Water Bubbling Up in Sink When Toilet is Flushed
LESLIE: Mary in Iowa, welcome to The Money Pit. What can we do for you today?
MARY: Hi, we have a toilet that when we flush it it gurgles up in the sink and this odd – well, bad smell comes out.
TOM: (chuckling) OK.
MARY: And I don’t know what to do about it.
TOM: Well, it’s a venting problem. The problem is that you don’t have enough air getting into the waste pipe. You see, as you flush the toilet you’re going to have, you know, a couple of gallons of water go down the waste pipe very quickly. That water has to be replaced; that volume has to be replaced by air. And so if your toilet is not vented properly, there’s no way for the air to get back in there, it tries to draw the air from the room by sort of gurgling and that’s the bubbles and the gurgling and the sort of the sucking sound that you hear.
LESLIE: It’s gulping for breath.
TOM: Yeah, that’s right. It’s starving for air. And so this is a problem that can be solved by a plumber through the installation of an additional vent. If it’s possible to get the vent up through the roof and out that’s fine but there are other ways to install vents to the inside of the house that have sort of ball valves on them so they let air in but they don’t let smell out. But this is a simple venting issue and that’s going to solve it.
MARY: So would it be just venting that toilet or just venting the sink or both or …?
TOM: It actually could be somewhere in the plumbing line because they’re all connected. As you’ve noticed, you hear this bubbling in different places. It could be vented in one of a number of places but it is a venting issue and that’s what has to be done.
Mary, thanks so much for calling us at 888-MONEY-PIT.