A bad smell in your bathroom is more than just unpleasant. It can be a sign that something is not quite right with your drains, sewer line, toilet, ventilation or plumbing system.
Some bathroom smells are easy to fix yourself, while others can point to a plumbing problem that needs professional attention. If your bathroom constantly smells like sewage, drains or mould, it is worth finding out where the odour is coming from rather than simply covering it up with air freshener.
Here are some of the most common reasons for a bad smell in bathroom areas and what you can do about them.
Why does my bathroom smell bad?
There are several possible causes of a bad smell in your bathroom spaces. The smell itself can often give you a clue about where the problem is coming from.
Common causes include dry floor wastes, blocked basin traps, faulty toilet seals, poor ventilation and partially blocked drains or toilets.
Let’s look at each one.
1. A dry floor waste
One of the most common causes of a bad smell in bathroom areas is a dry floor waste.
Your bathroom floor waste is designed with a water seal that stops sewer gases from travelling back through the drain and into your home. If a bathroom has not been used for some time, the water in this seal can evaporate.
Once the water seal is gone, unpleasant sewer smells can make their way into the bathroom.
You can check your floor waste by shining a torch down the grate. If you can see water, the trap is likely sealed. If you can see straight down into the pipe, the trap may be dry.
To restore the water seal, simply run the shower, bath or basin if it is connected to the floor waste. If the bathroom is rarely used, you can also pour a bucket of water down the floor waste.
If the smell continues after doing this, there could be another plumbing issue that needs to be investigated.
2. A blocked or dirty basin trap
Another common cause of a bad smell in bathroom plumbing is a dirty or partially blocked basin trap.
Over time, toothpaste, hair, soap and other debris can build up inside the basin waste and trap. This creates a place for bacteria to grow, which can result in an unpleasant smell.
If your bathroom basin is draining slowly as well as smelling bad, a blockage could be the cause.
Cleaning the basin plug, waste and trap may solve the problem. However, if the smell returns or the basin continues to drain slowly, you may have a deeper blockage that needs professional attention.
3. A damaged toilet seal
If the smell is strongest around your toilet, a damaged or deteriorated toilet seal could be responsible.
The seal between the toilet pan and the waste pipe helps prevent sewer gases from escaping into your bathroom. Over time, rubber seals can perish or become damaged.
If this happens, you may notice a persistent sewage smell around the base of the toilet.
This is a job for a professional plumber. Replacing the seal generally involves removing the toilet pan, so it is not a repair you should attempt yourself.
If you have a persistent bad smell in the bathroom areas around your toilet, get the problem checked rather than simply trying to mask the smell.
4. Poor bathroom ventilation
Sometimes the source of a bad smell in bathroom areas is not the plumbing at all.
Bathrooms naturally become humid when you shower or bathe. If moisture is not properly removed, it can create the perfect conditions for mould and mildew.
Mould can produce a musty smell and may appear on walls, ceilings, grout, silicone and other surfaces.
Good ventilation can help prevent this. Open a window while showering where possible and use your exhaust fan to remove steam and moisture.
If you have persistent mould, dampness or a musty smell despite good ventilation, there could be a hidden water leak.
A leaking pipe inside a wall or under the floor can allow moisture to build up over time. In this situation, a plumber may need to locate and repair the leak before the mould and smell can be properly addressed.
5. A partially blocked toilet
A partially blocked toilet is another obvious cause of a bad smell in bathroom spaces.
If the toilet is not flushing properly, the water level is unusually high or waste is not clearing completely, there may be a partial blockage in the toilet or drain.
You can try using a toilet plunger to clear a minor blockage. Avoid repeatedly flushing the toilet if the water level is rising, as this could cause an overflow.
If plunging does not solve the problem, it is time to call a plumber.
A professional plumber can use specialised drain cleaning equipment to locate and clear stubborn blockages further down the drainage system.
6. A blocked or damaged drain
If your bathroom smells like sewage even though the toilet and basin appear to be working normally, the problem could be further down the drainage system.
A partially blocked drain can allow organic matter and waste to build up, creating unpleasant odours. Damaged or deteriorating pipes can also contribute to ongoing drainage and sewer problems, as well a plumbing issues.
This is particularly worth investigating if you have an older Sydney home, as ageing plumbing and drainage systems can develop problems over time like tree root ingress or collapsed pipes in your main sewer drain.
If you are also experiencing slow drains, gurgling noises, recurring blockages or water backing up, contact a professional plumber to investigate the cause in your sewer pipe.
How to get rid of a bad smell in bathroom areas
Before calling a plumber, there are a few simple things you can check:
- Run water through rarely used drains.
- Clean your basin plug and waste.
- Check your toilet for obvious leaks or problems.
- Keep the bathroom well ventilated.
- Clean visible mould and mildew.
- Try a suitable toilet plunger if you have a minor blockage.
- Check whether drains are slow or making unusual noises.
If the smell remains after these simple checks, there may be a plumbing issue that needs professional attention.
When should I call a plumber?
A bad smell in bathroom areas does not always mean you need a plumber. However, persistent or recurring odours should not be ignored.
You should consider calling a plumber if:
- Your bathroom smells like sewage.
- The smell keeps returning after cleaning.
- Your toilet is not flushing properly.
- Drains are slow or regularly blocked.
- You hear gurgling from your drains or toilet bowl.
- There is dampness or unexplained mould.
- You suspect a hidden water leak.
- The smell is coming from around the base of your toilet.
- Water is backing up from a floor waste or drain.
A plumber can investigate the source of the smell rather than simply treating the symptoms.
Bad smell in bathroom? GF James Plumbing can help
If you have a bad smell in bathroom areas that will not go away, there could be a problem with your drains, toilet, pipework or ventilation.
Sydney has many older homes with ageing plumbing systems, so recurring smells and drainage problems should be investigated before they become more serious.
At GF James Plumbing, we can help diagnose and resolve plumbing and drainage problems that may be causing unpleasant bathroom odours.
Don’t put up with a bathroom that smells bad every time you walk in. If simple cleaning and ventilation have not solved the problem, contact a professional plumber to find out what is causing the odour.
Got a bad smell in your bathroom that won’t go away? Contact GF James Plumbing today to arrange a professional plumbing inspection.
