Common Plumbing Myths Debunked
There is no shortage of plumbing myths in Australia, and believing the wrong ones can cost you real money. From well-meaning advice passed down by relatives to questionable tips found online, misinformation about plumbing leads to damaged pipes, wasted water, and expensive repair bills every year. We have been fixing the consequences of these myths for over a decade, so let us set the record straight.
Myth 1: Chemical Drain Cleaners Are Safe and Effective
The Myth
Liquid drain cleaners from the supermarket are the best way to clear a blockage.
The Reality
Chemical drain cleaners are one of the worst things you can pour down your pipes. The harsh chemicals -- typically sodium hydroxide or sulphuric acid -- generate intense heat as they react, which can soften and warp PVC pipes and corrode older metal plumbing. They rarely clear the full blockage either. Instead, they often dissolve a small channel through the obstruction, giving you temporary relief whilst the underlying problem grows worse.
Even more concerning, these chemicals create toxic fumes that linger in your bathroom or kitchen, and they make the pipe dangerous for any plumber who later needs to work on it. If you have a blocked drain, a plunger, drain snake, or professional hydro-jetting service will always be more effective and safer for your plumbing.
Myth 2: Running Water Helps Grease Go Down the Drain
The Myth
If you run hot water whilst pouring grease or oil down the drain, it will flush through without any problems.
The Reality
Hot water may keep grease liquid while it is in your sink, but it cools quickly as it travels through your pipes. Within a metre or two, that grease solidifies and sticks to pipe walls. Over time, layer upon layer builds up until you have a serious blockage that no amount of hot water will shift.
The proper way to dispose of cooking grease is to let it cool and solidify, then scrape it into the bin. For larger quantities of oil, pour it into a container and dispose of it at your local recycling centre. Your drains will thank you.
Myth 3: A Dripping Tap Is Just a Minor Annoyance
The Myth
A slowly dripping tap is not worth worrying about until it gets worse.
The Reality
A single tap dripping once per second wastes more than 11,000 litres of water per year. At current Sydney Water rates, that is roughly $25 to $35 per year per tap -- and most homes with one dripping tap have others. Beyond the water bill, a persistent drip can stain sinks and basins, and the constant moisture encourages mould growth.
The fix is usually straightforward. A worn washer or cartridge replacement is a quick, inexpensive job for a licensed plumber. The longer you leave it, the more likely the tap seat will become damaged, turning a simple repair into a full tap replacement.
Myth 4: Flushable Wipes Are Safe for Toilets
The Myth
If the packet says "flushable," it must be safe to flush.
The Reality
Despite their marketing, flushable wipes do not break down like toilet paper. They hold together far longer in your plumbing system, snagging on joints and rough spots inside your pipes. Over time, they combine with grease and other debris to form solid blockages -- what the water industry calls "fatbergs."
Sydney Water spends millions each year clearing wipe-related blockages from the sewer network, and the problem starts in household pipes. The only things that should be flushed are human waste and toilet paper. Everything else goes in the bin.
Myth 5: Bricks in Toilet Tanks Save Water
The Myth
Placing a brick in your toilet cistern reduces water consumption.
The Reality
This old trick might reduce the volume of water per flush slightly, but it causes more problems than it solves. Bricks gradually disintegrate in water, and the loose fragments can jam the flush valve, damage the seal, and clog the outlet. Worse, reducing the flush volume often means the toilet does not clear properly, leading to multiple flushes that use more water than a single proper flush.
If you want to save water on toilet flushing, the real solution is a modern dual-flush system. A 3-litre half flush and 4.5-litre full flush uses far less water than an old single-flush toilet, and the system is designed to work properly at those volumes.
Myth 6: All Plumbers Are the Same
The Myth
Any licensed plumber can handle any job equally well, so just go with the cheapest quote.
The Reality
Plumbing is a broad trade with many specialisations. A plumber who excels at residential bathroom renovations may have limited experience with commercial plumbing systems. Gas fitting requires a separate licence and specific training. Drain clearing and pipe relining need specialised equipment that not every plumber carries.
Always check that your plumber has relevant experience for your specific job, and verify their licence covers the type of work required.
Myth 7: All Leaks Are Obvious
The Myth
If you had a water leak, you would know about it.
The Reality
Many of the most damaging leaks are completely invisible. Pipes running behind walls, under concrete slabs, and through ceilings can leak for months or even years before any visible signs appear. By the time you notice a damp patch on a wall or ceiling, significant damage may have already occurred to your home's structure.
Watch for subtle signs: an unexplained increase in your water bill, the sound of running water when no taps are open, musty smells, or small patches of mould. Professional leak detection services use acoustic sensors, thermal imaging, and moisture meters to locate hidden leaks without tearing open walls.
Myth 8: You Do Not Need a Licensed Plumber for Minor Repairs
The Myth
Small plumbing jobs like replacing a tap or fixing a leaking toilet do not require a licensed plumber.
The Reality
Under NSW law, almost all plumbing work must be performed by a licensed plumber. This includes any work on water supply pipes, drainage systems, gas lines, and fixtures connected to these systems. The only exceptions are very minor tasks like replacing a shower head or tightening a leaking tap handle.
There is a good reason for this rule. Improperly installed plumbing can contaminate drinking water, cause flooding, or create gas hazards. If unlicensed work causes damage, your home insurance may refuse to cover the claim. The small amount you save by doing it yourself is not worth the risk.
Myth 9: Hot Water Systems Last Forever
The Myth
Once a hot water system is installed, it will run reliably for decades without attention.
The Reality
Every hot water system has a finite lifespan. Electric storage tanks typically last 8 to 12 years, gas storage systems 10 to 15 years, and heat pumps around 10 to 15 years. Continuous flow units can last 20 years or more with proper maintenance, but they are not immune to failure.
Regular servicing -- including checking the sacrificial anode in storage tanks, testing the pressure relief valve, and flushing sediment -- can extend your system's life significantly. Waiting until it fails completely often means an emergency replacement at a premium price, plus the inconvenience of being without hot water.
Myth 10: All Plumbing Emergencies Can Wait Until Morning
The Myth
If a plumbing problem happens at night, you can just turn off the water and deal with it in the morning.
The Reality
Some plumbing emergencies genuinely cannot wait. A burst pipe flooding your home causes more damage with every minute that passes -- saturating floors, walls, and electrical systems. A gas leak poses an immediate safety hazard to everyone in the property. Sewage backing up into your home creates a serious health risk.
Whilst a slowly dripping tap can certainly wait until business hours, knowing the difference between an inconvenience and a genuine emergency can save you thousands in damage. When in doubt, call a plumber who offers 24/7 emergency service.
The Bottom Line
Plumbing myths persist because they sound plausible, but acting on bad advice often turns a small problem into an expensive one. When you are unsure about a plumbing issue, the safest approach is always to consult a licensed professional. A quick phone call for advice costs nothing and could save you a great deal.
Have a plumbing question or need expert advice? Call us on 0404 939 121. We are always happy to help Sydney homeowners separate fact from fiction.
Written by
Licensed plumbing specialists (Lic. 369675C) with 10+ years of experience serving Sydney homes and businesses. Available 24/7 for emergency plumbing, blocked drains, hot water, gas fitting, and more.
