Testing for an internal vent stack leak

[rmp]

Hi,

I am wondering if anyone here might be able to answer a quick question about determining whether or not there's an internal leak in a plumbing vent stack.
We live in a four-storey, multi-unit building and have been trying for months to find the source of a leak that caused water damage to several units. A roofing company told us the issue might be an internal leak in the plumbing vent stack. So we eventually found a "rooter" company who said they could test for an internal leak by sticking a hose inside the vent stack and running water down it. But when the guy got here, he said he wasn't able to get up on our roof, so he instead stood on a balcony and sort of sprayed water over the vent stack area instead. I have the feeling that what he did was likely not as effective as what he originally said he was going to do, but don't want to accuse him of doing the wrong thing, either. Are you able to tell me if this type of test needs to be done by sticking a hose right in the vent stack?

 

[Twowaxhack]

You’re obviously going to get a lot more water down the pipe by inserting the hose into the pipe.

I think I’d put a hose into the stack if I was going that direction with looking for a leak.

Of course it would be good to spray the area with water also.

 

[rmp]

You’re obviously going to get a lot more water down the pipe by inserting the hose into the pipe.

I think I’d put a hose into the stack if I was going that direction with looking for a leak.

Of course it would be good to spray the area with water also.

Thank you! That is what I figured. I thought, 'well, if he could have done it just as effectively by spraying it from below, why would he have suggested going up on the roof?' Makes sense.

 

[johnjh2o]

Do a smoke test.