Hello
I just got around this topic:
https://support.tado.com/en/articles/3387308-how-does-the-open-window-detection-skill-work
The main thing is that the tado thermostat uses sudden changes in temperature or humidity to detect if a window is open and switches off for a while to save energy.
Oke this can be replicated in HA whit automation.
I’m Thinking if the temperature drops ex. 5° in 5 minutes stop the heating for 10 minutes in the specific room.
After that, it will start back automatically again.
What do you think about this automation, eventual do you have some reference points, 3° instead of 5° or 2 minutes instead of 5 minutes.