UK Households Told: Keep Windows Closed This Weekend

Brits are being strongly advised to keep their windows, curtains, and blinds shut this weekend as an unexpected spike in temperatures is on the way. After several weeks of cooler, rainy conditions—which were a win for gardeners but not ideal for outdoor gatherings—temperatures are now set to climb.

Beginning Friday, a short heatwave will sweep across parts of the UK, with southern England likely to experience highs between 24°C and 26°C. While Thursday will remain mild, hotter weather is forecast for Friday and Saturday. According to the Express, the Met Office expects London to hit 24°C on Friday with some clouds, warming further to 25°C on Saturday, before dropping back down to 20°C by Sunday and Monday.

The strong late-May sunshine is making indoor temperatures rise, a real challenge in UK homes that are designed to hold in heat during the colder months. As a result, experts are recommending that households take practical steps to stay cool without running up energy costs.

Energy company OVO Energy warns against the natural urge to open windows when it gets warm. “It might feel right to throw open the windows at the first sign of summer, but that’s not the best way to keep your home cool,” they explained. “The key is to stop hot air from getting inside.” They suggest keeping windows shut during the day, especially those facing south. Curtains and blinds should also be kept closed when sunlight is strongest, particularly if you're not at home. For ventilation, only open windows on the shaded side of your home to prevent heat from entering.

Andy Kerr of BOXT also emphasized that UK homes, built primarily to retain warmth, often struggle to cope with hot weather. While using fans or opening all your windows might seem like good ways to cool down, he cautions that they don’t always work as expected.

“Removing excess heat from homes during the summer can be tricky—most properties are designed to trap warmth,” Kerr said. “Fans and wide-open windows are common go-to solutions, but they may not bring the relief people hope for."

To help people stay cooler as summer arrives, Kerr noted that many popular home-cooling tactics are actually myths. Opening all your windows when it’s hot might seem logical, but it often has the opposite effect by letting in more hot air, which raises the temperature inside.

Instead, he recommends a smarter approach: open windows strategically to create a cross-breeze during the day and fully open them at night to allow cooler air to flow through your home.