Mon - Sun: 24/7 Plumbing
4.7 Star Service


(03) 9909 5128

A bathroom is a place where you relax and rejuvenate.

Sweet fragrances have a positive impact on our minds and help us unwind while taking a bath. Studies show that people who take aromatherapy and relaxing baths have much lower stress levels than those who don’t.

But it can all go downhill if you have leaky and smelly drains. They just ruin the clean and cozy vibe of a bathroom and make it extremely uncomfortable to use. So, you need to look out for these dirty smells and get rid of them as soon as possible.

Foul-smelling bathroom drains shouldn’t be taken lightly because they might be a symptom of some underlying drainage problem. In today’s guide, we will discuss effective ways to stop your drains from smelling.

Why Do Bathroom Drains Get Smelly? 

Before we move on to treating the smelly drains, let’s have a look at the reasons behind the problem. It is much more effective to find solutions after learning the root cause of the issue. 

Bathroom drains can stink for a number of reasons, and a few of them are:

1. Mould Growth

Try smelling around your drains in your bathroom. We know it’ll be gross, but you’ll have to bear with it if you want to get to the heart of the situation. If you smell a musty odour, chances are mould is growing actively in your pipes.

Mould colonies produce spores that keep releasing tiny gaseous puffs with a characteristic musty smell. This stink can take a toll on your health if inhaled directly, causing nausea, dizziness, and headache.

2. Biofilm Formation

A biofilm is a layer of accumulated debris, non-biodegradable clogging and pathogenic growth. Bacterial colonies release sticky glue-like mucilaginous fluids that serve as an adhesive between the debris and drains.

You can test the presence of a biofilm by running your shower water for two to three minutes. Notice whether the flow of water is fine or it is low pressure because if the water comes out with less pressure, your drain might be clogged.

Also, the smell produced by such biological clogging is usually like rotten eggs. Such a build-up of pathogens and decomposing debris can become a breeding spot for several waterborne diseases. That’s why you shouldn’t take smelly drains lightly.

3. Sewer Gases

If your taps are working just fine and there is no change in the water flow and pressure, you may still be able to sense that rotten egg stink. This happens when sewer gases escape from the pipelines.

Also known as hydrogen sulphide, these gases point towards the possibility of blockages or damage in your drainage system. The amount of sewer gas, aka hydrogen sulphide that escapes from drains, doesn’t impact the health but makes the living space uncomfortable.

Drains usually have a structure called a P-trap that serves as a barrier between air and water being transported through the drains. The gases might be able to enter the drainage system due to a broken or absent P-trap. 

Additionally, sewer backup or trouble in the mainline might contribute to the problem too.

4. Clogged Air Vents

Drains are designed to prevent sewer gases and air from entering the network and have a system of vents in place. These vents are interconnected with all the drains of the house and open on the terrace. 

Moreover, they carry all the air and release them through the opening. If the air vents or the grates at their opening get clogged due to dust and debris, the gases can enter the drain system, causing them to gurgle and give off a musty smell. 

Hence, it is important to get the vents tested every once in a while.

How To Fix Smelly Bathroom Drains?

We discussed the main reason that can lead to smelly bathroom drains. We’ll now proceed to the fixing part, so keep reading to find out.

1. Cleaning The Mould

First of all, try and have a close look at the mould growth. 

For getting rid of the mould, you’ll need three ingredients that are easily available at home, along with one simple tool. Get some baking soda and white vinegar from the kitchen, and boil some water. Then, grab an old toothbrush, and you’re ready to begin cleaning.

Mix equal parts of normal water and baking soda to create a paste. When the paste becomes somewhat viscous and adopts a slightly thicker consistency, apply it on the stinky drain using a toothbrush. Once you’re happy with the application, sit it out for ten minutes before scrubbing the drain.

You must note that when the mould is visibly growing around the drain, things can get really ugly. Keep scrubbing until the growth loosens and you are satisfied with the result. 

