Condensation on all windows

One and a half years ago, we built ourselves a wooden house as a KFW-60 house. However, starting from this year's cold season, we have been struggling with moisture on our windows day by day. Every morning, before leaving the house, we ventilate all rooms completely for about 15 minutes – but even that is not enough. Could it possibly be due to the poor vacuum of our double-glass windows? During the installation of the windows, they had to be reset by the house-building company, which I will not name here, because they were installed incorrectly. Could the vacuum have been compromised during these works? It should be mentioned in advance that we have a heating setback from 11:30 PM to 5:00 AM and heat the entire house with underfloor heating. Can someone help me here before I possibly have to involve an expert?!

Kind regards Marc

Condensation is actually a sign of too high humidity in the room, which settles as condensate at the weakest points, and these are usually the edge seals of the window panes. This is especially noticeable in the cold winter months and especially at sub-zero temperatures. What you have also sounds a bit like a ventilation problem. Is there no controlled apartment ventilation in the house? Ventilating once a day for 15 minutes is definitely not enough! You should do this for at least 15 minutes in the morning and then again in the evening. Regards Rusti