GerardPreventing blocked drains comes down to minimising what enters your pipes, cleaning strainers and grates regularly, and acting early the moment drainage starts to slow. Most blockages build up gradually from fat, hair, food scraps and debris rather than happening overnight. Below, we’ve broken down exactly what causes blockages, room by room prevention tips, a simple maintenance schedule, and what to do if the problem keeps coming back.
Quick blocked-drain prevention checklist
Use strainers
In kitchen sinks, showers and baths
Keep oil and grease out
Cooking oil, grease and food scraps out of sinks
Flush only the essentials
Human waste and toilet paper only
Clear hair regularly
Remove hair from drain covers often
Protect outdoor drains
Keep leaves, soil and sand away
Don’t ignore warning signs
Slow drainage, smells or gurgling
What causes blocked drains?
Blocked drains are often caused by foreign objects entering the system and usually develop over time. They restrict pipes, causing blockages and damage to drainage systems.
Fat, oil and grease
These often get poured down the drain because it’s convenient, but they cool and stick to the inside of pipes, eventually restricting water flow.
Food scraps and coffee grounds
Similar to oils, these get rinsed down sinks and collect in pipes. They can then combine with fat and grease to create a mega block.
Hair and soap residue
Hair can catch inside bathroom drains and bind with soap to create blockages.
Wet wipes and sanitary products
Even products labelled “flushable” may not break down as easily as toilet paper.
Excess toilet paper
Flushing too much at once can create a blockage, particularly in older or restricted pipes.
Foreign objects
Cotton buds, dental floss, toys, nappies and paper towels can become lodged in pipes.
Leaves, soil and sand
Outdoor and stormwater drains can become blocked when garden debris washes through the grate.
Tree roots
Roots can grow through small cracks or loose pipe joints and continue growing inside the drain.
Damaged or collapsed pipes
Cracks, corrosion, movement and collapsed sections can restrict water flow and trap debris.
Incorrect drainage falls
Poorly installed pipes may lack sufficient slope to carry water and waste away effectively.
How to prevent blocked kitchen drains
Scrape plates before washing
Scrape leftover food off plates and cookware into the bin before washing up.
Use a sink strainer
Fit a drain strainer to your sink, and empty and rinse it regularly.
Don’t pour fats and oils down the drain
Let them cool, then dispose of them in a sealed container instead.
Keep dry goods out of the sink
Coffee grounds, flour, rice, pasta and food scraps should go in the bin. Let the strainer do its job.
Act early on warning signs
Address recurring smells or slow drainage before the pipe becomes fully blocked.
How to prevent blocked shower, bath and bathroom drains
Install a hair catcher
Fit a removable hair catcher for your sink, shower and bathroom drains.
Clean the grates regularly
Remove collected hair and clean the grates on a regular basis.
Brush long hair before showering
This reduces loose strands getting stuck in drains.
Keep small objects away from drains
Dental floss, cotton buds and other small items should never go near the drain.
Investigate pooling water early
Look into water pooling around the drain rather than letting it worsen.
How to prevent blocked toilets
Only flush the essentials
Toilet paper and human waste only, nothing else should go down.
Bin your wipes
This includes products marketed as flushable. “Flushable” doesn’t always mean it flushes.
Never flush sanitary products
Sanitary products, nappies, paper towels and cotton products should go in a small bin beside the toilet instead.
Teach kids the rules
Help children understand what can and cannot be flushed.
How to prevent blocked laundry drains
Check filters and pockets first
Check the washing machine’s lint filters and pockets before washing.
Inspect the discharge hose
Look for kinks, movement or damage in the hose.
Don’t ignore backups or overflow
Water backing up or overflowing in the laundry is a sign something needs attention.
Watch for wider drainage issues
Laundry drainage trouble can sometimes point to a larger household blockage.
How to prevent blocked outdoor and stormwater drains
Clear grates and gutters
Remove leaves and debris, especially before heavy rain.
Keep garden waste out of drains
Try to prevent soil, mulch, sand and garden waste from washing in.
Plan landscaping carefully
Avoid planting aggressive trees with roots close to known underground drainage routes.
Investigate recurring issues
Look into pooling water, overflowing grates and recurring outdoor blockages.
Simple drain-maintenance schedule
Should chemical drain cleaners be used preventively?
Chemical drain cleaners definitely have their time and place, but shouldn’t be treated as routine maintenance. They won’t address tree roots, damaged pipes or solid objects stuck in the pipe, and repeated or incorrect use can create safety and pipework concerns.
Early warning signs of a blocked drain
Slow drainage
Water is draining more slowly than usual.
Gurgling sounds
From sinks, toilets or showers.
Unpleasant smells
A persistent drain odour that doesn’t clear.
Water rising elsewhere
Water rising or bubbling in another fixture, or changing toilet-water levels.
Outdoor overflow
Grates overflowing or the surrounding ground staying wet.
Repeat blockages
The same blockage returning after DIY treatment.
When preventative measures are not enough
If blockages keep coming back no matter how closely you’ve followed preventative measures, the cause is usually something you can’t fix from above ground. Tree roots can work their way into small cracks or loose joints and keep growing inside the pipe. Pipes can also crack, corrode or collapse over time, especially in older homes, restricting flow and catching debris. Sometimes the issue comes down to incorrect drainage falls, where the pipe simply wasn’t laid with enough slope to carry water away properly. Heavy grease build-up over months or years can also narrow a pipe until it’s barely functioning, and in some cases the real blockage isn’t in your home’s plumbing at all, but further down in the main sewer line.
This is where a proper inspection makes all the difference. At GXR Plumbing and Gas, we use CCTV drain inspections to see exactly what’s happening inside the pipe before recommending a fix, paired with professional drain-cleaning equipment to clear blockages without damaging the pipe. Where there’s structural damage, we offer both pipe repairs and relining, so you’re not always stuck with a full dig-up.
Same blockage keeps returning?
Book a CCTV drain inspection with GXR on 08 6374 9998
Frequently asked questions
How do I prevent blocked drains?
Control what goes into your pipes, clean strainers and grates regularly, and act as soon as drainage starts to slow rather than waiting for a full blockage.
Do coffee grounds block drains?
Yes. Coffee grounds don’t dissolve and can build up in pipes over time, especially when combined with fat and grease.
Can hair block drains?
Yes. Hair is one of the most common causes of bathroom drain blockages, particularly when it binds with soap residue.
Can soap block drains?
Soap scum can combine with hair and other debris to form a solid mass inside pipes over time.
Can heavy rain cause blocked drains?
Yes. Heavy rain can wash leaves, soil and debris into outdoor and stormwater drains, causing sudden blockages.
Can a blocked drain cause a leak?
Yes. Pressure from a blockage can force water to find another way out, potentially leading to leaks in the pipe.
Can blocked drains cause flooding?
In severe cases, yes, particularly with blocked stormwater drains during heavy rain.
Can a blocked drain cause unpleasant smells?
Yes. Trapped food, grease and organic matter can decompose in the pipe, producing a persistent odour.
