House Smells like Sewage- Get Rid of sewer gas smell & Eliminate Odor with these Simple Tricks12 min read

House Smells like Sewage- Get Rid of sewer gas smell & Eliminate Odor with these Simple Tricks12 min read

Does your house smells like sewage? No one like to breath foul odor. In fact, if you have a leak in the house, you will be okay to live with it until you plumber shows up. But, the noxious odor – grrr!.

When your house smells a bad odor – like sewage – it’s leaking gas. The main reason for the foul odor is due to a leak from one of the drain plumbing line of the sewer system.  Find the spot where gas leaks and address that issue; you will be fine.

As you know there are many reasons why you feel musty or sewer smell in the house.  I know you are eager to know how to get rid of bad smells in your house.

Because you can’t tolerate it.  But, remember that should be the second reason why you should fix the issue.

Sewer gas has hydrogen sulfide in it which smells like rotten egg.

Check this:

Hydrogen sulfide is a flammable and colorless toxic gas thst smells. Not just that – it is extremely dangerous for human health when inhaled.

Can Breathing Sewer Gas Make You Sick?

Absolutely. Without an iota of doubt.

Your ability to smell gas is a boon.  Run and fix it immediately.

Now if you get the smell on and off and in low dosage, you might be tempted to spray air freshener and get by.

Don’t skimp here.

Depending on any level of dosage of inhaling sewer gas, you are likely to have health issues.

Sewer gas affects your health in different ways based on the below two factors

  • Amount of Dosage and
  • Longevity of Exposure

With low intensity and limited exposure, someone might have irritation. Other side effects might take time to show up. With long exposure and high dosage, someone might feel the hit instantly.  It can even lead to coma and death in certain circumstances.

Sewer gas is dangerous at any level and at any amount of intensity and exposure.

Don’t try to work around this issue. As it can cause headaches, irritability, headaches, sinus infections, fatigue, bronchitis, loss of appetite, pneumonia, memory loss, dizziness, and the list goes on…

…even at low levels.

I am not scaring you, but that’s the truth.

Want to know more about sewer gas and specifically about hydrogen sulfide – check this quick card from OSHA to learn more.

4 Top Reason Why You are Getting a Foul Odor

1.      Dried P-Trap:

Well, that’s the U-like fitting that is underneath any sink you see in your house.

But, you also have the same thing under any drain (most of them)

That means…

… it is also under your shower and tub.

P-trap is designed and is per code for a reason.  P-Trap has a stagnant water in there.

Well, the trapped water is the one that is holding the sewer gas from traveling back and into the house.

What happens when you don’t have water standing in the P-Trap? What happens when the water dries in the P-Trap.

You guessed it right.

Sewer gas comes off and you get that nasty smell.

2.     Cracked Venting System

You might have a hole in one of your venting systems somewhere, that is leaking gas inside your house.

Instead of venting up the rooftop.

You might have a pipe that is broken somewhere. Underneath the slab or in your crawl space, there might be a leak.

That pipe drips the sewer water that gets absorbed by the soil, but somehow the odor gets to you.

3.     Wax Seal Issue

If you wax seal is cracked or not setup properly that is going to leak the gas out, which will make it uncomfortable. Any gap in your toilet is going to leak the gas.

Make sure to wiggle all your toilet bowl to make sure it’s tight and not moving.

4.     Uncleaned Septic Tank

If you are on Septic and if it’s not cleaned properly, that gas will come back up and will make its way.

There are other environmental reasons that put a pressure in the tank and if the gas has nowhere to go, then your house is where it ends up.

What Does Sewer Gas Smell Like?

Well, this is a question that is best answered with another question.

How does a rotten egg smell?

If you can relate to that, then you know the smell of sewer gas.

Like I mentioned earlier, it is the smell of hydrogen sulfide.  And it smells like rotten eggs.


There is not enough awareness around on this subject and I want to make it clear.

You may lose the ability to smell sewer gas if you are exposed to a length of time.

That is, even if you have a high dosage of gas, you may not be able to identify.

Once you lost the ability, you may not be able to detect.

So, my advice is to fix it immediately when you smell the sewer gas the very first time.

If you are not sure you may use the sewer gas detector.

Shower Drain Smells Like Sewer

Everyone like freshness when you’re done showering – not an unpleasant smell.

Unlike some of the other spots in the house, shower drain smell might be the simplest to elimate.

There can only be 2 major issues in a shower drain line

Biofilm Buildup

This is by far the biggest problem in the shower.

What happens is this.

When you shower you use soaps, shampoo, conditioner, and such.

Your body contributes a few too.  Dead cells, body oil, dirt, and grime.

As times goes by, all these combined will form layers in your pipes and P-Trap.  The build-up is called the biofilm.

Now, you have some organic material deposited and eventually as they break down due to microorganisms, it starts to give an odor in the bathroom.Cleaning Bio film buildup will stop sewer smell in bathroom

Keeping the bathroom clean and clutter-free doesn’t help only with the smell, but also make the bathroom looks bigger.  Check this making a small bathroom bigger blog post to learn more.

Clogged P-Trap with Biofilm Deposits

Pop-Quiz: Do you know the biggest clog in the shower P-Trap?

Hair.  Now, combine all that I said earlier and add hair to the mix.  It makes the problem even worse

The biofilm will coat over each hair and since there is enough mesh the biofilm accumulation gets accelerated.

Don’t worry, Cleaning that is very easy.

Remove the drain cover and start pulling the hair deposits.

Cleaning the biofilm isn’t bad either. Just cleaning liquid and some agitation will do the trick.

If you don’t use the shower for an extended period, your P-Trap might become dry causing the issue.

If that’s the case…

…Wait, are you not taking a shower at all? Well, then YOU are probably smelling and not the shower.

