How To Get Rid Of Smelly Floor Drains In Bathroom

Walking into a clean bathroom only to be hit by a foul smell from the floor drain is frustrating, it makes the whole space feel dirty no matter how much you clean. If you’re dealing with a smelly floor drain in your bathroom, you’re definitely not alone. You can fix it, and it doesn’t always require a plumber or a full bathroom renovation.

Let’s explore why your smelly drain on the bathroom floor happens and how you can get rid of it, fast!

What Causes Smelly Drains In Bathroom Floor?

• Dry P-Trap: If you don’t use the drain often, the water in the trap evaporates, letting bad smells rise from the pipes.

   

• Buildup of Gunk: Hair, soap scum, skin cells, and other waste collect over time, creating a stinky mix.

   

• Blocked Vent Pipe: The vent pipe lets sewer gases escape, but if it’s blocked, the smell can back up into your bathroom.

   

• Mould or Mildew: Moisture around the drain can create the perfect place for mildew to grow.

   

• Bacteria: If you’ve ever noticed a rotting or sour smell, that’s often bacteria having a field day down there.

   

Dealing With Sulfur or Sewage Smells

If you notice a sulfur smell—think rotten eggs—coming from your drain or water, it’s a common complaint. Here’s a simple way to pinpoint the culprit:

• Check Other Faucets: If the same smell is coming from multiple faucets around the house, the problem is likely with your water supply itself.
• Isolated Odor: If only one drain smells, your pipes might be contaminated, or you could have venting issues letting sewer gases creep in.

Either way, identifying the source is the first step to freshening up your bathroom.

Is the Smell Coming from Your Water or the Drain?

Noticing a rotten egg (sulfur) smell? It’s a classic complaint, but figuring out whether it’s coming from your water supply or the actual drain is surprisingly easy.

Here’s a quick way to tell:

• Test Other Taps: Run water in a sink or tub in a different room. If the smell shows up everywhere, your water supply might be the culprit—possibly due to bacteria in the hot water heater or issues with city water.
• Sniff Test at the Drain: If only your bathroom floor drain is smelly, even when water isn’t running, it’s more likely a drain or vent problem. This means there could be gunk, bacteria, or even a blocked vent pipe making your bathroom air less than fresh.

If the odor’s just at one location, your pipes or drain are probably to blame. On the other hand, if every tap in the house triggers that stench, it’s time to check what’s going on with your water source.

Could Hard Water Be the Culprit Behind That Sulfur Smell?

If you’re picking up on a distinctive rotten egg or sulfur smell in your bathroom, don’t be too quick to blame last night’s curry. One sneaky cause is actually your water supply—specifically, hard water without proper filtration.

Hard water contains higher levels of minerals like calcium and magnesium. Sometimes, those minerals react with naturally occurring bacteria in your plumbing, creating hydrogen sulfide gas. That’s the classic sulfur smell you’re noticing. If your house doesn’t use a water softener (think Brita filters, Kinetico, or Culligan systems), these minerals can build up and make odors worse.

Quick check:

• Is the sulfur smell coming from every bathroom or faucet in your home? It might be a problem with your water supply, not just the bathroom drains.
• But if the smell is only from the bathroom floor drain, chances are it’s a local plumbing or venting issue.

If you suspect hard water is at fault, installing a water softener or a filtration system can help remove those odor-causing minerals. Not only does it fight smells, but it’s also a win for your skin, hair, and plumbing appliances.

Now that you know why it stinks, let’s see what you can do to fix your smelly floor drains in the bathroom once and for all.

Now that you know why it stinks, let’s see what you can do to fix your smelly floor drains in the bathroom once and for all.

1. Pour Boiling Water Down the Drain

Start simple. Boiling water can loosen buildup and flush away bacteria causing the smell. Just carefully pour a full kettle of hot water down the smelly drain on the bathroom floor and see if it helps.

Repeat this once a week to keep things fresh.

2. Use Baking Soda and Vinegar

This is a safe, natural way to fight bad smells.

