Sewer smell in bathroom but can't find the source
The smell is usually sewer gas escaping from hidden plumbing defects like cracked or separated vent pipes, missing drain caps, or poorly installed toilet wax rings. Because these leaks happen behind drywall or inside enclosed tub panels, they are difficult to spot even with a snake camera. People often endure the stench for years before finally tearing open the walls to locate the exact break.
What people tried
Every workaround mentioned in the threads below. We haven’t tested any of them — and nobody here is claiming they worked.
Found another way around this?
Share your steps and trade-offs so fellow engineers don't have to reinvent the wheel. No account required.
Sewer smell in bathroom but can't find the source
- 1running water occasionally to keep the P-trap from drying outDid this help you?
- 2inspecting enclosed cavities with a snake cameraDid this help you?
- 3temporarily stuffing insulation into the panel to test for airflowDid this help you?
- 4using a removable magnetic cover instead of a solid sealed panel to avoid permanently trapping moistureDid this help you?
- 5Calling the original builder's warranty contractors repeatedly to no avail.Did this help you?
- 6Replacing the toilet entirely in hopes it fixes the issue.Did this help you?
- 7Installing external ventilation pipes without identifying the actual leak.Did this help you?
- 8Enduring the smell for years.Did this help you?
In their words
Unedited, grouped by where they were said, most upvoted first within each place, each linked to the thread it came from.
“I've been dealing with a horrible sewer smell in my en-suite bathroom for almost two years, and despite everything that's been tried, nothing seems to fix it.”source ↗
“We had a sewer smell in our bathroom for two years. We had to remove drywall to discover the vent stack was separated and broken in half.”source ↗
“This happened to me after some plumbers cleared roots from drainage line. They left the cap off and I didn't know any better.”source ↗
“I had something similar, and it was making me lose my mind. It turned out being a poorly installed wax ring, which allowed water under the floor.”source ↗
“I caught stink waves eventually and turned out to be an old cast iron vent terminated in the wall.”source ↗
“Every year when the weather gets colder, a musty smell comes from the grated access panel to our jetted tub.”source ↗
“I’m at my wit’s end with this smell and would appreciate any advice!”source ↗
“had a similar issue with my tub and it was dead simple once I figured it out, the vent pipe connecting to the drain had a tiny crack letting sewer gas seep through”source ↗
“It’s so hard to look around in there even with the snake camera lol.”source ↗
Where this came up
People with this problem also raised
- 10How do I find the source of a mysterious bathroom leak?
- 2Strong gas smell in room after new pipe installation
- 5Dishwasher has a funky smell but looks visually clean
- 3Why does my water heater closet smell bad?
- 2Where is the black debris clogging my shower head coming from?
- 6How to get rid of a lingering musty smell after water damage