This clever sheet cooling hack 'turns an underperforming setup into something surprisingly effective' – it’s perfect for homes without built-in cooling

Struggling to stay cool this summer? With temperatures across the country hitting record highs, it's no surprise. And, without built-in cooling like air conditioning, you might be finding yourself turning to more unconventional tips and tricks to keep your home comfortable and cool.

One of these that our pros recommend is so simple, yet so effective: using a bedsheet to separate your home into smaller sections, rather than trying to cool the entire space.

Here, HVAC experts explain why this sheet cooling hack works to keep a home cool in a heatwave, with advice on how to try it in your own home.

What is the sheet cooling hack?

As Michael Zohouri, founder of Pyramid Eco, explains, the sheet cooling hack involves hanging a sheet across a doorway, sectioning off a smaller space so your portable AC or best fan only has to cool one room, not the entire home.

'Smaller spaces reach a comfortable temperature faster and use far less energy,' he says.

Therefore, this clever home remedy to stay cool is also an effective way to cut energy bills, too.

Why does the sheet cooling hack work?

As Danny Pen, president at New Era Plumbing & HVAC, explains, 'Cooling an entire apartment with a single portable unit spreads the cool air too thin.' Therefore, by hanging a sheet over a doorway, you're shrinking the space you're asking your unit to cool, helping to cool down a bedroom fast, or cool down a living room.

Chuck Woosley, general manager of The Bee, agrees, adding, 'This hack works because it helps direct and retain the cool air produced by a portable AC unit, essentially creating a more concentrated cooling zone.

'By hanging a lightweight sheet around the unit or the sleeping area, you're limiting how far the cool air has to travel and reducing how much escapes into the rest of the home. Just be sure the setup doesn’t block air intake for your fan or AC or pose a fire risk.'

Additionally, says Josh Mitchell, HVAC technician and founder of Air Conditioner Lab, heat always tries to move from a warmer area to a cooler one.

'By hanging a thick sheet [such as a thick washed cotton duvet cover from Walmart], you're adding an extra barrier that helps reduce that transfer,' he explains. 'It keeps the cool air where you want it, and slows down how fast warm air can creep in from other parts of the house.'

For that reason, this hack is particularly effective if you're in need of more unusual methods for staying cool at home, without the option of simply using air conditioning.

Danny concludes, 'This isn’t a permanent fix, but it’s tactical, and works best in extreme heat, at night when you’re trying to sleep, or if you’re working from one room all day. It turns an underperforming setup into something surprisingly effective.'

How to do the sheet cooling hack

If you want to try this sheet cooling hack in your own home, here's how:

1. Choose the room you want to cool: This is likely to be where you sleep or work.
2. Pick your sheet: Then, pick your sheet. Michael advises, 'Choose a lightweight cotton sheet or curtain that is large enough to span the entire doorway and reach close to the floor. This helps create a physical barrier to contain the cooled air within one space.' You can also use a blackout curtain if you have one, which Josh says will work best, such as the bestselling Mainstays Solid Blackout Curtain Panel Pair available at Walmart.
3. Attach it to your doorway: Then, hang your chosen sheet, curtain, or blanket over your doorway, making sure it touches the floor and overlaps with the edges of the doorframe. 'Secure it with thumbtacks, command hooks, or tape along the top and sides to block airflow,' says Josh. Alternatively, you can use a tension rod, painter's tape [such as the Duck Brand Clean Release Painter's Tape available at Amazon], velcro, or magnets.' If the sheet tends to lift at the bottom, secure it with a light object like a draft stopper or tuck it under a rug,' adds Michael.
4. Run your portable AC or best fan: Finally, you're ready to run your portable AC or fan inside the room. 'Make sure the AC hose is vented out the window properly,' advises Josh. 'Shut the door if you can, or let the sheet take its place if there's no door. Cool the room for one to two hours before use, then run the AC as needed.'

Importantly, and helpfully, you don't need to run your portable AC nonstop. 'Using a timer or setting it to cool the room before you get home is a smart way to save electricity,' adds Josh.

You can also rearrange a room to make it cooler, which works well in conjunction with the sheet cooling hack.

What are the drawbacks of this sheet cooling hack

As with most, if not all, tips for handling extreme heat at home, this method is not without its drawbacks.

Josh begins, 'The most obvious one is that you're sealing off a room. You'll have to push the sheet aside or unhook it if you want to move in and out, which can be inconvenient. A sheet hanging in the middle of a home also doesn't look great if you have visitors.'

To Michael, the biggest issue here is airflow. He explains, 'If you block off the space completely, fresh air circulation can be limited. And, if your portable unit needs to vent warm air through another room, you'll need to make sure that hot air doesn't leak back in.'

As Danny adds, this limited airflow can also lead to damp bedding or clammy air, which, over a prolonged period of time, could lead to flourishing mold and mildew.

Additionally, and obviously, Josh says, as this method only cools one room, the rest of your home stays warm.

But, to Benjamin Uscilla, owner of Evergreen Heating and Cooling, this hack will work, and he doesn't see any drawbacks worth noting. 'I have no problem recommending it either,' he says. 'It can work in a very simple form. You're simply creating a defined space for that cool air to stay.'

Really, there's only one way to find out if this hack works for your home – grab a bedsheet and give it a whirl. If you do give it a go, we'd love to hear about it in the comments below!

What to shop

All prices were correct at the time of publication.

Meet our experts

Michael Zohouri

Michael is the founder of Pyramid Eco, a company which focuses on energy efficiency and healthier indoor environments. He has extensive hands-on experience addressing ventilation, insulation, and air quality issues in homes of all sizes.

Josh Mitchell

Air Conditioner Lab was founded by HVAC and tech enthusiast Josh in 2014, as a way for him to document his findings on home air conditioners and effective and unusual cooling methods, like the sheet cooling hack.

'For anyone without central AC relying on portable units, I recommend the sheet method,' says Josh. 'It's a practical and low-cost solution that improves the efficiency of your cooling efforts. It's not a long-term fix for whole-house comfort, but it's a great way to make one room feel better fast. I've seen it help people sleep better on hot nights or stay comfortable while working from home.'

Similarly, have you heard of the 'caveman cooling method'?