Half past six on a Tuesday in Prestons, and you're standing in a shower that's filling faster than it's draining, grey water lapping at your ankles, twenty minutes before you need to be out the door. I've had that phone call more times than I can count, and my answer is usually the same: don't ring me yet. A blocked shower drain is one of the few plumbing problems most people can fix themselves in the time it takes the kettle to boil, and I'd rather you spent the call-out fee on something that actually needs me.
Here's the quick version. Nine times out of ten the blockage is hair and soap scum packed into the first 300 mm of pipe, right under the grate. Pull the grate, hook it out, flush with hot water, done. What you should not do is pour a tin of caustic drain unblocker down there. And if the shower is slow at the same time as the toilet is gurgling or the gully outside is overflowing, stop, because that's not a shower problem, it's a sewer problem. If you would rather hand it to a licensed blocked drains plumber, no call-out fee, ring 0455 222 292 and Paul answers.
Most blocked shower drains are hair and soap scum sitting just below the grate. Pull the grate, hook the hair out with a cheap plastic drain snake, flush with hot tap water, and you're done in ten minutes. Skip the caustic soda: it heats up in the pipe, damages old pipework and makes the job dangerous for whoever opens the trap next. If every drain in the house is slow, or the gully outside is overflowing, the problem is the main line and that's a plumber job.
Why shower drains block
Hair is the frame and soap is the mortar. Long hair wraps around the grate fixings and the trap, then soap scum, conditioner, skin and body fats build up on it until you've got a solid plug that water has to seep through. A slow draining shower is the early warning, usually weeks before it stops altogether. In older brick homes around Cabramatta the floor waste and trap can be old galvanised steel or cast iron, rough on the inside and narrower than it was new, so it grabs hair faster. In the new estates at Edmondson Park I pull out something different: tile grout, render and silicone offcuts washed down during the build that set like concrete in the trap. Different cause, same puddle.
How to unclog a shower drain yourself
You'll need a torch, gloves, a bucket and, ideally, a plastic drain snake. That's the flat barbed strip you can buy at any hardware store for a few dollars, and it's the most useful drain tool you can own.
- Lift the grate. Most are push-fit or held by one or two screws.
- Shine the torch down and pull out anything you can reach by hand.
- Feed the drain snake in as far as it goes, twist it a couple of turns and pull it back slowly. Repeat until it comes up clean. Bin the hair; don't flush it down the toilet.
- Run the shower on hot for a minute to flush the loosened soap through. Hot tap water is enough. Don't tip a kettle of boiling water into plastic pipework, and never into a drain you've just put chemicals in.
- Still slow? Put a plunger over the waste so it covers the opening completely and give it a dozen firm pumps. If there's a bath on the same trap, block its outlet with a wet rag so you're pushing on the blockage and not just moving air.
Bicarb soda and vinegar gets a lot of airtime online. It fizzes, which is satisfying, and it won't hurt anything, but it doesn't shift a plug of hair. A wet and dry vac set to suck, sealed over the drain with a rag, does more. If ten minutes with the snake and plunger hasn't cleared it, the blockage is further down than you can reach and it's time to stop.
What not to pour down a blocked shower drain
Caustic soda and the chemical drain unblockers built on it (sodium hydroxide, mostly) work by reacting with water and organic matter, and that reaction makes heat. In a clear pipe the heat passes through. In a blocked pipe the chemical sits on top of the plug and keeps reacting in one spot. That heat softens PVC, and on older galvanised or cast iron it attacks metal that's already thin and corroded, so a blocked drain becomes a leaking drain. I've replaced traps in Cabramatta that were fine until a couple of bottles of drain unblocker went through them. The other problem is me. When the chemical doesn't work, someone rings a plumber, and the first thing I do is open the trap or put a plunger on it. A trap full of undissolved caustic soda splashing back at face height is a genuine chemical burn risk, which is why I always ask what's been poured down before I touch anything. Tell your plumber the truth on that one.
Bleach doesn't dissolve hair either, and mixing bleach with an acid or ammonia based product in a closed pipe makes fumes you don't want in a small bathroom. If a product promises to dissolve a blockage, it's promising to dissolve your pipes too, just more slowly.
Blocked kitchen sink or bathroom basin? Same idea, different muck
The method above works on any bathroom drain blocked with hair, but the kitchen is a different animal. A blocked kitchen sink is nearly always fat and food scraps, which set hard in the trap under the sink as they cool. Put a bucket under the trap, unscrew it by hand, tip it out, rinse and refit. Plunge with the overflow covered if the pipe past the trap is the problem. And stop pouring cooking fat down the sink, because it's the reason I see the same kitchen sinks again six months later. Bathroom basins clog with hair and toothpaste at the pop-up waste: lift the plug out and clean the stem. If the pop-up mechanism itself has failed, that's a taps and fixtures job rather than a drain job.
