Not necessarily. If the bathroom is in a lower floor or the basement, it's easier to vent the fan through a side wall. In such cases, a wall-mount fan usually makes more sense than a ceiling-mount.

Well, you can't! You'd often blow air from one bathroom into the other, and local building inspectors wouldn't approve it. But while you can't have two fans with one vent, you can make one fan and ...

Dewy Studios said, "I don't even get a fan. Just a window." and Brandon replied, "That works too!" How Often Should You Clean Your Bathroom Vent? You may hear it referred to as a bathroom vent ...