There seems to be some disagreement on whether a bathroom door should be left open or closed when it is not in use. This can depend on the situation and location of the bathroom, but personally I think residential bathroom doors should remain open when no one is in there.
The main reason to support this is the fact that you can easily tell when the bathroom is open for use because it is clear that no one is inside. If the door is closed, it can be very hard to tell if someone is inside without knocking or calling out, “Is anyone in there?”. I don't like having to knock on a bathroom door just to find out if someone is in there. It can be even more awkward for the person inside having someone knock on the door and having to yell out, “Yes, someone is in here!”
So why would people close the door when no one is inside? I did a little research and I saw some arguments made that a bathroom is a private room and not something you really want to have on display especially when there is company over. I get where they are coming from, but everyone knows bathrooms exist. It is not something we need to hide away. If there are visitors over such as for a party, they are going to need to know where it is, and they should not have to knock to try to figure out if someone is inside.
I know if I am over at someone's house for a get together and I see the bathroom door closed, I assume someone is in there. I would guess many people would think the same thing and wait until a later time to check back to see if it is open. Then 10-15 minutes go by and you check again and it is still closed. Eventually someone decides to knock on the door or check if someone is in there and it turns out, it was empty the whole time! This kind of situation should not happen which is why bathroom doors should be left open when not in use.
Another argument mentioned is that keeping the door closed keeps unpleasant odors from going to the rest of the house. In rare cases, I could see if you might want to leave the door closed with a fan on for a while, but most of the time, this should not be an issue. If anything, keeping the door open will help ventilate it to help disperse the odor more quickly.
What are your thoughts on this debate of whether a bathroom door should remain open or closed when not in use. Feel free to leave a comment below.