Sewage Smell in Bathroom

The sewage smell in the bathroom is highly unattractive. You enter your room. It’s all fragrant, and when you open the bathroom door, BOOM! The sewer smell attack.

The leading causes of sewage smell are dry P-Trap, clogged drains, plumbing pipe leakage, and improper cleaning. It’s not that big of an issue though, because the problem is pretty solvable.

The important thing is to pinpoint where the smell is coming from, which is not always as easy as it sounds because then you can only begin the ‘solution’ journey.

If you’ve been smelling a weird odor in your bathroom and you don’t know where it’s coming from, here are some ways to locate the spot.

How to Identify the Sewer Smelling Area in Your Bathroom?

If you’re wondering why bathroom sinks smell like sewage, you’ll have to get to the roots of the problem.

Your bathroom includes your plumbing area, drains, sinks or bathtubs, so it’s not always a piece of cake to identify where the problem is rising from.

First off, we can detect the smelly area by observing each part that we’re doubtful about but if it turns out to be a waste of time or the smell is too strong, you can always reach out to experts who offer the cleaning services.

Let’s begin with the handy and practical tips to identify the flawed area quickly. The sooner you find them, the quicker it is to fix them. Here’s how you can work on it.

Check Your Drains

The first part of the bathroom will have your attention when you smell the rotten egg odor in your drains, and that’s quite reasonable because they’re home to many bacteria.

It may be your toilet drain, bathtub drain, or sink drain. All of them need regular cleaning, which offers an excellent unclogging.

You can easily do it at home, but don’t wait to call a professional because the lingering smell is not good for your health if the problem is severe.

If you don’t want to do it by yourself, you can use various tools to suit the cleaning purpose.

Check Your Plumbing

Another main aspect of the sewer gas smell in the bathroom is plumbing pipe leakage or blockage.

There are 2 reasons for the bad condition of the plumbing pipes: Sometimes the pipes get rough with time, other times its bacteria clogging them with little to no space for water travel.

For this matter, you can check the sink plumbing pipes, particularly P-Trap, that helps your pipes stay unclogged by airing them adequately. If you find the problem there, try fixing it yourself or contact a licensed plumber and save a stitch in time to save the following nine.

Go for a Smoke Test

The smoking test is among the most accurate smoke leaking identifiers. It works with a smoke blower tool, and the plumber uses a smoke candle to locate the leaking pipes.

It’s just a matter of 5 minutes (or less if you’re not working solo). The plumbers fix the smoke candles in the smoke blower candle socket and link the smoke blower’s pipes to the main pipe of your bathroom.

As the candle is lit, the smoke is blown into your drain pipes, and it comes out from the leaking or damaged pipes in the bathroom.

It’s as easy as that. Once the issue is identified, the fixing process can start right away to counter the bad smell in the place. It can begin with mending the pipes or, worse, replacing them with new ones, which can cost you a good hundred bucks.

We’re done with the first challenge, and now we know where the smell was coming from. Let us move to the causes that make your bathroom stinky.

Main Causes for the Bad Odor in Your Bathroom

When your bathroom smells terrible, it’s practically asking for your attention. What’s the most brilliant move in such a case? To act immediately!

The sewer smell in the bathroom keeps getting stronger if the problem is not addressed in time. The main smell in sewer gas is Hydrogen Sulfide which is detrimental to your and your family’s health. Constant exposure to this gas can even cause death.

Other gases like ammonia, methane, and carbon dioxide are equally hazardous, and the only way you can prevent the sewer gas from lingering in the bathroom is by being careful about it from the start.

Here’s what causes the sewage smell in your bathroom. Keep these spots in regular check to stop the problem from escalating.

Drain Bacteria Accumulation

One of the main reasons for the sewage smell is the drain bacteria. We use several products for a perfect shower or bath, including shampoos, body gels, or soaps.

When we rinse them without running water through the drains, the bacteria (biofilm) that we wash off sticks to our draining pipes.

The continuous accumulation of biofilm thins the pipes, which restricts water flow, and your drains clog.

Broken Seals

Our toilet bowls are connected to the drain pipes through a strong seal, so the water flows without any cutbacks.

How do broken seals play their part? When the toilet seals get damaged or broken, the toilet water leaks on the floor, giving the floor stains and smelly water.

So next time you question why the bathroom smells like urine, know that a leaking wax ring contributes and accumulates to sewer gases in your bathroom.

Dry P-Trap

If you’re reading this, you probably know where the P-Trap pipe is, but if not, get to your sink plumbing area, and you’ll see a ‘P’ shaped pipe. That’s what we call P-Trap.

The actual purpose of the P-Trap pipe is to keep the ventilation open for passing water, so it doesn’t get dried and take air from other sides.

Besides this, the U-shaped pipe also keeps some water on hold to block the sewer gases from reaching the bathroom through pipes. When the pipe gets dry, it becomes a gateway for sewage smell or gases.

