A gurgling toilet is more than an unpleasant sound—it’s a warning sign of underlying plumbing issues. Understanding the causes and solutions for a gurgling toilet can help you address the issue quickly and maintain a healthy plumbing system. Read our guide to learn more about the reasons behind toilet gurgling, how to diagnose the problem, and various methods to fix it.
What Causes a Toilet to Gurgle?
A gurgling toilet is typically caused by negative air pressure in the drain pipes. This happens when there’s a blockage in the plumbing system, often in the vent stack. As plumbing and heating expert Richard Trethewey explains, “Most people think that those small pipes that stick out of a roof are there to exhaust sewage smells, and that’s true. But they also equalize the air pressure in the drain pipes so waste water can flow freely.”
When these vent pipes become blocked, it creates a vacuum effect in the plumbing system. As water drains from other fixtures, it can pull air through the toilet, causing the gurgling sound.
Common causes of vent blockages include:
- Ice or snow accumulation
- Debris such as leaves or twigs
- Animal nests or carcasses
- Excessive toilet paper use
Common Symptoms of a Gurgling Toilet
Besides the characteristic gurgling sound, other symptoms may indicate a problem with your toilet’s venting system. Quick action can help you prevent more severe plumbing problems. Here’s what to look out for:
- Water level fluctuations in the bowl
- Slow draining in other fixtures
- Foul odors emanating from drains
- Bubbles in the toilet bowl when other fixtures are in use
Diagnosing the Gurgling Problem
Before attempting repairs, diagnose the cause of your problem. This involves checking for clogs in the toilet itself and inspecting the vent stack for possible blockages.
Checking for Clogs
Start by examining the toilet for any visible obstructions. Here’s a simple process to follow:
- Flush the toilet and observe the water flow.
- If the water drains slowly or incompletely, there may be a clog in the toilet trap or drain line.
- Use a plunger to attempt to clear any minor blockages.
- If plunging doesn’t resolve the issue, the problem may lie further down the drain line or in the vent system.
Inspecting the Vent Stack
If you’ve ruled out a simple clog, the next step is to inspect the vent stack. “The giant finger blocking your roof vent could be ice or snow or debris or even an animal carcass,” Trethewey notes. Identifying the type of blockage will help determine the best course of action for clearing it. This may require accessing your roof, so exercise caution or consider hiring a professional if you’re uncomfortable with heights.
- Locate the vent pipe on your roof. It’s typically a 3- or 4-inch pipe extending from the roof.
- Check for visible obstructions at the vent opening, such as leaves, twigs, or animal nests.
- If possible, shine a flashlight down the vent to look for any blockages further down.
- In colder climates, check for ice buildup, which can completely block the vent.
DIY Solutions for a Gurgling Toilet
Once you’ve diagnosed the problem, there are several DIY solutions you can try to fix your toilet.
Plunging Techniques
Plunging is often the first line of defense against toilet clogs and can sometimes resolve gurgling issues. Follow these steps:
- Ensure there’s enough water in the bowl to cover the plunger head.
- Place the plunger over the toilet drain to create a seal.
- Push down firmly and pull up quickly, repeating the motion several times.
- Flush the toilet to see if the gurgling has stopped.
If plunging doesn’t solve the problem, the issue may be further down the drain line or in the vent system.
Using a Plumbing Snake
For more stubborn clogs, a plumbing snake (also called an auger) can be effective. Here’s how to use one:
- Insert the end of the snake into the toilet bowl.
- Slowly feed the snake into the drain, turning the handle clockwise.
- When you feel resistance, continue turning the snake to break through the clog.
- Slowly retract the snake, which may bring up the source of the blockage.
- Flush the toilet to check if the gurgling has stopped.
Professional Remedies for Persistent Gurgling
When DIY solutions fail, it’s time to consider professional remedies. Plumbers have specialized tools and expertise to address complex plumbing issues, particularly those involving vent stacks or deep clogs in the drain system. Here are some of the methods they may try.
Hydro Jetting
Hydro jetting is a powerful method professionals use to clear stubborn clogs and buildup in pipes. This process involves the following steps:
- Inserting a high-pressure hose into the plumbing system
- Using water pressure up to 4000 PSI to blast away debris and buildup
- Thoroughly cleaning the entire pipe, not just breaking through a single clog
Camera Inspection
For difficult-to-diagnose issues, plumbers may use camera inspection technology. Camera inspections can reveal issues such as tree root intrusions, pipe collapses, or misaligned joints that may be causing the gurgling problem. A plumber will do the following:
- Insert a small, waterproof camera attached to a flexible rod into the plumbing system
- View real-time footage of the pipe’s interior on a monitor
- Identify the exact location and nature of any blockages or damage
Gurgling Toilets and Septic Systems
For homes with septic systems, a gurgling toilet can indicate septic tank issues. Septic tanks play a vital role in waste management for homes not connected to municipal sewer systems. Here’s how they can affect toilet function:
- Full septic tanks can cause waste to back up into the home’s plumbing.
- Clogged or damaged septic tank baffles can lead to improper waste flow.
- Issues with the septic drain field can cause the entire system to malfunction.
Septic Tank Maintenance
Regular septic tank maintenance is essential to prevent plumbing issues. Have your septic tank inspected every three to five years and pump the tank as recommended by professionals. Additionally, avoid flushing nonbiodegradable items or harsh chemicals, and be mindful of water usage to prevent overloading the system.
Preventing Future Toilet Gurgling Issues
Regular maintenance is key to a healthy plumbing system. It’s often easier and cheaper than fixing a problem after it occurs or when it’s time to upgrade your toilet.
Schedule annual plumbing inspections to catch potential issues early. Clean vent stack openings regularly, especially after storms or high winds. If you live in a colder climate, insulate vent pipes to prevent ice buildup. Consider installing vent pipe extensions or covers to prevent debris and animal entry. “If animals are to blame, cover the end of the pipe with hardware cloth held in place with a hose clamp,” Tretheway says
Proper plumbing use can also help prevent potential issues. Avoid flushing nonbiodegradable items down toilets, and use toilet paper sparingly to prevent clogs. If there are drains in your home that you rarely use, run water periodically to maintain trap seals. Also, never pour grease or oil down drains, which can cause buildup over time.
When To Call a Plumber
You can resolve some toilet issues on your own, but there are situations where we recommend hiring professional help. Recognizing these signs can prevent minor problems from escalating into major plumbing disasters.
Call a plumber immediately if you notice any of the following:
- Multiple drains gurgling or backing up simultaneously
- Sewage odors coming from drains or yard
- Water backing up into tubs or showers when toilets are flushed
- Persistent gurgling despite DIY attempts to clear the problem
These symptoms may indicate more severe issues, like main sewer line blockages or damage to your home’s plumbing system. Ignoring a gurgling toilet can also be risky, potentially causing sewer gas to enter your home, an increased likelihood of sewage backups, potential damage to your home’s foundation or structure, and higher repair costs if the problem worsens over time.
