Water leaks from a plumbing fixture or pipes may go unnoticed for days or even weeks, until you notice a wet spot or water stain on the ceiling below. Once you see that the water is coming through the ceiling, take immediate action before the leak causes any more damage to your house.
Just because you find a leak at a particular point on a ceiling does not mean you necessarily know the point of the leak's origin. Leaking water does not always fall straight down, but can instead run along pipes, floor joists or other surface before falling onto the ceiling below. You must cut a hole in the ceiling and look around with a flashlight to positively identify the origin of the leaking water, or use plumbing access doors such as one found on the wall behind some shower or bathtub faucets.
If your toilet is the origin of the leak, you may see water pooling around the toilet, or the floor around the toilet will feel spongy. If the leak seems to be coming from the toilet's tank, drop food coloring in the tank's water and wait to see where the colored water exits the tank. Tighten loose parts, or replace those that leak even after you have tightened them. The leak may be coming from a loose connection between the base of the toilet and the waste pipe in the floor. You must unseat the toilet, scrape off the old wax ring and inspect the floor flange for damage. Always seat your toilets so they do not rock in any direction; otherwise, the toilet could leak again in the future.
You will see water damage or pooling water in the cabinet below the sink if the sink's drain or pipes are the origin of the leaking water. Tightening the retaining nut on the drain body or the connections between the pipes will eliminate some leaks at the joints. If your pipes do not have plumber's tape on the threads, the pipes may leak even though the connections are tight. If you find it difficult to tell the origin of a leak, dry off the pipes and use a tissue to determine if water comes out of a specific location.
Bathtub and Shower Leaks
If you suspect the shower or bathtub is the origin of the leak, use a bucket to determine if the water supply lines or drainpipes are the cause. By running the faucet but filling up a bucket instead of letting the water go down the drain, you will see if the leaking continues or stops. If the leaking continues, you know the water supply pipes are the cause.