There is an almost sulpher type of odor coming from the shower stall but not really from the drain. I originally thought it was the tile/grout sealer but it isn't getting any better. The shower pan has been replaced and the walls, floor and ceiling are all natural stone tile. Please Help! Cliff

Was a silicone sealer used anywhere on this shower? That can leave a sulphur like smell. Try washing all of the stone and pan with 1:4 vinegar and water.

Thank you so much Tom. Will keep you posted.

Hey Don, who did the grouting 6 months ago? A pro would likely warranty his work.

One more question.. Could there be a possible chemical reaction between one of the cleaning products and the sealant/grout/natural stone?

Likely not but then we don't really know everything you have used. Some grout is more porous than others and yours sounds like maybe a poor installation. I would seal the drain with Saran wrap and duct tape then flood the pan with a mldewcide for several hours. Flush it with plenty of hot water and see how long it takes for the odor to return. If its mold it will be back after ssseveral weeks. If the smell is back in a day we are going to start thinking trap and vent issue.

Thank you for your idea. Night before last I filled the pan with Miracle brand disinfectant (which is a hospital grade mildewcide/deodorizer/fungalcide etc.for natural stone). The next morning no smell or throughout the day. Then that night (about 24 hours later) it was back as strong if not stronger than before. I only left it for about 30 minutes so we are going to strip the shower and then try deep cleaning again. I'll try a few hours this time. Also, we've had the plumber who installed all of the original plumbing to check all of the vents, drains etc. He gave a good look and found nothing. Any other thoughts?

Now if he was a good plumber he'd offer some insights here. What does he think this smells like, he would recognize sewer gas.

We originally thought it was a valve or faulty p trap. The plumber was able to trace the smell to the floors (it clings to all of the walls) and he did say that it did not smell like sewer gas. His description was that it smelled like sweaty laundry. The plumber said that the smell was strong but unlike anything he'd ever smelled on the job before. This was what led us back to checking out the tile/grout. The plumber was thorough and spent a couple of hours chasing the smell. The only reason we are still considering a plumbing issue is that our front loader washer is right before this shower on the sewer line. It appears to be hooked up corectly and there is no bubbling in the shower p trap when the washer drains but we've had countless problems with our laundry smelling foul from this washer. It seems more likely to be a tile/grout issue but we're open to any leads at this point.

Lets talk about that washer for a minute. Can you describe how the flexible washer drain hose is connected to your house drain.