We have a sewer smell in our master shower (upstairs). I'm embarrassed to say it's been going on for quite a while. It began with a very strong odor and shortly after a less pungent, but consistent, sewer smell. The odor seems to be strongest right after the shower is used.
What we have done:

1. Husband snaked drain himself. A little hair, but pretty much clean.

2. After a phone call to a veteran area plumber I poured vinegar and baking soda then boiling water down the drain. The smell may have gotten milder, but it was still noticeable.

3. Plumbers assistant came to investigate. He agreed that it was bacteria in the drain and advised bleach. I poured bleach/boiling water down drain. Smell still there.

4. New plumber visited stinky shower. He seemed thorough. He went as far as cutting a hole in the garage drywall below the shower to check the pipe configuration?
Climbed the roof and sprayed the hose down the showers vent pipe determining, I think, it wasn't blocked and used a plunger on the shower drain. He thinks it may be bacteria we are smelling.
Smell is still there.

5. Husband pours more vinegar, bleach and then boiling water down drain. Scrubbed as much drain as he could reach. Smell still there.

Other possibly important info:
After reading posts on this website I see that is important to note the master toilet makes a bubble when flushed. (Maybe separate problem- the toilet made a big bubble and was needing the handle to be held down to completely flush. Husband just replaced the junk? On the inside of the tank, the toilet still makes a bubble, however, smaller when flushed. The handle doesn't need to be held down anymore, but now it's doing a double flush.)

On advice from another post I had my daughter flush the toilet while I peered down the drain. There was no bubbling when the toilet was flushed but the water in the trap did move around. The smell did seem to get stronger as the toilet flushed. I also noticed water dripping/flowing down the side into the trap.

So what's next?

Heather

You have a clog below the toilet. Snake the toilet. If it still bubbles, snake the drain from any clean out you have. Once the toilet flushes without bubbles, go back to the bleach and boiling water. This time, let the bleach set over night, and boil in the morning.

I really don't know plumbing so sorry if this is a dumb question: Do I snake it right through the toilet or do I go through the vent on the roof? Is my husband's snake OK or should we call someone with a "professional snake."

Thanks for your help.

Heather

The easiest and cheapest thing is to run your husbands snake right through the toilet. It may do the job. You can also rent large electrically driven snakes like a professional uses. Go to the plumbing section of Lowe's or somewhere and look at toilets and the closet bend they set on. Notice the two 90's very soon after the toilet. You can also pull the toilet off and snake from the closet bend. When I want to nib around and not be bothered or buy anything, I always go to Lowe's. If I think I will need help, I go to Ace Hardware.

Professional snake? I once caught somebody's typo, and they never did explain what a work snake does. OK, they clean toilets for a living.

You also could have a vent not functioning properly, usually from a break or a blockage and then the gasses build up in the line and when you flush it will bubble or bloop and not flush well, and you will get an immiediate bad smell. Sometimes hard to determine if you have just utilized the toilet. But getting the vent clear and unobstructed will remedy this problem and you toilet will flush better.

I have run across ceramic tile showers that have lots of stinky water that holds in the bottom of the pan. You can not see it because it is under the tile and concrete base. Look into how tile showers are built and you will see that most of them will hold about 1/4 to 1/2 inch of water in the bottom of the pan.