Steps:

1. Pour ½ cup of baking soda down the drain.
2. Follow with 1 cup of white vinegar.
3. Let it bubble for 10–15 minutes.
4. Rinse it all down with hot water.

This combo breaks down grime and deodorises your smelly floor drain in the bathroom without harsh chemicals.

Will Just Baking Soda Keep Bathroom Drains Smelling Fresh?

Sprinkling baking soda down the drain every so often can definitely help in the battle against bathroom drain odours. Think of it as a gentle deodoriser—it neutralises mild smells and helps stop grime from building up in the first place.

However, baking soda by itself isn’t a magic bullet. For stubborn smells or heavy buildup, you’ll get the best results by pairing baking soda with vinegar and following up with a hot water rinse. Regular use does help prevent odours from creeping back, so it’s a handy habit to add to your cleaning routine.

Lemon Juice and Baking Soda Method

Looking for another natural way to tackle a stubborn bathroom floor drain smell? Try lemon juice and baking soda. The fizzing action not only helps break down grime but also leaves behind a fresh, citrusy scent.

Here’s how to use it:

1. Sprinkle about half a cup of baking soda down your floor drain.
2. Pour half a cup of fresh lemon juice over the baking soda.
3. Let the mixture bubble and fizz for 10–15 minutes—this helps loosen debris and knock out odors.
4. Rinse everything through with hot water.

Not only is this method gentle on your pipes, but it’s also great if you want your bathroom smelling bright and clean without harsh chemicals.

3. Clean the Drain Cover and Surroundings

Sometimes the smell isn’t just inside the drain. Remove the cover and clean around it. Use an old toothbrush with dish soap or vinegar to scrub away slime and dirt.

This step is especially useful if you’ve noticed a musty smell or visible gunk near the smelly drain in the bathroom floor.

4. Refill the P-Trap

If your floor drain doesn’t get much use, it may be dry. This is a common reason for smelly floor drains in the bathroom, especially in guest bathrooms or laundry areas.

To fix this:

• Pour a bucket of water down the drain.
• Add a tablespoon of cooking oil, it forms a thin layer that slows down evaporation.

5. Try a Drain Snake or Wire

Hair and soap scum often build up deeper in the drain. A drain snake or even a bent wire hanger can help you pull out the gunk.

Be sure to wear gloves, it can get messy, but it’s satisfying to know you’ve cleared your smelly drain in the bathroom floor at the root.

Can Plunging the Toilet Help with Drain Smells?

It might sound odd, but sometimes giving your toilet a good plunge can actually help clear unpleasant smells from your bathroom floor drain. Here’s why: if there’s a partial blockage further down your waste line, it can mess with how air and water flow, letting sewer gas sneak up through your drains.

Using a plunger creates pressure and can help dislodge any hidden blockages in the pipes that connect your toilet and floor drain. Just remember:

• Make sure the plunger forms a tight seal.
• Use firm, steady force.
• Don’t forget your gloves (for obvious reasons!).

If plunging helps, it’s a sign that a blockage might have been contributing to the lingering smells from your bathroom drain.

6. Use an Enzyme Cleaner

Enzyme drain cleaners are great because they eat away organic buildup (like hair, soap, and grime) without damaging your pipes.

Look for one at your local hardware store and follow the instructions. Use it monthly to prevent smelly floor drains in the bathroom in the future.

7. Check for Venting Issues

If you’ve tried everything and the smell still comes back, there might be a problem with the vent pipe. This part of the plumbing lets sewer gas escape outside. When it’s blocked, that gas ends up in your bathroom.

This is the point where you’ll want a professional plumber to step in.

Don’t Let Bad Smells Take Over Your Bathroom

Smells from the bathroom drain aren’t just gross, they’re a sign that something needs attention. Whether it’s a dry trap, buildup, or something deeper, you’ve now got a full list of ways to take control and say goodbye to that smelly floor drain in the bathroom.

If the smell keeps coming back or you’re not sure where to start, don’t stress. Ready Set Plumb is here to help Sydney locals tackle drains in the bathroom with fast, reliable solutions.

Fix your smelly floor drains