During the rain today, I noticed a dripping sound behind the wall of the main floor washroom today. It sounds like its coming from right behind the toilet. Right behind the toilet, the main plumbing stack runs vertically through that wall, into the attic, and straight out of the roof.
This is what it looked like when the walls were opened up:
The main stack is the black pipe just to the right of the window in the photo.
The roof vent looks similar to this:
The dripping sound stopped right after the rain stopped. I don't see signs of water on the ceiling of the bathroom, the wall behind the toilet, or the ceiling of the room below it in the basement. I also peeked inside the attic, and didn't see any signs of water, but it was hard to tell, as the blown in attic insulation goes almost right up to the roof decking in that area.
Does anyone have an idea of what could be causing that sound? Perhaps some rain went into the stack? Although I'm not sure that would cause such a dripping sound since the pipe runs straight up and down. Maybe where that "T" is the inside of the pipe has some corners that water could drip from?
Maybe go onto the roof with a garden hose and spray directly into the stack vent to see if you can produce the same sound.
Then spray around the stack vent to see if you can produce the same sound.
I'be heard stuff like this in the past too: also couldn't figure it out and it still happens over a decade living in my house... Here's some guesses/ eliminations:
A) vent boot could have gap/cracking due to age causing drip
B) doubt it's from your faucets or anything that holds pressure such as the pipes where water passes as if there's a leak in those areas, it'll be constant dripping
C) doubt it's the toilet plumbing as that sound will occur when you use the toilet (or all the time if it's leaking/not flushing properly causing water to keep refilling) and not just when it rains
And my strongest hunch--
D) the water drips straight from the roof vent hole, and something got stuck in the pipe below and water drips are heard whether echo or the water directly hit that debris on the pipe (eg I've had birds nest or debris or whatever stuck in the vent and had to power wash/flush it out... I knew it was related to the vent coz I could hear gurgling sounds on the other fixtures in the same bathroom when that occurred eg my bathtub drain would gurgle when it didn't before)
Either way as another poster said , my hunch has to do with outer vent area (vent boot or vent itself blocked or piping heading down blocked a bit ). I doubt is a leak in the toilet plumbing nor faucet plumbing... That's my own past experience
Let us know eventually what you see... Good luck!
PS how did you get the picture of the innards of your bathroom? I guess you remodeled the bathroom? If recent remodel I'd be more concerned about loose fitting , if long time ago, then I'd suspect the ones I've mentioned already...
SleepAddict wrote: ↑
During the rain today, I noticed a dripping sound behind the wall of the main floor washroom today. It sounds like its coming from right behind the toilet. Right behind the toilet, the main plumbing stack runs vertically through that wall, into the attic, and straight out of the roof.
This is what it looked like when the walls were opened up:
20190724_210932.jpg
The main stack is the black pipe just to the right of the window in the photo.
The roof vent looks similar to this:
The dripping sound stopped right after the rain stopped. I don't see signs of water on the ceiling of the bathroom, the wall behind the toilet, or the ceiling of the room below it in the basement. I also peeked inside the attic, and didn't see any signs of water, but it was hard to tell, as the blown in attic insulation goes almost right up to the roof decking in that area.
Does anyone have an idea of what could be causing that sound? Perhaps some rain went into the stack? Although I'm not sure that would cause such a dripping sound since the pipe runs straight up and down. Maybe where that "T" is the inside of the pipe has some corners that water could drip from?
I'm really hoping its not a leak...
Unless it was replaced, it looks like you have a cast iron plumbing stack based on the photo (furthest left pipe in the wall cavity that has rings around it). Cast iron is often irregular and "bumpy", so the boot that goes around it on the roof doesn't always fit tightly and can result in a slow drip leak around the collar during heavy rain
I had the same issue and ended up using some commercial grade polyurethane sealant around the pipe and the collar, and that fixed it up for me.
OP - during rain/heavy rain, you should poke your head up into your attic and look at where the plumbing stack terminates through the roof. I bet you'll have a slow drip occurring there.
