I tried the caveman method to help me sleep cool during a heatwave — here's how it went

When I lived in Sydney, where the summers were scorching and the air conditioning was practically non-existent in residential homes, closing your curtains, blinds and windows to block out the glare of the hot sun was practically mandatory.

Like many things, TikTok has taken this nugget of good sense and spun it into a sleep hack with a fancy new name — the 'caveman method'. The caveman method is essentially a term to describe keeping your bedroom cool and dark like a cave, with little airflow entering from outside.

Where I now live in the UK summers can be warm, but it’s rare for us to have a long run of uncomfortably hot nights like we’ve experienced recently. So keeping the blinds and curtains closed hasn’t really been necessary.

But now, in the grips of a long-running heatwave that is wreaking havoc on my sleep, I decided to give the ‘caveman method’ another go to see how much of an impact it could have. Here’s what happened…

What is the caveman method?

If you’ve ever walked into a cave on a hot summer’s day you’ll have noticed that the temperature drop is significant — and that’s what you’re trying to emulate with the caveman method.

When the outside temperatures are set to exceed the indoor temperatures, it’s time to close the curtains, blinds and windows to create a cool haven.

So, while you might be tempted to open a window to capture a passing breeze when the temperatures soar, you should do the opposite.

Shut your bedroom window in the morning to capture the cold night air and keep your curtains closed all day to prevent your room from baking in the sun. Et voila! It’s cool like a cave.

What happened when I tried the caveman method

I have a fairly high tolerance to sleeping well in the heat, but once it started to impact my kids' sleep I knew it was time to act. Enter: the caveman method.

I tried out the caveman method on a beautifully sunny day. But with temperatures set to hit 94° F (34 °C) later that day, I decided not to open the curtains. It also still felt relatively cool in our bedrooms so I closed the windows to trap in that nighttime air.

Unless you're out of the house, the strangest thing about the caveman method is the dim lighting.

Despite the bright daylight outside, I was working from home in, well, a cave of darkness. I turned on a lamp to join a meeting while my colleagues sat in t-shirts to a backdrop of sunshine.

However, around lunchtime, when my house usually starts to swelter, I still felt cool and comfortable. The biggest impact was stepping into my boys' bedroom at bedtime.

They usually get the glare of the evening sun, which makes their room uncomfortably hot. This time? It felt significantly cooler and they were able to fall asleep quickly — winner.

My own bedroom also felt markedly cooler than normal. While I usually like to sleep with the window wide open, I kept it closed so I didn't disturb the cool haven I had created. I fell asleep as quickly as normal and slept through the night.

Will I try the caveman method again? 100% yes (I'm still using it.)

How to cool your room with the caveman method

1. Close your bedroom window in the morning

It’s easier to keep a room cool than actively cooling a room that’s become blisteringly hot throughout the day.

If you’re expecting it to be a hot day, close your windows in the morning and don’t open your curtains or blinds.

Closing the windows first thing in the morning keeps the cool night air locked in your room and prevents the hot air from outside entering.

2. Block out the glare of the sun

Keep your curtains closed in the morning to prevent the glare of the direct sun turning your bedroom into a sauna.

Blocking out the glare of the sun is a crucial step in the caveman method. However, if your curtains are thin or your blinds allow some sunlight through, you won’t get the same cooling effect.

If that's the case, I'd recommend picking up a pair of blackout curtains in the Prime Day sleep deals. (My pick would be this pair of portable blackout curtains which are 34% off at Amazon.)

3. Open the windows when the temperatures drop

If you’re lucky enough for the temperatures to drop once the sun has gone down, that’s when you should open your bedroom window.

Opening your bedroom window allows the cool air to permeate your bedroom — bliss. Temperatures not budging? I have a few other tricks up my sleeve…

3 other hacks swear by for cooler sleep this summer

1. Create your own aircon

I’m not blessed with air conditioning but there is a hack I swear by that gives (almost) the same cooling benefit.

Placing an ice pack in front of a fan means that the air that circulates the room is chilled, helping to lower the room’s temperature.

2. Take a warm shower before bed

It's stiflingly hot, you've worked up a sweat just by walking up the stairs, you can't wait to jump into a... warm shower? It feels counterintuitive but taking a warm bath or shower can actually help cool you down and fall asleep faster.

Before we fall sleep our core body temperature drops. Our core temperature also cools when we get out of a warm bath or shower, signalling to our brains and bodies that it's time for shut-eye.

3. Switch from a duvet to a top sheet

Switching to breathable, cooling bed sheets is the first thing I do when the temperatures start to rise.

But when nighttime temperatures barely drop, I switch my duvet entirely for a breathable top sheet. That way you get the benefit of feeling snuggly but without any of the added heat.