Here are some other options, depending on the context:
* En haut: This literally translates to "up there" and is a more informal way of saying "upstairs."
* Au-dessus: This means "above" and can be used to refer to the floor above.
* A l'étage supérieur: This means "on the upper floor" and is a more formal way to say "upstairs."
For example:
* "My bedroom is à l'étage." (My bedroom is upstairs.)
* "Let's go en haut and see the view." (Let's go upstairs and see the view.)
* "The library is au-dessus of the classroom." (The library is above the classroom.)
* "The conference room is à l'étage supérieur." (The conference room is on the upper floor.)