Water leaking from vent pipe

die_of_ennui

I think I have a vent pipe issue. When I fill the kitchen sink with water, then let it drain, after a few seconds water comes pouring out in the basement near the vent pipe. Not sure if this matters, but if even if the sink is filled with clean water, it smells awful when it leaks out. It does not leak when I just run the tap though.

House was built in the 50s, I think the pipes are PVC (black, "Type 1 Grade 2 DWV Pipe" printed on them in yellow")

This happened the first time yesterday, although we do not often fill the sink with water, just use the dishwasher instead. I don't think this happens when the dishwasher runs, but I'm scared to let it run a full cycle.

We've had some weather changes lately, from 10C to -20C within the last week (cold and snowy now) I'm wondering if this could be the issue?

There's a clean out valve in the basement at the bottom of the pipe, but I'd prefer to only have to open it as a last resort as it's been half drywalled over by the last owners.

I'm thinking about grabbing the ladder and checking out the roof, but I'm not sure what to look for, or if there's a better option.

I don't really know much about plumbing, just trying to learn as I go along.

Alan

Your terminoligy seems a little off, otherwise i'm confused....

Your kitchen is upstairs from the basement? Normally the vent is above the kitchen sink, or at least the way we plumb houses out in oregon.

If your pipes are leaking when you run water out of the kitchen sink then it should be a drain and not a vent. The only thing i can suggest is to run water continually and see if you can figure out where it's coming from visually.

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Journeyman Plumber

AllanJ

There's a crack or a hole somewhere in the path of the water going down the sink drain.

When you pull the stopper and the sinkful of water goes down, the gallons per minute out is much more compared with just running the faucet into an empty sink, so water is more likely to leak from a hole along the way that it might otherwise miss.

I don't think checking the roof will do any good.

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The average homeowner who lost his house in the Oklahoma tornadoes should move for good and not rebuild. Too much complexity watchdogging the contractor. Too much a chance to be defrauded.

plumberinlaw

here is what I see around where I live. Houses built in the 50's use cast iron for drains if it is plastic from the basement to the kitchen it has probably been replaced. where you describe your underfloor line is a common place for cast iron to rot out. There is no valve in a cleanout it is just a cleanout with a cap. the way to determine if the line has failed is to send a camera down the line