The average person spends like 3-5 hours in front of a screen for entertainment only, I'm fairly sure spending 30s here and there to open windows is in the realm of possibilities
Average person spends 3-5 hours in front of a screen, so this task taking less than 3 hours is reasonable to do.
Something about that rubs me the wrong way. Doesn't it matter that the task is menial and doesn't seem all that effectual?
It's actually quite meaningless.
Yes, water vapor in the air causes mold, but here is the thing: the water only sticks to cold walls.
It is the combination of a cold wall plus water in the air that is the problem. Ventilation alone cannot make your wall warmer, in fact, excessive ventilation may cool your walls down even faster. As expensive as it might sound, the only reliable solution is to properly insulate the wall and keep it warm.
I hear you, but the idea of shock ventilation is to swap out the air without cooling the walls.
I'm renting an apartment in Germany in a building from around 1900 and I do have a clause requiring me to open my windows at least once a day for at least 5 minutes. Not sure that if it's legally enforceable, but if clauses about keeping some minimum temperature indoors are binding (judging from the fact that the government made them explicitly invalid at some point in 2022 when the country got left on thin ice after Russian gas got shut off), then I wouldn't be surprised if that one were binding as well.
Afair the rules about minimum temperatures that got loosened are all about requiring the landlord to provide sufficient heating that the home is livable (it must be possible to heat the home to 20°C during the day and 18°C at night with the provided heating). The tenant is only required to not damage the apartment by letting mold grow or pipes freeze.
I've never assumed anyone to actually do all of this excess ventilation, though...I've always been too lazy to "open all windows three times a day for five minutes each" (where the heck do people find the time to do that each and every day?), and the "solution" of just opening the window a little over a long period is so obviously expensive in terms of heating costs that I rather keep most windows closed most of the time (except bathroom after showers for obvious reasons).