Few household problems are as off-putting as when your toilet smells like sewage. Beyond the unpleasant odor, it’s often a sign of underlying plumbing issues that could worsen. If ignored, even small faults can lead to big headaches and large repair bills. In this guide, we’ll uncover the most common causes of toilet odors, share practical step-by-step solutions you can try yourself, and explain when it’s best to call a plumber. By the end, you’ll know exactly how to eliminate the smell and keep your bathroom fresh!
Common Causes of Toilet Bowl Odor
Knowing why your toilet bowl stinks lets you target solutions effectively, saving you both time and repair bills later. Here are some common causes for your troubleshooting.
1. Poor Ventilation
Poor bathroom ventilation can cause odors to linger and persist. If the vent is blocked by debris, like leaves, bird nests, or ice, sewer gases can become trapped and forced back into your home, causing a strong odor. The situation becomes worse if there are inadequate exhaust fans or no windows.
2. Clogged Drains
A partial blockage can be the source of odors. Even if the toilet appears to flush normally, accumulated trash, toilet paper, or other debris can trap odors and cause them to persist.
3. Lack of Deep Cleaning
Urine spilled on floors, walls, and the toilet bowl base can be absorbed by porous materials, causing strong, lingering odors. Furthermore, the high moisture of the toilet rim can encourage mold growth, resulting in a musty or sour odor. The toilet smells like sewage when these areas lack deep cleaning.
4. Damaged Wax Ring
The wax ring provides an airtight seal between the toilet base and the drainpipe. When it is damaged or deteriorates over time, sewer gases and small amounts of water or waste can leak out of the toilet bowl. This causes your toilet to smell like sewage. A wobbling or rocking toilet is a common sign of a damaged wax ring.
5. Cracked or Leaking Toilet
Microscopic cracks in the toilet porcelain can cause slow leaks, lowering the water level in the bowl and allowing sewer gases to seep out. Similarly, any leaks in the plumbing can release sewer gases into the surrounding environment.
6. Dry P-trap
A P-trap is a U-shaped pipe located under the toilet. It contains a small amount of water that acts as a seal. This prevents sewer gases from traveling through the pipe and into the bathroom. If the toilet is not used regularly, the water in the P-trap can evaporate, allowing sewer gases to escape and produce an unpleasant toilet odor. A sulfurous smell is a typical sign of a dry P-trap.
How to Get Rid of the Toilet Sewer Odor?
Once you’ve identified why your toilet smells like sewage, the real win is tackling the problem at its source. Here are actionable DIY solutions to get rid of the situation.
Method 1. Deep Cleaning
First, wipe down all surfaces, including the base, the floor around the toilet, and the area behind the toilet. Don’t overlook the rim, where bacteria and mold easily harbor. Sometimes, it is the water that makes the strange odor. If possible, empty the tank for a thorough clean.
The toilet design plays a vital role in reducing your cleaning tasks. For instance, it is easier to clean the base with the back-to-wall toilets. Furthermore, a concealed tank and plumbing means less exposed toilet surface and significantly fewer gaps between the wall and toilet seat. This helps reduce the moisture and bacteria that can cause toilet odors.
Method 2. Clear the Clog
Use a plunger or toilet unplug (coil) to clear any clogs. As long as the clog isn’t persistent or recurring, this method will take effect quickly.
Method 3. Troubleshoot Plumbing Issues
If cleaning doesn’t resolve the problem, something may be wrong with the plumbing. For toilets that haven’t been used for a long time, refill the P-trap by flushing them a few times. This will create a new seal to prevent sewer gases from entering.
Method 4. Check the Wax Ring
If you notice the toilet shakes when flushing or leaks from the base, the wax ring seal may be damaged. You will need to disassemble the toilet and replace the wax ring.
Method 5. Install an Exhaust Fan
Proper ventilation is crucial for eliminating bathroom odors. If your bathroom doesn’t have a window or exhaust fan, consider installing one. An exhaust fan will vent moisture and odors outside, preventing them from accumulating.
Method 6. Clear the Vent Duct
A clogged vent creates a vacuum, drawing air (and sewer gases) out of the toilet. If convenient, you can inspect the vent ducts on the roof to see if they’re clogged with debris like leaves or bird nests. However, for more complex ductwork, such as in apartments, it’s best to hire a professional.
When It’s Time to Call a Plumber?
If you’ve tried the above steps and the toilet odor persists, it’s time to call plumbers. They have the tools and expertise to diagnose and help out. Here are the situations where it’s best to get a professional involved.
- Persistent sewer odor: If a toilet keeps smelling like sewage despite a deep cleaning, something may be wrong with the vent pipe or main sewer line.
- Hidden water leaks: Hidden leaks behind walls or under floors can cause expensive structural damage over time. A plumber can use specialized cameras to inspect your drainpipes for cracks or leaks.
- Slow drains in multiple fixtures: A single clogged sink is manageable, but if tubs, sinks, and showers all drain slowly together, the problem is likely in the main line and should be inspected by a plumber.
- Sudden drops of water pressure: Consistent low pressure may indicate a supply line problem or mineral buildup that needs specialized tools.
- Gurgling sounds from drains: Often signals trapped air from a clog or venting problem. A plumber should check it before it worsens.
Conclusion
If your toilet smells like sewage, don’t ignore it. Odors often signal underlying problems. Begin with simple fixes, such as sealing leaks, cleaning drains, or replacing worn parts. If the smell lingers after your best efforts, it’s time to bring in a professional. You might also consider a back-to-wall toilet. While it won’t eliminate sewer gases on its own, its design can minimize odor buildup and help keep your bathroom fresher and more comfortable.
FAQs
Is the sewer smell from the toilet toxic?
Sewer gas from the toilet contains toxic substances, like hydrogen sulfide and ammonia. It can be extremely harmful, even fatal, in high concentrations or confined spaces.
Will bleach get rid of the sewer smell?
Bleach helps get rid of the sewer smell, but temporarily. If the smell is due to a larger plumbing issue, like a dry P-trap, a broken wax ring, or a blocked vent pipe, it will likely return.
Are sewer gases harmful to my health?
Yes, sewer gases can be harmful. Low-level exposure can cause headaches, nausea, and eye irritation. At high concentrations, especially in poorly ventilated areas, sewer gas can lead to unconsciousness or even death.