Just kidding.  I know you have this spare guest bedroom shower that you don’t use.

In any case, for dried P-Trap, just run some water and a spoon of oil and you will kill the smell instantly.

Toilet Smells Like Sewage When Flushed

Are you getting the unpleasant smell particularly when you flush the toilet?

This is caused by simple physics if none of the other reason mentioned here apply.

Every plumbing fixture, including toilet, is connected to a drain pipe.  All these drain pipes are further connected to the main sewer that connects to the municipality line.

There is a problem, however, doing this way.

For water to go freely, you need something else to replace what’s lost in the system.

You have air in the pipes, and when you flush the toilet, for the water to run freely, the air needs to be displaced.

So, plumbers add vent pipes to most fixtures.  Now, these vent pipes are further connected to the main one that goes up the roof.

Essentially, water goes down smoothly, pushing air up the vent pipe through the roof. And if it needs more air, it even sucks air through the same vent pipe.

Keeping the pressure inside the pipe closer to the atmospheric pressure.  So no negative or positive pressure builds up in the system.

What happens is if you have a clog somewhere you are building up the pressure in the pipes and gas must be relieved somewhere. That might your bathroom.

I have a couple of fixtures where the plumber slacked big time adding no vent pipe.  I constantly run into issues where the water flow becomes excruciatingly slow.

Luckily that’s a vanity so it is only water going down that drain line.

Now, if that was done to a toilet fixture, it will sure to off-gas into the bathroom.

Yard Smells Like Sewer After Rain

Well, this is an issue with both residential and municipal sewer system.

The section below will touch on residential – septic tank – related off-gassing issues when it rains.

Pressure build-up

When it rains water tend to run to the lowest point taking all the space up.  Now, this causes gas to be pressurized.

The result of which is the unpleasant odor in the yard.

Water Back-Up

When it rains, if your city cannot handle the load then the sewer systems starts backing up.

Well, if you don’t have a backflow trap setup, you might even have some of those sewers coming out of your basement drain.

If you have an access in your yard (for cleanout) some backup pressure can cause the gas to leak off of it.

Generally, if your city is sitting on an older system that is not maintained well, there might be a lot of spots where sewer might be overflowing.

If you think it smells like sewage outside the house, you just found the reason.

Septic Tank Smells Like Sewage

There are several reasons for this. However, the main one is

Heavier Air:

When the air is heavy due to rain, then the methane gas has no place to go off the vent.  This will cause the smell of rotten egg at other spots.

House Smells Like Sewer When It Rains

Septic tanks can have lagoons or leach fields.  Leach field is common is regular residential setup.

When it rains the ground gets saturated with water.  Leach field is set up so the extra wastewater from the septic tank can be leached off.

Now that will be affected with continuous rain.  So, the liquid in the tank increases.

All this creates an extra pressure in the septic system and the methane gas is pressurized and wants to escape where it can.

If you have an unused bathroom, water may have dried, causing the pressure to be relieved.

The easiest solution is to flush all toiled every couple of months and run water in

How to Eliminate Sewer Odor

What do you like to know?

Quickest, cheapest and temporary solution….

Or… The easiest, safest and permanent solution?

I guessed you opted for the latter. Smart!

I will provide both the answers, regardless.

Quickest, cheapest and temporary solution

  1. Open the window and spray air freshener.

If you issue is a short onetime happening, then opening the window and spraying air freshener will do.

But if you continue to get the smell, then try other measures provided below.

  1. Just add water to the P-Trap.

If it’s a dried P-Trap situation, due to non-use for a length of time, then lack of water in the P-Trap is causing the gas to leak.

Just add water down the drain and let the hot water run down the drain for a few minutes and this will solve.

For both the above, give it a few hours and see if you still have the noxious smell.

  1. Apply the DIY smell remover

Pour a half a cup of baking soda into the drain and then follow it by vinegar.  After about a couple of hours pour hot water down the drain.

Then give it a good fifteen minutes and run cold water for about ten minutes so it is all washed out of the system.

Optionally, you can add half a cup of chlorine bleach into the drain and let it marinate for two hours.  Wash it by running cold water for 10 minutes.

P-Trap should have enough water. If you think you are not going to use it for a while, just add a few spoons of oil, which slows the evaporation of water from P-Trap.

Warning: Don’t mix chlorine and vinegar, else you will have another type of toxic gas. Lol 😉

Try these quick ones and see if it solves simple problems.

If you still have the smell either call a plumber or take extra measures.

Easiest, safest and permanent solution

  1. Reset the toilet

If you have cracked flange or worn our rings or if the toilet is not setup tight, then it’s simple problem to fix.

Install a wax ring, set the toilet up and tighten it.

  1. Sewer solar ventilation system

If you have a hairline crack or something that’s too hard to notice, go up the roof and add a solar sewer ventilation system to the vent pipes.

What it does is this:

It runs non-stop due to solar energy supply and runs all the time.  It extracts and pulls all the remaining sewer gas in the system and out.

It’s an excellent option if you can’t identify the issue.

  1. Call a plumber

Let the experts use the cameras to locate the issue by running cameras into the sewer pipe.

They may also use candles to do some smoke test and most importantly use their skill and knowledge to get rid of the foul odor.


It feels like rotten egg and no one likes to breathe, eat or sleep with that smell around.

Getting rid of it is usually pretty easy.

You can follow the simple three-step process before calling a plumber.

Run water at all the drain spots, change the toilet rings and pour in the DIY cleaning solution.

If you are not successful with any of these, try to add a solar vent exhaust fan in the roof vent.  If you can’t identify or fix, there is always your plumber.

In any case, the sewer gas is not good for your health, so act on it and get rid of it permanently.

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