Reasons Why Your Toilet Constantly Smells Bad (And What To Do About It)

While a toilet is a household staple in almost every home in the United States, the ongoing fight against its bad smells can be frustrating. It's common to take on these issues with solutions focusing on temporary fixes instead of addressing the core cause. You want to get to the root of the problem with pesky odors and consider the overlooked or unexpected reasons why they don't go away despite your best efforts. From hidden causes like biofilm buildup in the pipe walls to a broken-down wax seal, each potential cause contributes to the lingering odor.

Unlike a lot of advice that skims the surface of this problem, you want to figure out how these problems last and how to get rid of them. Understanding that some things you try might not work is critical as well. For example, misusing certain cleaning chemicals can make the smell worse, and not having good ventilation in your bathroom turns it into a space for mold to grow. You need actionable solutions to address these issues, and by focusing on them, you can permanently get rid of odors instead of just masking them.

The vent pipe works to regulate the air pressure inside your pipes and let the sewer gasses safely escape from the house. This vertical pipe runs from the drain system to the outside, usually through the roof. However, external debris can block it, including twigs, leaves, and bird nests, especially in areas with a lot of wildlife or foliage. When it gets blocked, it disrupts or stops the normal airflow through your plumbing system, stopping the gasses from escaping. Instead of getting vented outside, they get forced back into the pipes and the bathroom, leading to an odor. Also, disrupting the plumbing's venting system impacts how well your water drains, leading to gurgling noises from the toilet and drains.

Cleaning the blockage in the vent pipe will restore the venting process for the sewer gasses and get rid of the smell. The first thing to do is look at the vent opening, either on the ground or from the roof, and look for a visible blockage. If you see visible blockages, carefully remove them with your hand or a plumber's snake. You may need a professional for blockages that are further into the system. Plumbers have specialized tools and equipment, like high-pressure water jets and motorized augers, that clear obstructions without causing damage. A plumber can also inspect the vent pipe to ensure no hidden issues are causing a blockage, like structural damage.

Sewer line issues, especially leaks or cracks, are a considerable risk to your home's comfort and hygiene. These cracks or leaks allow sewer gasses to escape; they are health hazards and smell unpleasant. Sewer lines are supposed to be airtight except for the vent stacks that let gasses safely escape through the roof. However, when there are loose connections, breaks, or cracks, the gasses enter your home and can cause a lingering odor that smells like sewage or rotten eggs. Smelling these odors tells you that your sewer system's integrity is compromised, allowing methane and other harmful gasses in. To make it more challenging, these problems may not be visible as they could happen in the pipes leading away from the deep underground homes. Simple wear and tear is a significant cause, as are tree roots growing into the sewer system pipes.

Fixing any sewer line issues requires you to hire a professional due to the possible health risks and the complexity of the project. If you think the bad smell is due to faulty sewer lines, contact a qualified plumber specializing in sewer repair services. They have the knowledge and tools to do a thorough inspection using cameras and other equipment to find the exact location and cause of the problem. Once they pinpoint the problem, they'll recommend a fix, and this could be anything from repairing only the damaged portion to replacing the whole thing.

The wax seal is under your toilet and plays a massive role in keeping your bathroom odor-free and sanitary. It creates a gas and water-tight seal between the drainpipe and toilet base. Over time, this wax seal will break down due to regular wear and tear, toilet position shifts, or temperature fluctuations. It won't work correctly as it deteriorates, and sewer gas and water can leak into your bathroom. Water leaks damage the bathroom floor while causing rot, and sewer gas leaks allow odors and potentially harmful gasses into the bathroom. Wax seal issues are common problems with older bathrooms or ones that get a lot of use.

Fixing a worn wax seal is a project for which you'll need expertise. The solution is to replace the old wax seal with a new one, and you have to remove the toilet to get to the seal underneath the base. So, it's common to turn off the water supply, drain the toilet, unscrew it from the floor, and carefully lift it away. Once you remove the old seal, clean the area thoroughly before putting the new wax seal on. It has to have a tight fit to safeguard against water leaks or odor issues. Since this is such a labor-intensive process, many people hire plumbers because it lowers the risks of damaging anything or installing it incorrectly.

Clogged drains are a common plumbing problem with enormous consequences for the bathroom's odor and cleanliness, especially in the toilet or the pipes running from it. Clogs happen when waste material, foreign objects, toilet paper, or wet wipes stop or slow the sewage flow through the pipe system. This clog can cause sewage to build up inside the pipes, preventing it from entering the sewage system as usual. As the sewage builds up, it decomposes and releases gasses that can seep into your bathroom. The smell is very unpleasant and indicates that you could have potentially harmful bacteria around that could negatively impact your health. A 2015 study published in the National Library of Medicine showed that clogs cause exposure to multi-resistant bacteria, leading to illnesses.

Regular maintenance is key to preventing or unclogging your drains. The best way to unclog your toilet right away is to use a plunger. For stubborn clogs, a drain auger or plumber's snake can get deeper into the pipes and break up or pull out an obstruction. You must use these tools correctly to avoid damaging the pipes or toilets. Setting up a cleaning routine and being careful with what you flush reduces your chances of clogs. Avoid flushing feminine hygiene products, wipes, and excessive toilet paper. Hiring a plumber may be necessary for persistent clogs or if you find yourself unclogging the pipes regularly.

Biofilm is a buildup of microorganisms that stick to pipe surfaces, especially pipes with a lot of moisture and organic matter. This slimy layer comprises fungi and other microbes that embed into the slick, slimy layer. For household plumbing, this biofilm forms on pipes due to the constant supply of organic materials, including grease, food particles, soap scum, and human waste. As this biofilm builds up, it'll eventually decompose and release an unpleasant smell. Worse, the microorganisms can cause pipe corrosion, potential blockages, and lower water flow. Addressing biofilm-related issues is crucial for maintaining a clean and odor-free home environment and ensuring the longevity and efficiency of your plumbing systems.

To fight biofilm formation inside your pipes, use enzymatic drain cleaners for an eco-friendly solution. Experts recommend them for getting pet odors out of the house, but they also have specific enzymatic agents that break down the biofilm's organic components. It'll slowly break down the organic material, disrupt the biofilm's structure, and eliminate the microbial colonies. These are biodegradable, and you can use them in all types of plumbing without causing issues. Apply them according to the instructions on the package to ensure the enzymes have enough time to work on the biofilm and break it down.

Over time, your toilet's components, like the fill valve and flapper, can wear out or break due to material breakdown and regular use. The flapper creates a seal for the toilet tank's drain, and it can lose its integrity. When it does, water will constantly leak from the tank down the bowl. If the fill valve breaks or malfunctions, your toilet tank won't fill with the correct amount of water after each flush. These issues cause you to waste water and increase utility bills, but they can also make the bathroom more humid. A higher humidity level encourages mold and mildew growth, leading to odors. Being constantly wet also makes your other toilet components or the surrounding areas deteriorate faster.

Figuring out which components are faulty and replacing them can be a DIY project that doesn't necessarily require a plumber's help. You can get these parts at your local hardware store, and they have instructions that outline the installation process. The first step is to look at the toilet and determine which part isn't working by checking for constant water flow or listening for water running when you're not using the toilet. Once you narrow down the part, turn off the water supply to the toilet and drain the tank to replace the component safely. Also, there are online tutorials and guides you can follow if you're not sure how to fix the part.