| Drain | Symptom | Usual cause | DIY or plumber? |
|---|---|---|---|
| Shower | Slow, water pools at your feet | Hair and soap scum in the trap | DIY: snake and plunger |
| Kitchen sink | Slow, greasy smell | Fat and food in the trap | DIY: clean the trap |
| Basin | Slow, pop-up plug sticks | Hair and toothpaste on the plug stem | DIY: pull the plug and clean it |
| Shower plus a gurgling toilet | Toilet bubbles when the shower drains | Blockage in the main line | Plumber: jet blaster and camera |
| Every drain in the house | All slow, sewer smell, gully overflowing outside | Sewer blockage, often tree roots | Plumber, today |
Signs it's not the shower at all
A shower drain blocked with hair affects one fixture. If more than one drain is slow, if the toilet burps when the shower runs, if the bath fills when the washing machine empties, or if you can smell sewer in the bathroom, the blockage is in the pipe all of those share. Go outside and find the overflow relief gully, the grated drain near an outside wall that sits lower than any fixture inside so that a blocked sewer overflows there instead of into your shower. If it's wet, bubbling or has water sitting in it, the main line is blocked and the gully is doing its job. That's tree roots or a collapsed section more often than not, and it needs the jet blaster and the CCTV camera, not a plunger. The blocked drain guide goes into what the camera finds and what it costs to fix, and there's a separate post on sewer smells in the house.
What it costs if you do need a plumber
Sydney 2026 price guides put a blocked drain clear at $180 to $450, with call-out fees of $69 to $170 on top. A CCTV drain inspection is quoted on inspection and often bundled with the clear. What moves the price is access, whether the jet blaster is needed, and the hour of the day. Be honest about urgency: a slow shower that still drains can wait until Monday morning, and with us the rate is the same whenever you book. Sewage coming up through the shower waste, or an overflow relief gully spilling across the yard, can't wait, and that's what the 24/7 emergency line is for.
When to call a plumber
Ring me when the snake and plunger have failed, when the same shower blocks every few weeks no matter how much hair you pull out, when more than one fixture is slow, or when there's water in the gully outside. Ring straight away if anything is coming up that should be going down. A repeat blockage in one shower usually means a damaged or badly laid trap, and that's licensed work: in NSW, plumbing and drainage has to be done by a licensed plumber, and a shower waste sits under the waterproofing, which is no place for guesswork. Done right. Done once.
Monarch Civil & Plumbing clears drains across South West Sydney and the Macarthur region. See our blocked drains service page, find your plumber in Prestons or plumber in Cabramatta, and ring 0455 222 292 when the plunger isn't enough. You'll get a price before the work starts.
Related guides: jet blasting blocked drains and blocked drain causes and fixes.
Need it sorted? Ring 0455 222 292 any hour or book online. Monarch Civil & Plumbing is a blocked drains plumber, no call-out fee, across Liverpool, Fairfield, Campbelltown and Camden, and the rate is the same after hours.
Blocked drain in Liverpool, Fairfield or Campbelltown?
The local pages say what is usually wrong in your suburb and what Paul does about it: blocked drains Liverpool, blocked drains Fairfield and blocked drains Campbelltown. Everywhere else within about 20 km of Austral, the blocked drains page covers how a job runs and service areas lists every suburb. No call-out fee anywhere, and the camera goes down before anything is quoted.
Frequently asked
What dissolves hair in a shower drain?
Nothing you can buy dissolves hair without also attacking the pipe, which is why plumbers pull it out instead. A plastic drain snake, the barbed strip sold at hardware stores for a few dollars, hooks the whole plug out in a couple of passes. Follow it with a minute of hot tap water. Bicarb soda and vinegar is harmless but does very little, and caustic products create heat that damages old pipework.
Is caustic soda safe to use on a blocked shower drain?
I would not use it. Caustic soda reacts with water and makes heat, and in a blocked pipe that heat sits in one spot, softening PVC and eating into old galvanised or cast iron traps. If it fails to clear the blockage, the chemical stays in the trap and becomes a burn hazard for whoever opens it next. If you have already used it, tell your plumber before they touch anything.
Why does my shower drain keep blocking?
If you are pulling hair out every few weeks, something is catching it. A rough or corroded old trap, a badly laid waste with the wrong fall, or a partial blockage further down the line will all grab hair that would otherwise wash through. A partial main line blockage from tree roots shows up first as a slow shower, since it is usually the lowest fixture. A camera inspection finds which one it is.
Can I use a drain snake on a shower drain?
Yes, and it is the first thing I would reach for. A cheap plastic barbed strip is ideal because it cannot damage the trap or the waterproofing. Feed it in gently, twist, and pull back slowly. A metal auger will go further but can scratch chrome fittings, gouge old pipes and get stuck in a trap bend, so on a shower waste it is a job for someone who has done it before.
Why is my shower draining slowly but not fully blocked?
A slow draining shower is a partial blockage, and it is the best time to act. Hair and soap have narrowed the trap but water still seeps through. Clear it now with the snake and it takes ten minutes. Leave it and the plug hardens until nothing moves. If other drains are slow too, or the toilet gurgles when the shower runs, the restriction is in the main line, not the shower.
How much does it cost to unblock a shower drain in Sydney?
If you can clear it yourself with a drain snake, a few dollars. If a plumber is needed, Sydney 2026 price guides put a blocked drain clear at $180 to $450, with call-out fees of $69 to $170 on top depending on the time of day. A camera inspection is quoted on inspection and often bundled with the clear. A slow shower that still drains can wait for business hours and skip the night call-out.
Licensed plumber and drainer based in Austral, 13+ years in the trade, working across Liverpool, Fairfield and the Macarthur region. About Paul