We are presently in the midst of adding an ensuite bathroom which includes a shower. Although the room is located on an outside wall, we are unable to put a window in, as there is an exterior roof line which interferes with placement. We would like to put in a skylght to keep the ensuite bright, as it is so small (approx 5' 6" X 5' 9"). Should we be concerned with moisture building up in the skylight area when showering? Would a fan over the shower or in the exterior wall suffice?
Answer:
I'd put in a fan on each large skylight well wall and make sure it is on whenever there is water running in there and for at least five minutes after showers. These fans should be at least 70 CFM. Without them you'll be replacing drywall around the skylight on a yearly basis and elsewhere in the bathroom every four or five years.