Ventilate Properly in a Heat

When it’s hot outside, airing becomes a bit of a challenge. Simply opening the windows is the obvious thing to do, but it’s not necessarily the right thing to do. We’ll explain how and when it’s best to ventilate in the summer so you have the perfect environment to enjoy online slots Canada.

Airing in summer? Not as easy as some people think! And above all: airing works differently in summer than in winter.

In summer, we are happy about the warm temperatures and long for a maximum of fresh air – and therefore like to leave the windows in the apartment tilted or even wide open all day. Unfortunately, on warm – and even more so on hot – days, this has exactly the opposite effect of what we hope for: The warm and, in summer, very humid air flows into our apartment, spreads out there and makes for stuffy air and a high risk of mold. On warm summer days, we have to rethink how we ventilate:

Ventilate properly in the heat: 4 tips for the summer.

  • To keep the apartment as cool as possible in summer and to let in fresh, cool air when ventilating, it’s best to open the windows very early in the morning (before 8 a.m.) and late in the evening (after 9 p.m.).
  • The basic rule is: if possible, ventilate only at times when the outdoor temperature is lower than the temperature in the apartment.
  • During the day, you should only open the windows wide for a few minutes to provide fresh air.
  • If possible, do not dry laundry indoors in the summer, but outdoors. Here it dries much faster and does not cause even higher humidity. If you don’t have the possibility to hang the laundry outside, you have to ventilate more.
  • The bedroom must be ventilated particularly thoroughly. This is where a particularly large amount of moisture accumulates.



On hot days, it’s best to keep the windows closed during the day so as not to let an unnecessary amount of warm air into the apartment. This is the advice of the consumer advice center and many energy experts. Because once the heat is in the house, you’ve lost. In addition, roller blinds, curtains and shutters are a good protection against strong sunlight.

Of course, the windows should not be closed overnight; in summer, you can sleep well with the windows tilted or even open.


Tilt and shock ventilation are not enough in summer to get enough fresh air into the room. Tilting is to be avoided – no effective air exchange takes place thereby. Cross-ventilation via two windows opposite each other is optimal, because this way a maximum amount of air is exchanged by the draught. When airing in summer, you can leave the doors open in the apartment.



Years ago, weather experts criticized the advice of many experts to keep windows closed during the day. The reason: the lack of oxygen in closed rooms could be dangerous. Their opinion: Even if it is warm outside, drafts are important. It is also recommended cross-ventilation as the best way to provide fresh air.

However, you should bear in mind that if the windows face south and the sun shines directly into the apartment, it quickly gets so hot in the apartment with the windows open that it is almost unbearable.

The healthy compromise is to close the windows and blinds at least during the midday heat. Ultimately, the question of ventilation depends on many factors and is, of course, a matter of judgment. If you leave the windows open on the shady side during the day, you will quickly notice whether the temperature in the apartment is rising or whether the drought is beneficial.


If you ventilate in the evening before going to bed in summer, you should turn off the light so as not to attract insects (especially moths) through the light source. Moths orient themselves at night to the stars and especially to the moon. Man-made light sources irritate the animals and lead them away from their path.

By the way, mosquitoes don’t care much about light – they are not attracted by light, but because it often smells delicious in our homes and because the air inside contains a lot of CO2, which attracts mosquitoes. The only thing that helps here is a fly screen.