Second Floor Bathroom Soil Stack Leaking - What to Expect for Fix?

[Daniel Galtieri]

This evening I went down in to our basement to find a small puddle of water on the floor, and I noticed some droplets around the main vertical drain pipe (google tells me this is called a soil stack?) from the master bathroom.

At first I thought it might be leaking around the connection, but I was able to take a video with a little endoscope I have and it seems the water is dripping from above the pipe, on to the pipe and then dripping to floor.

Here's a video of what I'm seeing:

View attachment bathroom_leak.mp4

















Couple of other pictures:





I've tested the various water sources from upstairs and I'm pretty sure this is isolated to the master bathroom. E.g. this dripping occurs right after flushing the toilet in the master, and then stops a few minutes later. Flushing the toilet in the other 2nd floor bathroom does not cause this, nor does using any of the faucets on the first floor.


I'll be calling a plumber tomorrow, but I'm mainly looking for some info on what to expect in terms of how this gets fixed. This pipe is squarely in the middle of our house, I have no idea how to access it without tearing apart the house. What is usually the culprit for something like this?

Thanks

 

[CT18]

Could be the connection between the toilet and the flange.

 

[Twowaxhack]

Yep, bad wax seal and or cracked closet flange.

 

[Daniel Galtieri]

So, testing a bit more, it seems that both the shower and the toilet in the master bathroom produce this dripping. Turning on both sinks did not, though. But just running the shower alone definitely produces this as well.