Next, boil around ten quarts of water and let it cool off a little. If you have PVC (Poly Vinyl Chloride) drains, then boiling water can damage it by melting, so we advise keeping the water at 145 to 150 degrees Celsius. This temperature range is ideal for killing mould. 

Once the water is at an appropriate temperature, pour it down the drain slowly and steadily. Additionally, pour a cup of vinegar and half a cup of baking soda too. This will likely kill the mould and rid your drains of the foul smell.

2. Clearing Drain Clogs

You can clean small drain blockages easily on your own by following a few simple steps. You will need to first identify where the clog is and then you will need a drain brush cleaner, baking soda, some white distilled vinegar, and boiling water for this method.

First and foremost, remove the drain cover or grate using a screwdriver. If you have a push and pull drain, unscrew it by rotating it counter-clockwise. Also, keep some boiled water handy ( five to ten quarts) and pour it down the drain gently. 

The water will make the clog moist, and once that is done, pour a cup of distilled white vinegar into the smelly drain. Shove down half a cup of baking soda immediately after the vinegar, following which you’ll have to wait for two hours before the next step.

After the waiting period is over, pour around a gallon of lukewarm water into the drain. All this was preparatory work, making the blockage susceptible before the actual cleaning.

Now, the most important part is to clear the clog and remove the debris using a drain brush. Do it carefully and thoroughly, loosening and removing all the accumulated matter (the biofilm, as discussed earlier).

Most probably, the blockage will be cleared, and your drain will stop smelling. If the smell still doesn’t leave or comes back after a while, you’ll have to call a plumber to help you out.

3. Fix The P-Trap

The P-Trap uses a layer of water to keep the gases separate from the water supply in drains. If that water barrier dries up, your drains can gurgle and smell. 

Flash a torch down your bathroom drain; if you can see water there, then your drain hasn’t dried, and there is some other reason behind the smell. You’ll possibly have to call a professional for an inspection. But if the P-Trap has dried, then no worries, we’ll tell you how to fix it. 

Trust us, the process is straightforward, and you simply need to pour one to two cups of water into your drain. Wait for an hour, and check again.

If the water level stays intact, then your problem has been solved. What’s more, add four ounces of cooking or mineral oil into the P-trap to slow down the water evaporation and keep the curved pipe moist.

4. Install A Hair Catcher

Hair trapping is a massive cause of drain clogging and foul odour. It might appear negligible at first, but the issue is much more prevalent than you think. 

We have fine hair all over our bodies which sheds and goes down the drain whenever we bathe or wash. All this hair can accumulate and cause big drainage problems. 

Luckily, hair catchers are affordable and very easy to install. We suggest going for them instead of paying hefty plumbing fees.

Fixing Your Smelly Bathroom Drain

Alright, folks, that’s about it for this guide; you should have got some clarity on why bathroom drains stink and how to fix them. 

Before signing off, let’s go over the gist of the matter once again. Because of mould, mildew, blockages, and sewer gases, drains can get smelly. But you can fix these problems on your own with a bit of cleaning by using baking soda, white vinegar and boiled water.

We will be signing off on that note. Until next time! Take care.

How Does Pipe Relining Work?

How Does Pipe Relining Work?

Wondering how pipe relining works to restore the proper functioning of any plumbing system? We break it down for you through this extensive guide on the topic.

Blocked Drains: What Are The Warning Signs What You Need To Know?

Blocked Drains: What Are The Warning Signs What You Need To Know?

Many different things can cause blocked drains such as hair, gunk, and debris and can become more severe over time if not dealt with immediately. These are the Warning signs of drain blockages to look out for.

Why Is My Drain Overflowing?

Why Is My Drain Overflowing?

An overflowing drain in your house can be a nightmare. If you want to know the possible causes and the best solutions to overflowing drains join us on our guide!

WP Plumbing Van
Call Now!