What to Do When There is a Bathroom Ceiling Leak
If the ceiling's going to leak in any finished room of the house, it might as well be the bathroom. After all, this is one area that's used to water. But enough of this foolish positive thinking. Your ceiling has sprung a leak and that's never a good thing. So now what do you do? First, you identifyPosted — Updated
Not to insult your intelligence or suggest alarmist behavior, but sometimes what appears to be a bathroom ceiling leak is really a big condensation problem. If you're finding droplets of water in more than one place and you don't have—or don't use—a bathroom vent fan (that noisy thing that alerts everyone to enter the bathroom with caution), you might have too much moisture that's simply collecting on the ceiling surface. The water or water marks might even be somewhat discolored, and that's just due to the fact that no sane person regularly cleans their ceiling (so you're off the hook there).
Prolonged condensation problems may result in peeling paint and/or mold growth, but they're less likely to penetrate upward into the ceiling material. If the drywall seems solid in the affected area and there's no circular or ring-like water mark on the ceiling around the center of the "leak," try wiping the ceiling to remove all traces of water. Then, open a window or run your vent fan during and after your showers for several days to see if the water comes back. No? You're in luck. It's probably just condensation.
If your ceiling failed the condensation test, it's time to consider possible causes of a true leak. Since you probably don't live in a grotto, there's no chance the ceiling itself is leaking. What about plumbing pipes above the ceiling surface? These could be supply pipes, which could be leaking or possibly have their own serious condensation problems, or they could be drain pipes, in which case the water is not something you want to have dripping onto you (it's on its way to the sewer).
Is there another bathroom above this one? If so, it could have a leaky toilet, sink, shower or tub. Check the location of each fixture above to see if the leak matches up. Water from a tub or shower could come from a leaky drain, supply pipe or faucet, or even from a breach in the shower/tub enclosure, such as cracked grout in the wall tile or a failed caulk joint. You can test this by not using the shower/tub for a few days to see if the leak stops. A leaky toilet will drip water whether the fixture is used or not. A leaky sink drain will reveal itself on the floor below or inside the vanity cabinet. However, keep in mind that leaking water can travel along the top of the ceiling before it actually drips through to the bathroom below, so the source of any leak might not match up with the stains on your ceiling.