It’s no fun. Believe me. Don’t do it.
Germans do it with sub-zero temperatures outside. People with any sense don’t do it at all.
‘House burping’ is a cold reality in Germany. Americans are warming to it.
The often mandated German practice of airing out homes no matter the season has strained and even ended relationships, but it’s gotten a boost on U.S. social media.
After moving to Berlin from Honolulu, Wyatt Gordon was surprised when his new German roommate marched into his bedroom at 8 a.m. and threw open the windows.
It turned out that his cohabitant, Laura, maintained a strict ventilation regime. Three times a day, at precise times, all the windows in the apartment needed to be opened. It didn’t matter whether it was the dead of winter or a weekend morning, or if Gordon had company. Rules were rules.
Observing Hermann 
This is tired and lame article.. Don’t drink German bier as well. Don’t etc .. Stating one persons strict habit is one thing but comparing it to all Germans is ludicrous.. I’m an expat US living in Europe for over 30 years and I’m the only person that ONLY AIRS OUT OUR HOUSE ONCE in the morning during winter times 5x per week 5-10 minutes max and open the windows during the summer depending on the HEAT temperature for the day.. to capture and compensate for any cooler weather much early.. WHY? Our home is insulated very well and it captures both heat and cool temperatures so there’s no need for fans or ac.