You've been using your fan all wrong — this surprising hack helps you cool down a room faster

Let’s face it, we Brits aren’t exactly made for 30°C + temperatures. So, when the country is gripped by a heatwave, we instinctively reach for a fan to try and keep our homes cool. But it turns out we may have been using them all wrong and TikTok has something to say about it.

Rather than pointing the fan directly at yourself and hoping for the best, users on the platform are flipping the script – quite literally – by positioning their fans to face out of their bedroom windows instead.

The idea is to push hot air outside of the room, rather than just swirling it around inside. And while it might sound counterintuitive, the results are surprisingly effective. Below, we asked experts why and how this social media 'hack' actually works.

The clever fan 'hack' shared on Tik Tok

This clever fan trick started gaining traction when home content creators –– such as @alexthecleaner (featured above) –– began sharing reels showing how they use a standard desk fan in a way most of us had never considered. Instead of pointing it into the room, they positioned the fan so it blows out of their bedroom window.

Naturally, the comments came flooding in, with many viewers admitting they’d never thought to use a fan this way. One follower wrote, “This feels wrong, but it works so well,” while another chimed in with, “Can you really call physics a ‘hack’?”

So, how does this reverse-fan method actually work? We asked the experts…

How and why does it work?

To understand what’s really going on, we asked Nicholas Auckland at Trade Radiators and Katie Lilywhite, air treatment expert at AO.com, to explain the science.

“Positioning a fan to face out of an open window works like an exhaust fan,” explains Nicholas. “It creates negative pressure inside the room, which actively pushes the warm, stale air out. As this air is removed, cooler, fresher air from outside is drawn in to replace it. You're essentially creating a ventilation system.”

Katie agrees, describing the process as “reverse ventilation.” “When you point your fan facing outwards through a window, you’re basically creating an exhaust system. Your fan pulls the warmer air from inside your room and pushes it outside, which can be surprisingly effective at lowering your room’s temperature – especially when it feels stuffy and stagnant during a muggy night.”

So how does this compare to using a fan the more traditional way?

“Pointing a fan at yourself doesn't actually lower the room's temperature at all,” Nicholas explains. “It creates a wind chill effect, which helps you feel cooler by evaporating sweat from your skin. But if you’re not in the direct path of the breeze, you won’t feel much benefit, as the fan isn’t cooling the air, it’s just moving it around.”

Katie adds: “You’ll enjoy a breeze, of course, but it doesn’t reach the root of the problem – the heat stuck in your room. Facing your fan outside can actually remove this heat and help create a genuinely cooler environment, especially in the early mornings or late evenings.”

Nicholas Auckland

Nicholas Auckland is a heating and energy expert with almost 20 years of experience in the industry, as well as the Managing Director of Trade Radiators.

Katie Lilywhite

Katie is one of the many experts at AO.com, covering a multitude of appliances including air quality products, health and beauty and homes and gardens.

When to try it

If you're tempted to try this hack at home, timing is everything. “This technique works best in the late evening or early morning when the outside air is noticeably cooler than the air inside,” explains Nicholas. “If the air outside is warmer or the same temperature, you're just drawing in more heat, which makes the whole thing pointless.”

Katie expands on this: “You’ll want to run your fan at these times before the sun ramps the heat up. However, you’ll struggle to pull off this trick during hot afternoons. If the temperature is hotter outdoors than it is in your home, then all you’ll do is pull hotter air in, making things worse.”

To get the most out of the method, both experts recommend creating a cross-breeze – a simple form of natural ventilation. “Open another window or door on the opposite side of the house,” suggests Nicholas. “This helps pull cooler air through the space and speeds up the cooling process. Of course, not all homes will allow for this depending on layout, but it can make a noticeable difference.”

During the peak heat of the day, the advice is simple: block the heat out. “Keep windows and curtains closed if the air outside is hotter,” Nicholas advises. “Blackout blinds are ideal. Use a fan to circulate air inside. Just make sure it’s facing you to create that cooling breeze effect.”

Shop the best fans for keeping cool

With energy costs on the rise and full-blown home air conditioning still a rarity in UK households, it’s easy to see why this clever fan trick is catching on. Most of us already have a portable fan on standby for summer, but it might be time to rethink how you’re using it. Still on the hunt for a reliable model? We’ve rounded up some of the best fans for cooling your home this summer:

Still too hot to sleep? Try this easy DIY air conditioning trick for an affordable way to cool down a room fast.