Smelly Bathroom Drains in Australian Homes: A Bathtub & Accessories Buying Guide

Nothing ruins a relaxing bath quite like a smelly drain. Drain odours are one of the most common plumbing complaints I hear about, but they're often preventable with the right fixtures and regular maintenance.

Common Causes of Drain Odours

1. The P-Trap Problem

There are bath accessories such as P-trap is usually the place where your drains start to smell bad. That pipe in an S-shape under your bathtubs or basin holds water to create a seal that prevents sewer gases from entering your home. This water seal needs to be maintained.
In Australia's warmer climates, particularly in Queensland and northern regions, water in P-traps can evaporate quickly during hot weather. Go on vacation for a week and come back to discover your bathroom smells like something died. I've seen this happen countless times.

2. Hair and Soap Scum Buildup

Hair, soap scum, body oils and dead skin cells accumulate in bathroom drains over time. This creates a buildup where bacteria can thrive, causing unpleasant odours. In one case I've heard about, the accumulation of hair from a teenage daughter with hair to her waist created a significant blockage that required professional removal.

Choosing the Right Bath Wast

When selecting a bath, it's easy to focus on aesthetics like freestanding designs or spa features. However, the drainage system is equally important for long-term functionality.
When selecting a freestanding bath, ensure your plumber can access the waste connections. This will make future maintenance and repairs more cost-effective.

Install Quality Drain Covers

Install a stainless steel or brass hair strainer over your bath waste. Cheap plastic strainers from discount stores cost around $5-$10 but will break within 12 months. Quality stainless steel options from Reece cost $20-$40 and will last for years, preventing costly blockages.

Consider Bath Material and Installation

Acrylic and fibreglass baths are lighter than cast iron or steel, making installation easier. However, ensure all drain connections are watertight. Small gaps can lead to water leaks, encouraging mould growth, unpleasant odours and potential water damage. I've broken into walls and seen the most monstrous blooms of mould from a waste pipe poorly sealed. 

How to Prevent Drain Odours

Hot Water Flush

Pour hot water (not boiling, as this can damage PVC pipes) down drains weekly to prevent soap scum buildup. Use water from the hot tap instead. Takes two minutes.

Bi-Carb and Vinegar

Pour half a cup of bi-carb soda down the drain, followed by half a cup of vinegar. Let it fizz for 15 minutes, then flush with hot water. This natural, inexpensive method effectively breaks down buildup.

Pop-Up Waste Systems

Pop-up waste systems are easier to maintain than traditional plug-and-chain styles. You can easily remove them for cleaning and check for hair buildup, making regular maintenance simple. Look for pop-up waste systems from Caroma or Phoenix at Reece Plumbing or Bunnings. These brands offer reliable quality and are readily available for parts replacement.

Proper Ventilation

You can't beat installing an exhaust fan in an Australian bathroom, particularly one with water risk. We take the humidity in our climate very seriously. Not enough ventilation means you're creating the ideal conditions for mould, mildew and those nasty drain smells. I've seen bathrooms with condensation running down the walls due to poor ventilation. This creates ideal conditions for mould growth and drain odours.

Professional Installation Requirements

The initial installation is crucial for preventing future drainage problems. Many people don't realize how important correct installation is. A small error in the fall of your waste pipes – just a millimetre or two – can mean water pools rather than runs off. When water pools rather than drains, it becomes stagnant. Bacteria thrives in stagnant water, causing unpleasant odours. Drainage fall must be checked by a licensed plumber before tiling. Incorrect fall is a common cause of ongoing blockages and can only be fixed through costly retiling.
All bath waste installations must comply with Australian plumbing standards. Ensure your plumber provides certification of compliant work, particularly for waterproofing connections.

The Bottom Line

Preventing drain odours starts with proper planning and quality fixtures. Invest in good drain covers, maintain regular cleaning schedules, and ensure proper ventilation. These simple steps will keep your bathroom fresh and prevent costly blockages.
If you've experienced persistent drain odours despite regular maintenance, it's time to call a licensed plumber to check for deeper issues. What other bathroom maintenance tips would you like to know about?