Hi,
We've been having problems with a horrible odor coming from our master shower/tub drains. What we have tried:
- Running water in the tub to fill the p-trap
- Draino
- Bleach/hot water
- Plumber snaked the shower drain (seemed to improve for a few months then the odor came back - got much worse after I cleaned the shower with CLR)

Any other suggestions? Please help!

Thanks,

Laura

What type of odor do you smell? Is it sewage or a musty rotten smell?

I don't know the difference between a sewage smell and a musty rotten smell, but I'll guess sewage just because it seems grosser and since we did have the drain snaked a few months ago.

Thanks,

Laura

I don't know how to explain this without coming off as a jerk but a sewage smell is poop gas, just smells like poop. A musty odor would be like a wet tennis shoe afer 3 days in the rain. What exactlt did the plumber do and what did he say he found to be the problem? Where did he insert his sanke? Try pouring two cups of cooking oil into the drain and let it sit for a few days, does the smell stop completely?

LOL! No, you're not coming off as a jerk at all! I understand that it's nearly impossible to give suggestions with almost no information to go on.

I personally don't think it smells like poop. It smells more like the tennis shoe you described to me.

The plumber told me it was all the hair and gunk in the drain. He snaked it from the shower. The tub gets no use. He did suggest we run water in the tub now and then to fill the p-trap though. I tried this yesterday and it didn't seem to help.

I have never tried pouring oil down the shower drain. What is the purpose for this? Once I pour the oil down the drain, should I not use the shower for a few days?

Could it really get that clogged again just after a few month? We moved into the house 6 years ago and had no problems until a year ago. No problems in any of the other drains in the house although the smell by also be coming from the sink drains in the same bathroom as the shower and tub that the problem is coming from.

Thanks a ton for trying to help! I really appreciate it.

Laura

OK try this old concoction down the drain. Mix 1/2 cup of table salt with 1/2 cup of baking soda and then dump in the drain followed by a cup of vinegar. Watch the bubbles foam up and go to bed. Next day dump 2 buckets or really hot water down the drain, smelling better yet?

Sure, what the heck? What do you think is causing it? -Laura

This may be helpful,
Odors coming from drains are a common problem in many homes. Some people only have the problem when they run water in a sink or a bathtub. The source of the odor in almost all of these instances is a buildup of biofilm on the sides of the pipes that connect the sink or fixture to the actual P-shaped trap under the fixture. This vertical tailpiece pipe can accumulate a seething bacteria-filled organic layer of slime over time. When water rushes past the slime, it can dislodge some of the molecules into the air and they waft up out of the sink and into your nose.



Biofilm on the drainpipe leaving a shower or any fixture can be a source of odors. Look at the horrible black goo inside the drain! To eliminate biofilm as the source of the odor, take the chrome or brass strainer cover off the shower drain so you can see into the drain pipe. Use soap and water and a larger-diameter bottle brush to thoroughly clean the underside of the strainer, the bowl-shaped drain assembly under the strainer as well as the sides of the vertical drain pipe that extends downward into the p-trap. Rinse thoroughly with clean water until the entire drain is perfectly clean. If the odor still persists, it is time to move on.

Check for mold in the shower and areas near the shower. Active mold growth produces odor. That musty odor you smell when around mold is actually a puff of gas that ejects the mold spore from the mold organism. Imagine if hundreds, thousands or tens of thousands of small mold spores are being ejected each day in your shower. This could easily produce enough gas for you to smell. Remember, this mold could be behind the shower tile or walls and hard to discover. A recent leak that is still invisible could be the source of water that is fueling the mold growth.

A dead animal that somehow found its way into the wall space next to the shower or under the shower assembly could be the source of the odor. This is a remote possibility and the stench of a decaying animal is very distinctive and quite unlike the odor produced by sewer gas or biofilm from a drain assembly.


If this shower shares a common wall with a closet or some other wall surface that can be sacrificed, it is time to cut into the wall(s) to see behind and under the acrylic shower assembly. The first holes can be down low towards the floor so that you can see under the shower pan. Purchase an inexpensive makeup compact mirror and attach it to a stick so you can see around any corners or obstructions under the shower pan. Use a flashlight with the mirror to look up the wall cavities as much as possible to see signs of mold growth.

Odors from drains are voices telling you something is wrong. Think of them as low-powered smoke detectors. This is especially true if the source of the odor is some form of mold. It is not uncommon for a water leak to remain invisible for weeks or months and cause mold to bloom in a hidden location.

Add to this the power of the average human's sense of smell. You would be shocked at how few odor molecules it takes to trigger a response. Natural gas is a great example of this. In its pure state, natural gas is odorless. Gas companies add mercaptan chemicals to the gas so we can smell it if there is a dangerous gas leak. Believe it or not, you can easily smell mercaptans at a concentration level of one-half one part mercaptan to 1,000,000 parts of air!
Good luck, Tom

I'll add something. Fixtures with no use cause the traps to dry out over time which allows sewer gas to enter the home. Ballenger's cooking oil won't evaporate like water will. It will also have a harder time being sucked out, if there are other plumbing issues.

There is a trap for every fixture. The toilet has an integral trap.

How old is the bathroom? How many fixtures in it? Is it a shower as well or only a tub?

The house is 16 years old. It has a tub and separate shower. It has 2 sinks nearby. The odors seem to be coming from all drains.

Short of tearing out the shower and starting over, I believe I have the solution to the foul rotten egg smell coming from a tile or other shower with shower pan liners. The smell is probably not coming from the drain but the space between the floor of the shower and the shower pan liner. The design of the shower drain has openings that are intended to direct water that seeps through the grout or other cracks of the shower into the shower pan liner down the drain. If the mold or bacteria is in this area, simply poring bleach into the drain to settle in the p-trap will not affect the mold or bacteria.

You need to take off the drain cover and plug up your drain about 4 inches below the opening or just past the openings that allow the water to drain from between the floor of the shower and the shower pan liner. Pour bleach into the plugged up drain until you have a good standing of bleach in the bottom of the shower. You may want to even fill it until the whole bottom of the shower is covered with bleach. This should force the bleach into the cavity between the floor of the shower and the shower pan liner. Let it set all day or until the next shower. I could not get a good seal down my drain so it would slowly drain. You may want to add boiling water before you unplug it and let it all drain out. Do make sure that whatever you put down the drain as a stop that you can get it out. I hope this works for you. I did for me. You may have to repeat on a regular (weekly) basis for a while.

Hi, I was going to sugest the vinegar and baking soda, and to scrub the black guck from the drain, I was also going to suggest (I've never tried this or heard of it, but you never know) spray some Frebreeze down the drain. At least your bathroom will smell nice for a while!
Grumpy Old Lady (not really)