Blocked Drains

Drain blocking or clogging is a common issue in our households. It’s most likely when a solid blocks the water’s way.

What happens with the blocked drain is there’s no water supply, and the sewer gases make their way to your bathroom through the clogged plumbing pipes.

The blocked drains can give your entire bathroom a foul odor which can be stubborn when it’s time to leave. Whether it’s your sink or your toilet, or the shower drain, it can happen anywhere.

These are the 4 main reasons your bathroom has that weird smell, causing your nausea, headache, or whatnot.

How to keep yourself and your bathroom out of the situation? By following preventive measures.

Related >> Why Does My House Smell Like Paint?

Effective Ways to Solve Sewer Gas Issues in Your Bathroom

So you smelt sewer gas in your bathroom. You located the leaking point, and you found out the reasons why it happened. Now it’s time to solve the issue.

When our bathrooms smell like sewage, it’s best to solve the problem as soon as possible. Because the sewer smell issues aren’t addressed in time, they can give birth to bigger problems, mainly health dangers.

Let’s delve into the details.

Get Rid of Drain Bacteria

Your bathroom drain bacteria need quick cleaning because it’s probably the first and main reason why your bathroom smells like sewer.

You can begin with draining hot water (not boiling) down the drain. After that, use the ready-made mixtures that you bought from your local supermarket or make a DIY mixture yourself by mixing equal amounts of salt, baking soda, and vinegar.

How to:

Remove the drain lid, pour hot water into it.

Pour down your cleaning solution and let it sit. (If it’s chemical-based, 30 minutes are enough. Otherwise, leave it for a couple of hours)

Drain more water

Cover the drain.

This will be a good way to almost instantly solve the smell issues, but if the problem persists, please call a plumber for a permanent and professional solution. Besides that, make the drain cleaning a practice every once a week.

Fix Wax Seals

Wax rings are the endpoints joining your toilet to the bathroom drain pipe. They often get damaged and cause water leakage, which we’ve discussed above.

Once you’ve figured out the problem-causing points, start working for its fix. How? Either by pasting the ring with more caulk.


Drain water down the toilet

Cut toilet’s access to pipes

If the wax ring is loose, reposition it and apply caulk

If it seems broken, replace the old one with new

The wax ring problem is easy to solve if it’s limited to the leakage only, but in case your bathroom is broken, you’ll need professional help.

Unclog the Drains

When we are washing dishes, some solid particles of food in the drain block the water’s way to the plumbing pipes.

Whatever it is, you’ll have to draw out the sewer smell using available methods. This way, you’ll be able to resolve the small issues before they spread throughout the house.


Pour down boiling water

Use a drain snake to unclog the drain

Pour cleaning mixture

Leave it for a while

If your drain has some serious clogging issues, you can use a wire-shaped as a hook and unclog the drain by taking out whatever is stuck in there. If it still doesn’t work, you know what to do.

Fixing Dry P-Traps

Now that you know how vital P-Trap’s function is for saving your bathroom from sewer smell let’s get to the fixing method.

The easiest way to fix a dry P-Trap is by running a good amount of water through its drains. The period can be anywhere around 5 to 10 minutes.

That’s about it! There are no complicated ‘how-tos’ here.

Running some water will be enough if it’s really your P-Trap issue, but the problem can be serious if this doesn’t work.

Tips to Avoid Sewer Gas Smell In Bathrooms

We’ve heard people talking about how the solution lies in the very problem, but we’re in panic most times and can’t see how the quote relates to us.

If we’re always careful with our practices, there are negligible chances for any sort of smelling problems. With a little attention to proper cleaning, there will be no need to look for solutions for the problems that you can easily avoid.

  1. Whenever you put the sink’s tab on, leave the hot water flowing for a minute. It’ll pass out the bacteria staying in the pipes.
  2. Use tools to clean the drains regularly.
  3. When the drains get blocked, unclog them immediately. If you wait, there are chances that the thing slips out of your mind completely.
  4. Regularly check on all the Traps in your house. Maintain the water needed there, so they don’t dry out.
  5. Pay attention to the toilet. If it’s leaking or got broken, ask a professional for a reliable solution that will keep you at peace for the longest possible time.

These 5 tips, if you follow, are enough to keep you out of the last-minute hassle of solving bathroom smelling issues.


Bathrooms smelling like sewers may seem like a temporary problem, but it can really be a big problem if not treated at the right time.

The bad smell in the bathroom does not only disgust you, but it also attacks your health. It’s embarrassing in front of guests.

The stress of the blog is on the ‘early treatment’ of sewer smell because the smell takes its time before it finally vanishes.

Share through the comments how you clean your bathroom or deal with the persistent issues like sewer smell in the place. It may help other people who are looking for a functional solution.

by Lisa Wilson

Without the internet, Lisa would never have discovered upcycling. She used wisdom from other people’s blogs to begin her upcycling journey, then she started writing her own!