How to Fix the 13 Most Common Causes of Blocked Drains

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How to Fix the 13 Most Common Causes of Blocked Drains


You can experience blocked drains at any time of the year, and no matter when they pop up, they are always a headache. Here’s an essential list of all the common causes of blocked drains in the home and what you can do to fix them and prevent them in the future with some good maintenance habits.


What are the common causes of blocked drains?

1. Cat litter

Cat litter is usually composed of silica, clay, and sand, designed to absorb moisture and create clumps. As such, it is terrible for drainage systems because the clumps can easily block your pipes. Always dispose of your kitty litter by bagging it and disposing of it in the trash instead of flushing it down any drain. Avoid using commercial drain cleaner as these can corrode your pipes over time. Instead, we recommend using a combination of a toilet snake and a plunger. 


2. Dirt

Don’t be fooled into thinking that you can wash away as much dirt as you want down the drain. Dirt can build up and cause clogs, especially when combined with soap residue, grease, or hair. Using a plunger or a plumber’s snake are common approaches that effectively get the drain unblocking job done. You can prevent dirt blockages by shaking off excessive dirt or rinsing yourself before you head indoors.


3. Feminine products and cotton swabs

Feminine products such as sanitary napkins or tampons should never be flushed down the toilet as they can block drains. Because they’re made of cotton, they can expand to up to 10 times their original size once they’ve absorbed liquid, and unlike toilet paper, they don’t break down or dissolve. Plunging or the use of a plumber’s snake can work, but if it does not, it’s time to call a plumber. 


4. Food waste

Food waste blockages are a common problem for kitchen sinks. Even with garbage disposal, it’s still possible for food waste to clog up pipes. Tea leaves and coffee grounds are especially bad since they don’t decompose quickly enough and swell after absorbing water which blocks your drains. Plungers, drain cleaners, or plumber’s snakes can solve this problem. If your sink is equipped with garbage disposal, you might have to detach it for inspection, cleaning, or even replacement. It’s best practice to have a segregated compost bin for food waste instead of putting food waste down drains, even if you do have garbage disposal.


5. Hair

Human and animal hair are common contributors to blocked pipes in shower, laundry and bathroom drain. Things get even worse when human and animal hair combine with other substances like soap residue and grease. Use a plunger or a plumber’s snake when this happens. If it needs extra help, a homemade drain cleaner made of vinegar and baking soda will help dislodge that stubborn block. To avoid blocked drains in the future, use a hair strainer guard to prevent hair all from flushing down the drain and clean it regularly.


6. Mineral build-up

Hard water that is rich in mineral deposits like calcium and magnesium can cause blocked drains over time by creating a filmy scale. Mineral deposits can cause backup and reduce flow with enough build-up. You will need the help of a professional plumber to descale your pipes if this happens. To avoid this in the future, install a water softener to prevent future build-ups.


7. Objects accidentally flushed

Various items can find themselves flushed down the toilet accidentally, whether the usual or unusual things that clog up your pipes. Children can accidentally flush their small toys into the bowl or clog bath or sink drains unprotected by a guard if they play with them during bath time. Using a plunger or a plumber’s snake should be tried, but you may require a professional plumber if the object is too stubbornly lodged. Avoid having objects unexpectedly blocking your drains by using drain guards and educating kids to not use the toilet fixture as a plaything.


8. Offset pipes

The ground can shift and settle over time, causing the older style pipes made of three-foot sections of concrete and clay to move out of place. Shifting pipes can affect the water flow from the home to the public sewer system, depending on gravity. You will need professionals to sort this out as it may involve significant excavation work. Professional diagnosis will probably require CCTV drain cameras to explore the state of the pipes as it may be challenging to assess whatever is going on underground without cameras properly.


9. Oil, fat, and grease

Never underestimate the damage accumulated grease, oil, and fat can do to your drain system. The problem is that oil and grease can solidify in the pipes and block your drains. Grease, oil, and fat can do to your drain system. Try mixing some hot water and detergent or dish soap and pour it down the drain. This will soften or break down the solidified oil and then try plunging or using the plumber’s snake again. As a preventive measure, wipe up small amounts of oil with a paper towel and dispose of it via compost rather than trying to rinse it down the drain. 


10. Plants and leaves

External drains are particularly susceptible to getting clogged up by plants and dried leaves, especially during the Autumn season. It’s possible to remove the block by simply fishing out any plants and leaves, but if the problem goes deeper, it may be time to contact a plumber to unblock the drains. You can avoid blocked external drains by covering them with drain grills and keeping your yard clear of fallen leaves and plants.


11. Soap

Soap residue accumulates over time in laundry, bath and shower drains, especially when combined with accumulated hair. Soap scum reduces the diameter of the drain pipe and causes gradual slow drainage and backups. Pressure cleaning is an ideal way to eliminate soap buildup in your pipes and you can avoid future buildup by using soap-free washes.


12. Too much toilet paper

If you’re a bit over-eager in using toilet paper, this may cause some issues when trying to flush your toilet, but when used in moderate amounts, won’t give you any problems. Using a plunger or a plumber’s snake will usually fix things up. Use toilet paper in moderation; if necessary, don’t try flushing all the toilet paper down in one go. Try disposing of small batches over several flushes instead.


13. Tree roots

Tree roots can make their way inside pipes through even the smallest cracks. There are certain species of trees which are notorious for their ability to choke and destroy sewerage and stormwater drains. Once they penetrate the pipe, the roots will grow, obstruct more water flow over time, and cause damage. You will need to call professionals to resolve this problem as excavation might be necessary. Make it a point to know the root structure of your plants and trees and schedule a periodic assessment of your drains by a professional, especially as pipes deteriorate over time.


At some point over the lifespan of your property, these common causes of blocked drains are bound to happen. With awareness and good common sense with these tips in mind, you will prevent them from occurring and have the confidence to tackle them immediately if and when you need to unblock your drains. If all else fails, call us at 1300 403 201

One of the Director of Sydney Blocked Drains.

Patrick Noone

Director of Sydney Blocked Drains

Patrick Noone is a highly skilled and experienced professional in the plumbing industry, with a particular focus on blocked drains. As the director of Sydney Blocked Drains, he brings a wealth of knowledge and expertise to every job he undertakes.

Our Speciality Is
Blocked Drains In Sydney

We conduct CCTV drain inspections to unblock drains, no dig pipe relining and repairs to locals. We’re your 24 hour emergency plumber for that!
Our highly skilled team of drain experts have been specifically trained in diagnosing & repairing blocked and broken drains.
Our vehicles are fully equipped with all the cutting edge drain clearing & locating technology. This enables us to not only find the blockage quicker, but also provide long term solutions to eliminate the problem for good.
Regular plumbers often do not have the knowledge or equipment to handle complex blocked drain jobs, and may cause extensive damage and mess to your property, without fixing the problem.
Blocked drains in Sydney need to be handled by an expert, so don’t waste your time or money on inferior plumbers who aren’t qualified to get the job done properly.

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