Sewer Vent

We just purchased out home with a septic tank. The septic was tested as part of our inspection and it passed. Once we moved in we started to notice a sewer odor in the basement only after we used the shower. Could this be a problem with the vent on the roof?

tonlyn

It might not be sewer gases at all. It could be a failed or poorly built shower pan. If the shower hadn't been used, it might have had a chance to dry out. Once you used it, the water could have rehydrated the mold, etc. Many showers are built without what is called a preslope. If not done that way, water tends to pool under the tile since it all can't drain. Eventually, if not used, it will dry out, but it could take a long time. Now, if it is not a tiled shower, that's not likely a possiblity. My unprofessional opinion.

odor

If you have any drains in the basement, they may need to have water poured into them to reseal their traps.

Deb

This is most likely not a vent problem.
As already mentioned, make sure that it actually is sewer gas. I go out on a fair amount of calls for sewer gas that aren't.
I would check all traps for water. Make sure that you check them all. Water can evaporate from p-traps if the drain is used infrequently, as hj mentioned. Partially clogged drains can siphon out p-traps.
Deb
The Pipewench

Sewer Vent Reply

Thank you all for answering! I should have mentioned in my question that the our only bathroom (with a bathtub shower) is on the first floor of our ranch home. We've made sure that all of the basement drains had water in them when we moved in. Our basement floor sits well below our septic tank. Would our basement drains still be tied into the rest of our plumbing and still be causing the odor?

Thanks again to all!

Tonlyn