When temperatures rise and our homes heat up, many of us have the same instinct: it's time to open a window. Whilst it might be tempting to leave that window open all day, experts are warning that this could actually be making your home feel hotter.
'In most cases, leaving your window open all day during a heatwave is a mistake. It feels like the obvious thing to do because people want fresh air in the house, but during the hottest part of the day, you’re usually just letting warm air pour straight inside,' says Darren Coates, windows and doors expert at SolarFrame.
But that's not to say you shouldn't have your window open at all. The key here is knowing the perfect time to do it.
When should I open my window?
'Ideally, open windows overnight and in the early morning when outdoor temperatures are at their lowest. In most UK homes, I'd recommend closing windows, blinds and curtains by around 8-9am, or as soon as the temperature outside starts to climb higher than the temperature indoors,' Victoria Robinson, product expert at Hillarys, says.
'Keep blinds and curtains closed throughout the day, particularly in south and west-facing rooms, ideally between 11am and 4pm when the sun is strongest. Then, from around 7-9pm onwards, once temperatures begin to drop, reopen windows and create a cross breeze by opening windows on opposite sides of the home,' she explains.
During the hottest parts of the day, when your windows should stay closed to keep hot air out, there are plenty of other ways to keep cool indoors. You can fill up a hot water bottle with cold water, attempt the 'wet sheet hack' or indulge in an icy foot bath.
Combined with keeping your windows closed during the hottest hours, these simple tricks can help you stay cool throughout the summer.
More heatwave hacks:
- Period homes already had air conditioning – we just forgot how to use it
- 6 tried-and-tested heatwave hacks that actually work – and don't cost a thing
- Loft bedroom too hot to sleep in? 5 fast ways to keep cool during a heatwave
- 4 clever fan tricks that will instantly make your room feel cooler during the heatwave
- Air conditioning isn't just for comfort — it could add £20,000 to your home's value
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