Images
Last edited by jacquesstrap on Jul 14th, 2021 10:48 am, edited 1 time in total.
You did a lot of ripping out chasing this problem down, at this point you're half way between buttoning it back up or taking the plunge and renovating the bathroom.
Could have been a drain pipe with a pin hole leak but obviously you would have seen that by green on the copper pipe along with some kind of water. Yours look water tight all round.
“Laughter is timeless, imagination has no age.....and dreams are forever.”
Ballroomblitz1 wrote: ↑
You did a lot of ripping out chasing this problem down, at this point you're half way between buttoning it back up or taking the plunge and renovating the bathroom.
Could have been a drain pipe with a pin hole leak but obviously you would have seen that by green on the copper pipe along with some kind of water. Yours look water tight all round.
I think that's a photo from a previous renovation, and not the OP destroying his bathroom after hearing the dripping noise.
Yes, that photo was from a few years ago when the bathroom was remodelled. It's now finished so I can't see behind that wall.
I'll try going up onto the roof and inspecting the flashing around the vent, as you guys suggest. It certainly seems plausible water is coming in around the vent pipe.
I get a dripping sound in my place as well. For me, it's the vent for my furnace; sounds like it's nowhere near where it actually is, but that pipe ends in a flat bottom, and water sometimes drips internal to the pipe and hits the bottom plate.
Just a suggestion, maybe search to see if another pipe relatively closeby is the issue.
One who is offended by truth, has no place among those who seek wisdom.
Yes, that photo was from a few years ago when the bathroom was remodelled. It's now finished so I can't see behind that wall.
I'll try going up onto the roof and inspecting the flashing around the vent, as you guys suggest. It certainly seems plausible water is coming in around the vent pipe.
Try using a binocular first, I am old so I don't dare go up roofs... I'd rather buy a drone if need be... ☺︎
Heh, I would have used a drone if I had one. Luckily its a bungalow with a shallow roof slope so it wasn't too difficult to get up there.
The cast iron pipe is indeed a bit "bumpy" on the outside, but the rubber gasket around the flashing seems okay I think? It seems fairly pliable. I did notice a few tiny cracks though, do you think these could be enough for water to get in?
I tried spraying water directly into the pipe with the garden hose, but that didn't reproduce the dripping sound.
According to the previous owner the roof is about 12 years old now. I'd assume that the gaskets/flashing were replaced at that time.
SleepAddict wrote: ↑
Heh, I would have used a drone if I had one. Luckily its a bungalow with a shallow roof slope so it wasn't too difficult to get up there.
The cast iron pipe is indeed a bit "bumpy" on the outside, but the rubber gasket around the flashing seems okay I think? It seems fairly pliable. I did notice a few tiny cracks though, do you think these could be enough for water to get in?
pic_1.jpg
pic_2.jpg
I tried spraying water directly into the pipe with the garden hose, but that didn't reproduce the dripping sound.
According to the previous owner the roof is about 12 years old now. I'd assume that the gaskets/flashing were replaced at that time.
Spray water around the collar of the gasket (the lip where it connects with the stack). Have someone in the attic looking to see if there is any water dripping. If so, the solution is in my post earlier.
You can get retrofit boots that slide right over the old boot. Basically acts like an "umbrella" if the crack was along the boot/pipe penetration. If you can get on your roof it's an easy enough thing to try.
If there's any moisture in the drywall you could test with this moisture detector and maybe get a clue as to the source by moving it around. It will detect to about 1/2 inch deep.
Close metal objects will give a false positive though. https://www.canadiantire.ca/en/pdp/mast ... 4572p.html
Seeing how you vent / vent boot is, yes, it's not bad considering the age and I doubt that's the source of the leak...
No blockages in the vent pipe either (seems like you checked that too even if you didn't mention).
Only thing I can think of now considering you used a hose on that spot and only when it rains does it happen is: from another source outside (shingles?/flashing?) then drips to the area where you hear?
Or as others have said, moisture meter... It happening when it rains is the main "clue" working with.
