You don't need air conditioning to make a room livable in a heatwave — you need to stop heat coming in, let it out at the right time, and help your body cool itself. Here are 15 methods, ordered roughly from most to least impactful, plus where cheap cooling gear fits when the free tricks aren't enough.
Stop heat getting in
1. Shade windows from the outside. Roller shutters, external blinds, or awnings on the south- and west-facing sides block heat before it passes through the glass — the highest-impact move you can make.
2. Close curtains on the sunny side. If you can't shade outside, light-colored or thermal/blackout curtains kept closed all day are the next best thing. Reflective panels help most.
3. Shade each side before the sun hits it. East rooms heat in the morning, west rooms in the late afternoon. Pre-empt the sun rather than reacting to it.
4. Close interior doors to hot rooms. Contain the heat in the sunny side of the home so it doesn't spread to the room you actually use.
Let heat out at the right time
5. Ventilate only when it's cooler outside. Open windows late at night and at dawn; close them once the outside air climbs above your indoor temperature.
6. Create a cross-breeze. Open windows on opposite sides of the home at night to flush out the day's heat quickly.
7. Exhaust warm air with a fan. A fan facing out of a window at night pushes warm air out and draws cooler air in from the other side.
8. Turn off heat sources. Lights, the oven, and idle electronics all add warmth. Cook with the stove or microwave instead of the oven, and switch off what you're not using.
Move air and cool your body
9. Point a fan across your skin. Moving air speeds up sweat evaporation, making you feel several degrees cooler even though the air temperature doesn't change. See which fans are in stock near you.
10. Add ice to your fan. A bowl of ice or a frozen water bottle in front of the airflow gives a small, cheap chill boost.
11. Cool your pulse points. Cool water on your wrists, forearms, or the back of your neck cools you faster than you'd expect.
12. Dress and sleep light. Loose cotton, lightweight bedding, and a cooling mattress topper all reduce how hot you feel.
13. Take a lukewarm shower. Lukewarm — not ice-cold — lowers skin temperature without triggering a rebound warm-up afterward.
14. Stay hydrated. Your body's sweat-based cooling only works if you keep drinking water through the day.
When you want active cooling
15. Add an air cooler or mobile AC. When shading and airflow aren't enough — especially in a top-floor flat — an evaporative air cooler or a mobile air conditioner is the fastest upgrade. Both sell out quickly in a heatwave, so check live stock before you set out, and set a restock alert if everything nearby is sold out.
Most of these methods are free and worth doing by habit. When you do decide to buy, the trick is timing: the cheapest fans and coolers vanish within hours of a heatwave being announced, so buy early or get notified the moment stock returns.