A lot of people, myself included, will close the curtains on a warm day, but it's like you're sort of trying to stop the invaders once they're already inside the room. It kind of helps a little, but nowhere near as well as hanging a sheet on the outside of your window. "If you really want to minimise the amount of extra energy that is coming in when it's absolutely boiling outside, you should get some tinfoil and basically copy what they do in space. Get some tinfoil and then attach it to the outside of your window." Does the tin foil trick work? Tinfoil acts as a reflective surface for infrared radiation. Aluminium foil deflects up to 90% of the sun's radiant heat, redirecting solar energy back outdoors before it penetrates the room. If you attempt this technique during the next heatwave, ensure the foil is attached to the outside of the glass. Placing foil on the inside still allows heat to pass through the window pane, but it becomes trapped in an even more dangerous location. Thermal energy becomes stuck between the glass and the foil. This concentrated heat can cause the window to become excessively hot, potentially leading to cracks or complete breakage.