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Reasons Why Your Toilet Keeps Blocking

Of all the plumbing mishaps to occur around the home, a blocked toilet has to be one of the absolute worst for a homeowner to handle, especially when it takes you by surprise. It’s tough to clean up afterwards, becomes a nightmare when you have company and depending on the cause, can be a tough fix.

Looking to diagnose what’s going wrong when you find your toilet and sink blocked? Here are a few things to consider:

A Low-Flow Toilet

Since the 1990s, low-flow toilets have been widespread as a way to clear waste while also using less water. The result is an environmentally friendly flush that also saves money on your water bill.

However, while the technology has come a long way, low-flow toilets aren’t all made equal, with some of the cheaper models not able to produce enough force to clear the pipes. If you find your toilet clogging repeatedly, this might just be the problem.

Low Water Pressure

This problem can affect your entire home, with blocked pipes either causing low water pressure or low water pressure being the reason your pipes aren’t able to clear. The causes range from buildup of rust inside older pipes to an invasion of tree roots and soil, but regardless of how it happens, your lack of water pressure can easily affect your toilet’s ability to flush solid waste.

If your toilet keeps getting clogged, then you can also check to see if the pressure around the rest of your home is weak; this might just end up being the problem.

Blocked Toilet Trap


The toilet trap is the curving channel that connects the bottom of the bowl to the drainage pipe. It most commonly gets clogged by people flushing items that simply shouldn’t be flushed, such as hygiene products and more solid items (such as when children drop toys into the bowl for fun). Found that your toilet keeps blocking? It might just be a buildup inside the trap.

Because the blockage exists inside the ‘curve’, it often requires specialised equipment to properly remove. Out of all the blocked toilet causes, this is perhaps the simplest to prevent, but not as easy to remove by yourself.

Blocked plumbing vent 

The plumbing vent is a system that allows air to flow through your plumbing system, carrying away odours and bad smells. If this pipe becomes blocked, it can lead to low water pressure in your home, as well as a blocked toilet that isn’t able to properly flush.

The pipe often winds through the walls and vents on the roof of a home, making it a much greater challenge for an untrained individual to fix. Unclogging a plumbing vent can require breaking down walls, working on the roof and the use of specialised equipment, making it a problem best handled by professionals.

Main Sewer Clog

Pipe clogYou may not give much thought to the sewers under your home, but if they become blocked, it can have disastrous consequences. Blocked sewers can cause similar blockages all around your home while regurgitating dirty water, which can cause permanent damage and make toilets and sinks unusable until the problem is fixed.

Gurgling, random leaks and water coming back up from toilets and sinks are the most common signs of a sewer clog, and the problem will often grow worse with time if not treated by a professional.


Preventative Measures

While some blockages are simply caused by older pipes or tree root invasions, there are a few things you can do to prevent similar problems in the future:

  • Pipe clogThe only thing that’s meant to be flushed is waste and toilet paper, the latter of which is specially made to break down in the pipes. Hygiene products, tissues, paper towels and wet wipes (even the ones marked ‘flushable’) don’t belong in the toilet.
  • A basic clean of your toilet on the regular should help keep the water flowing, even when using simple products such as vinegar.
  • Keep a close eye on your toilet’s inner workings. Check the parts every few months and don’t simply ignore any strange sounds.

 The Drainage Experts

While you can sometimes remove a blockage with a plunger and some determination, a lot of blocked toilet problems run deeper. Drain replacement and sewer repair are huge tasks that require specialised tools, experience, expertise and in serious cases, digging equipment.

Our Melbourne Drainpro technicians have extensive experience in dealing with all kinds of problems: for simple toilet unblocking, we use drain camera inspection tools to ascertain the source of the problem and deal with it quickly and efficiently.


For larger issues, such as blocked plumbing vents and sewer clogs, we use high-pressure jet cleaning equipment that’s proven to clear almost all types of blockage in short order, without causing any lasting damage. In extreme cases, we’re also able to expertly take apart inner wall plumbing systems and undertake ground excavation, performing repairs and replacement and leaving your pipes working as good as new.

From a simple blockage to full-blown sewer repair, Drainpro no toilet unblocking job is too big or small for Drainpro. If your toilet keeps blocking, or you have any of the problems mentioned above, give our friendly team a call today on 1300 620 273, or send us a message using our contact form.

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