Possible plumbing issue in new home. (moved from NC forum) (floor, drains)

[cityloop]

I have been in my new home for less than a year now. I have a first floor guest bedroom with a full bath. There is currently a foul smell coming from the drain pipe in the shower from this guest bedroom bath (This smells like sewage). Since we moved in, this shower has only been used once by a guest (a few months ago). Does any one in this forum have an idea of why we are getting that bad smell coming from the drain pipe?

[wanderintonc]

Unused drains make that stink. It's sewer gas. You should run the faucet (therefore using the drain) every week or so to keep the gas out. It's not a plumbing problem, but a normal thing.

[MikeJaquish]

Originally Posted by wanderintonc

Unused drains make that stink. It's sewer gas. You should run the faucet (therefore using the drain) every week or so to keep the gas out. It's not a plumbing problem, but a normal thing.

Right.
There is a trap in the floor under the drain.
The trap should have water in it, to prevent the sewer gas from coming into the house.

As the trap water evaporates over a period of months, it may get low enought that sewer gas may enter the house.
Running a little water in there regularly will keep the trap water level high enough to keep this from happening.

[cityloop]

Thanks for your postings on this. It is these knowledgeable tips from people like you that make City data so special!

[harry chickpea]

If you don't want to have to run water in the drain every week, pour in an ounce or so of cooking oil to prevent evaporation. However... if the smell returns quickly, you may have a birds nest or some other clog in the stack pipe that normalizes the air pressure in the sewer line, and prevents a toilet flush or other useage from sucking the water out of the traps.