where I used to assume there was some universal magic number.
“Exactly 17 minutes.”
Apparently, it isn’t that simple.
How long you need depends on the bathroom, the fan, the size of the room, how hot and long your shower was, and how effectively the bathroom is ventilated.
A commonly suggested approach is to keep the fan running for a while after the shower—often around 15 to 20 minutes—but the important idea is not the exact minute on the clock.
It’s giving the moisture time to clear.
If your bathroom
