Question about a leak

[ddniners15]

I’m a homeowner and cannot figure out the source of a leak and was looking for some general guidance. Last night, water was leaking through my kitchen ceiling directly underneath the toilet in our master bathroom. I opened up the ceiling and could see water dripping through the floorboard from the supply line. I then opened up a portion of the wall behind the upstairs toilet and can see the same line, but no evidence of leakage outside of some tiny damp spots where the line goes though the floor. This line to the toilet also tees off to supply the cold water for the guest bathroom sink on the other side of the wall. I had just put in a new sink a few days ago but the only thing I changed was putting on new shut-off valves. I had no leaks with the valves and verified no water was leaking down the line inside the wall.

I’ve had pinhole leaks in that line before, so I assumed I had the same somewhere where the line goes through the upstairs floor. I shut the water off overnight, the leak stopped, and a plumber came out today. Turned the water back on, let it go for a few hours and no leaks anywhere. I can’t figure out what happened or where the water came from, and the plumber didn’t know either.

Any advice /thoughts would be greatly appreciated. Thank you.

 

[moonlight]

Are you sure its from the supply? Could it be the overflow from the toilet?

 

[ddniners15]

Are you sure its from the supply? Could it be the overflow from the toilet?

Good question. I hadn’t considered that. It just seemed so localized to the supply line, I didn’t see any evidence of any other water source, and it stopped once I shut the water supply off.
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Good question. I hadn’t considered that. It just seemed so localized to the supply line, I didn’t see any evidence of any other water source, and it stopped once I shut the water supply off.

I’ve also flushed the toilet numerous times since with no issues