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How to stay cool indoors without air conditioning

Once the building is doing what it can, the rest is about you, the people around you, and the animals who cannot tell you they are struggling.

You can do everything right with your windows and still be miserable. Body temperature, hydration, and the small habits of a hot week matter as much as the building does, and they are the part you control minute to minute.

Cooling a body is not the same as cooling a room

Your body sheds heat mainly by evaporating sweat. That is why moving air feels cooler even when the air temperature has not changed, and why humidity makes the same temperature feel far worse: when the air is already saturated, sweat has nowhere to go.

This is the whole reason a fan helps a person but not an empty room. Point it at yourself and you speed up evaporation from your skin. Leave it running in an empty room and you have just added a small heater. See how to cool your body down.

Eat and drink for the week, not the moment

Hydration during a heatwave is a steady, boring discipline rather than a rescue action. Sipping water through the day works. Drinking a litre when you already feel unwell is catching up too late. Heavy meals and alcohol both add to the load your body is carrying. See what to drink and eat.

The ones who cannot tell you

Pets overheat faster than people and have far fewer ways to shed heat. Dogs cannot sweat through their skin. Cats will find the coolest tile in the flat but can still get into trouble. Plants wilt visibly and are easy to over-correct with midday watering that mostly evaporates. See keeping pets safe in the heat and watering plants and floors.

Watch the people around you

Older neighbours, very young children, anyone on medication that affects temperature regulation or hydration, and anyone living alone are all at higher risk than a healthy adult. A heatwave is a good week to knock on a door.

Safety first

These are comfort measures, not medical advice. Confusion, a headache that will not shift, a stopped ability to sweat, or a body temperature that keeps climbing are emergencies. Follow your local health agency’s guidance and seek help.

In this guide

Common questions

Is it bad to point a fan directly at yourself?
A fan aimed straight at your face for hours can dry your eyes and airways and can leave you stiff. Oscillating mode, or aiming it slightly past you, gives you the same evaporative cooling without those side effects.
Are ice-cold drinks the best way to cool down?
Cool drinks are better than ice-cold ones. Very cold liquids can cause stomach cramps when your body is already overheated, and they do less for your core temperature than steady sipping of cool water through the day.
Does putting a bowl of water in the room help?
Only when air is moving over it. Evaporation is what cools, and evaporation needs airflow. A bowl of water in still air does almost nothing, and in an already humid room it can make things feel worse.
How do I know if my pet is overheating?
Heavy panting that does not settle, drooling, vomiting, unsteadiness, or collapse are all warning signs. Move them somewhere cool, offer water, and call a vet. Never leave an animal in a parked car, even briefly.

These guides are informational and are not medical advice. If heat is making you unwell, follow your local health agency’s guidance.

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