septic smell in house. lots of questions.
Posted by Mike D on December 26, 19100 at 16:30:23:
This summer I moved into 4 year old house built w/ septic tank.

Septic tank smell arrived in the autumn.
No septic smell outside.

Autumn. Hmm. Must be when the themostatic attic fan stops kicking in.

I go to the attic. The smell is worst there. Found a vent pipe coming into the attic.

Called county inspections. They said the builder must have forgot to put on the studor vent.
I installed the studor vent. Tested it first. I'm sure I did it right.

Smell went away for a day. No smell in attic.

But smell came back.

It's not as bad in the attic, but I can still smell it up there a little -- about as bad as rest of house.

Could find no other open vent pipes in attic.

2 4" vent pipes go thru roof, so don't need studor vents.

Lots of studor vents thru rest of house. Under sinks everywhere.

Had septic tank pumped. Problem went away for a few days.

Fed bacteria to septic tanks. Problem not affected.

Had plumber come and look for problem. He couldn't find anything.

Have sniffed a lot of drains. Cannot find the source of the smell.


1) Any thing such as a smoke bomb I could flush down a toilet, to see what vents and whether I have any leaks in my vent pipes?

2) Any other way to find leaks?

3) Should I be able to find a vent pipe near the septic tank? Does methane etc. produced by septic tank go out thru roof, or is there a separate vent pipe for septic tanks that keep the tank from pushing bubbles through your toilet traps, etc.

4) Suggestions?

5) Any recommendations for a plumber here in North Atlanta that is an expert in these kinds of problems?

(I've paid a plumber and a septic tank person. Never really wanted to be an expert myself...)

Thanks for all advice.

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