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Re: sewer venting problem

I think I solved the problem by installing a 2d "extend-a-ring" in order to bring it above the level of the new tile. After tiling the floor I used only one ring extension on the flange but when I re-examined the situation I could see that the single ring/collar was only just level with the new tile and not slightly above it as it should be.

Since I added the 2d collar I have not had a problem with the smell. I was surprised that even though it wasn't leaking water, I had sewer gas coming thru it as well as the tub drain when there was a South wind. It doesn't really make sense to me but that's what it was.

At least it was a simple fix.

Thanks to all that offered advice.


Re: sewer venting problem

Glad you found it... thanks for the update.:)

Re: sewer venting problem


Am not there to see things firsthand, so am wondering about this crawl-space of yours. I don't recall you saying whether this crawl-space is "open" or "closed" (walled off from the world at large).

Thought being that if the crawl is walled off, but its south wall is not really all that tight (poorly fitting entrance door or similar), then a south wind may pressurize the space. If your toilet wasn't actually sealed well to the flange, then some amount of septic gas would be leaking into and accumulating in the space at all times. The gas could then enter the living space thru any route/crack it could find at any time (around that heating duct was its easiest route maybe?)........but when the space was pressurized by a south wind, the gas would be forced thru more penetrations/cracks and hence the greatest odors at that time. Just a thought.

Reminds me of a situation I came across this last fall when I stopped into one of the local vet clinics to grab some amoxicillin for one of our cats. The girl behind the counter is a friend. She mentioned to me in passing that they had a terrible odor in the clinic basement recently. This is a walk-out style basement where they have the kennels and cages for any overnight boarders and such. So down I go to have a look/see. At first glances, I can't see any major and obvious problems, but the odor was truely overwhelming, so it's time for some more investigation. I eventually grabbed one of the floor drain grates/covers and flipped it off to see if there was water in the trap. Good grief! The clean-out drain plug had been removed. That she said because the drain wouldn't take water and they discovered that if they removed that "little pluggie thing", it would. So......there had been sewer gas entering there now for about two months. I simply jettted the drain with a common nozzle on a garden hose and it drained just dandy. (Some cat litter and such as all that was blocking the trap.) She didn't know what they'd done with the plug, so I grabbed one from my truck. Before leaving I thought it best to look at all five floor drains and discovered that they'd removed the plug from ALL the drains! Yikes. That required a trip to get more plugs and a few more simple drain jettings. Stopped in a couple days later and no more sewer odor. Imagine that.

sewer venting problem -clawfoot tub

I recently installed a clawfoot tub in my 1883 home and have noticed sewer gas. It is most certainly coming from the clawfoot tub overfill vent (inside the tube). I know this for certain because there are small black fly's that accompany this awful sewer gas and they come through the overflo vent.
I dissembled the drain and vent assembly and noticed that the internal stopper (that rises or lowers to allow the tub to hold water) is like a small soupcan within the plumbing outlet piping. This small 'soupcap' does not have a top or bottom portion...just the round side and is attached via a linkage to the vent assembly.
This works great for holding water inside the tub but does not prevent sewer gas from proceeding past it and coming into the bathroom via the bathtub overfill vent.
My question is this. Should I have installed a S trap below the drain and vent assembly T ?
Thank You,

A. Spruce
Re: sewer venting problem -clawfoot tub
romanmatt wrote:

My question is this. Should I have installed a S trap below the drain and vent assembly T ?

Uh, yup! ;)

All drains require a trap of some sort to prevent sewer gases from coming back out. Whether you see them or not, they're there. BTW, the stopper in the tub overflow is for stopping water from escaping the tub only, not preventing gas or anything else from coming back out. As a matter of fact, if it were a solid piece, then the overflow would not function because any water that entered couldn't get past the solid stopper, hence the through flow design.

Hope the info helps. :)

Re: sewer venting problem

To Goldhiller:

That exaplantion makes perfect sense. The crawl space is sealed off, outside of one VERY small entry hole on the N side, so your pressurization theory seems to explain the problem. The smell really did seem to come from several places when the South wind blew. Granted, we've not had much S wind recently here in KS but we have had some and I've not had even a hint of a scent since adding the extra ring -nor when then furnace is on.

It's simple physics, I guess.

Re: sewer venting problem

so my first post was right after all. looookie there :D

Re: sewer venting problem

In the words of Hulk Hogan..."You are so right, brother"

Thanks, Havanagranite.

Re: sewer venting problem

obviously from my name that isn't my specialty. but I have been down that road before. when a bath room was retiled and they thought it was coming out of the tub and sink, but I knew who did the tile work and of course it takes all of what maybe a total of 5 minutes to take out the toilet and check the wax ring and upon looking at it you could see that it never made contact with the toilet. so no seal was ever made. kind of one of those no one light a match things:)

Re: sewer venting problem

I have had a similar problem with my one downstairs bath/toilet, and one upstairs. No problem in my master bath/toilet thought. But the sewer odor really comes out when the toilets are flushed. I did replace my toilet downstairs about a year ago...after reading this, I am thinking my wax ring didn't seal well. But would that also cause the upstairs toilet smell as well?
I thought my vent as possibly plugged on the roof....so I ran a hose down to clean it out. I actually have two vents coming from roof. I am thinking two of the toilets are on one, and one of toilets on another.
So would a bad wax seal on my downstairs possibly cause both of my toilets to have a smell, one upstairs as well??
Thanks for reply.


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