I have a two story house built in 1914. It has a bathroom on each floor right above the other using a shared stack pipe / vent (our only vent pipe). In the basement we have a bell floor drain that I keep vegetable oil in.
Periodically when the second floor toilet is flushed, we get a sewer smell both in the downstairs bathroom and in the basement.
A few years ago, we found that a section of our stack pipe was cracked and had our plumber replace it.
Are there any cleaners would anyone recommend for putting down the drains? Down the main stack? Maintenance that I could do that would help eliminate the problem?
I’m thinking our lone vent is a big problem. Would the installation of an AAV help?
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Replies
Odds are you've got another crack. Though it might be worthwhile to try replacing the wax rings under the toilets.
If one of the wax rings was the problem wouldn't it also be leaking? We rarely experience the smell on the second floor (exception is when the HVAC unit is running).
Nope. You can have a gas leak without a (serious) water leak.
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Is the first floor sink or tub rarely used? Maybe the trap water level has evaporated to the point where a bit of vacuum caused by the flush breaks the seals. Run the water for a while in the first floor fixtures and add some more water and oil to the basement drain and try flushing again.
The first floor bathroom is used all the time. The second floor sink and toilet are used daily. The second floor clawfoot tub is rarely used.
I think you'll have to take the upstairs bath off the original vent stack and run a separate one. That's code, anyway.
>>I think you'll have to take the upstairs bath off the original vent stack and run a separate one. That's code, anyway.
That depends on vent stack size and fixture count.
1. Toilet cannot be the the upper fixture on a wet vent.
2. No toilets on waste stack.
I think the OP needs to at a minimum run a new drain from the 2nd floor toilet and tie it in to the basement after the floor drain fixture to prevent siphoning out his traps every time he flushes. And the toilet would work better if the new stack is vented or tied in to the main one in the attic.
The house was built in 1914. Plumbing may or may not have been done then, but newer code does not require a re-plumb of all old houses. I had the same configuration as the OP in my Victorian with two toilets on the wet vent and it all worked just dandy with no sewer odors. I also vote for checking out cracked pipe and/or snaking the vent, considering that's already been a problem.
It's worth a shot. OP, let us know how it works out!
For what it is worth is there any pvc tub or shower drains ?
These tend to develop a sewer gas smell if not cleaned regularly.
(fungus seems to attach to pvc but not copper or brass.)
If pvc try bleach and rinse.
Is there a washing machine anywhere on this stack potentially causing problems with sudsing?
Jeff