I have also checked what time I showered with the logs of the humidity sensor. It’s a small bathroom so humidity goes from like 30% to 50% in 2-3 minutes and to 60% by the time I’m done showering. Normal humidity here is 25 to 40. So I just put the trigger on 55%, no average or comparing with another room necessary.

My use case was triggering the existing ventilation but I haven’t gotten around to changing the switch for that yet.

I’d like to do the same eventually. I rent though so it would have to be reversible

idk about the US but in australia most ceiling fans plug into standard outlets in the roof, so a smart plug is usually all you need