Right now a heatwave is stuck over Germany like none before this year – and as most of us do not have an AC at home, it strikes us hard. But there are things we can do to mitigate the heat: Ventilation is an important tool to cool down a room, it is environmentally friendly and for free! A few other life hacks can also help to survive the summer heat.
How to cool down a room without an AC
I often see people (such as my neighbors) doing this wrong: With high temperatures during the day, you should not open the windows! Ventilation is key to keep bearable temperatures inside. Open the windows in the evening and make sure to vent your place during the whole night. In the morning, the first thing to do is closing them again and (if available) also closing the blinds to keep the sun out. This way you can lower the temperature inside your flat by several degrees and can keep it that way.
If you open the windows during the day, the hot summer air will enter your home and heat it up. It might feel colder with open windows because it creates a breeze: A breeze makes you feel colder because of the wind chill effect. It makes it easier for your body to conduct heat away from your skin. This is also why ventilators feel so great in the heat. So you will feel a little better, but the increased temperature inside your home will in the long term make it more unbearable inside.
Using an inside and outside thermometer can help you to vent correctly: The windows can be opened right after the outside temperature dropped below the inside temperature. We installed temperature monitoring in our home, so I can show you how ventilation helps us during the current heatwave:
Here is data from an inside and outside temperature sensor in our home during the last 4 days. Please note that the outside temperature in reality is not that high, the sensor is badly placed and always overestimates especially in bright daylight. In reality, we have had temperatures up to 33 °C in the last few days.
But it can nicely be seen how the outside temperature has large variations during the day while the inside only climbs very slowly. This is of course due to the fact that our house has pretty decent insulation, but also because the windows are still closed. Once they are opened (when the outside temperature is low), the inside also cools down over the night: This is when the blue curve drops. By closing the windows again in the morning, it stays on a low level and only climbs again slowly during the day. This way, we manage to keep our home relatively cool despite the heatwave.
More green life hacks to survive the summer heat
Beside proper ventilation, there are a few more things you can do to stay cool:
- Stay hydrated! Cold drinks help the body to lower its temperature, but they should not be too cold to cause a contra reaction.
- Eat cold foods to avoid bringing additional heat into your body. Salads and fruit are great with the heat. I love some refreshing watermelon when I am chilling on the balcony, but ice cream surely also works and tastes even better. Eating hot (and spicy) food will not only bring additional energy and heat into your belly, it will make you feel hotter as well!
- If you want to work out, do so in the morning! I know it is hard to get up early, but it is the best chance you have to enjoy a workout outside. Currently, it gets unbearable here after 9 am, so I am really pushing myself out at 7 to be able to run at all.
- Practice cooling down with contrast showers: The body is more capable of handling heat with more practice. By changing between hot and cold water a couple of times during your shower, you can train this and make your body more efficient and heat tolerant.
- Wear proper clothing! Especially plastic materials are unfortunate because they won’t let sweat out. Natural fibers are much better in the summer heat. In addition, light colors are advantageous especially in the sunshine!
- Put damp towels on your skin or in front of a ventilator: Water evaporating from your skin will take away body heat. This can be as effective as a professional climate system! You can also wet your wrists and ankles every once in a while to cool down your pulse.
What is your best advice to remain cool in the summer?