How to Fix a Leaking Tap: Washers, Ceramic Discs and Mixers, and When to Call
A dripping tap is one of three things: a worn washer on a traditional tap, a worn cartridge in a ceramic disc tap, or a worn cartridge or O-ring in a mixer. The washer is a twenty-minute job with the water off. The other two are cartridge swaps that depend on the brand. Here is how to tell which tap you have, the step-by-step for each, why a new washer sometimes still drips, and when the fix is a plumber.
Turn off the isolation valve under the basin or the water at the meter, open the tap to release pressure, and plug the drain before you undo anything. A new washer that still drips means the seat is worn and needs reseating or the tap needs replacing. Mr Splash quotes tap repairs as one fixed price, GST included, before any work starts.
Which Tap Do You Have?
The fix depends entirely on what is inside the tap, and the handle tells you.
Traditional Washer Tap
The handle turns two or three full turns to open. Inside is a spindle that screws down onto a rubber washer (a jumper valve) sitting on a brass seat. Drips from the spout mean the washer; leaks from around the handle mean the O-rings or body washer.
Ceramic Disc Quarter-Turn Tap
The handle turns a quarter turn from off to full on. Inside is a cartridge with two ceramic discs. Drips mean the cartridge is worn or has grit between the discs; it is replaced as a unit, matched to the brand.
Mixer Tap
One lever for hot and cold. A single cartridge inside controls both. Drips from the spout, or a lever that has gone stiff or loose, mean the cartridge; leaks from the base of the spout mean the O-rings around the body.
Before You Start: Turn the Water Off Properly
- Find the isolation valve. Under a basin or sink there is usually a small tap on each supply hose; turn it clockwise until it stops. Bathroom wall taps and older kitchens often have none, in which case turn the water off at the meter tap at the front boundary.
- Open the tap you are fixing until the flow stops completely. That releases the pressure and confirms the water is actually off. If water keeps coming, the isolation valve is not holding and the meter is the answer.
- Put the plug in. Small screws and washers go down the plughole with depressing regularity.
- Lay a towel in the basin and put the parts down in the order they come off. A photo at each stage costs nothing.
How to Fix a Leaking Washer Tap, Step by Step
- Remove the handle. Prise off the cap on top, undo the screw beneath it, lift the handle off. Then unscrew the decorative flange or skirt by hand or with a cloth-wrapped wrench.
- Unscrew the spindle with a spanner or shifter, anticlockwise. It lifts out with the washer sitting on its end or left behind on the seat.
- Replace the washer. Take the old one to the hardware store to match the size, or buy a mixed pack. Fit the new one on the jumper valve, and while it is apart replace the O-rings on the spindle and the body washer under the spindle head; they are the cause of leaks around the handle.
- Look at the seat. Shine a torch down the tap body at the brass ring the washer closes onto. If it is pitted, scored or has a ridge, a new washer will drip within weeks. A reseating tool grinds it flat and is sold at hardware stores; if the seat is badly worn the tap body is replaced.
- Reassemble in reverse, spindle firm but not overtightened, handle back on, then turn the water on slowly and check for drips at the spout and around the handle.
Ceramic Disc and Mixer Taps: The Cartridge Swap
A quarter-turn tap comes apart the same way as a washer tap, but instead of a spindle and washer there is a cartridge that lifts out whole once its retaining nut is undone. It is replaced, not repaired: grit between the ceramic discs scores them and no cleaning restores the seal. The catch is the part. Cartridges differ by brand and by model year, so take the old one with you or note the tap brand from the handle or the base.
A mixer has a single cartridge under the lever. Undo the small grub screw on the lever, lift the lever off, unscrew the dome cap, undo the retaining nut and lift the cartridge out. The new one must be the same brand and size, and it has to seat with its alignment tabs in the right place or the hot and cold will be reversed. Leaks from the base of the spout on a swivel mixer are the O-rings around the body, reached by lifting the spout off.
For most people this is where the plumber earns the call: the cartridge is the whole job, and a plumber carries the common brands and can identify an unbranded tap from the fitting. A replacement tap is often the better answer on a cheap mixer where the cartridge costs nearly as much as a new tap.
Why a Tap Still Drips After a New Washer
Worn Seat
The brass seat the washer closes onto is pitted or ridged. A reseating tool grinds it flat; a badly worn seat means a new tap body. The most common reason a DIY washer swap fails.
Wrong Washer
A washer that is too small or too hard does not seal. Match the diameter exactly, and use the correct hot or cold type where the pack separates them.
Damaged Spindle
A spindle with worn threads does not hold the washer square on the seat. Spindles are replaceable on most taps.
High Water Pressure
Sydney mains pressure above what the tap is rated for wears washers and cartridges fast and causes hammer. A pressure limiting valve at the meter protects every tap in the house.
Grit in a Ceramic Cartridge
Sand or scale between the discs scores them and the tap drips again within days. Flushing the line before fitting the new cartridge helps; a filter at the meter helps more.
The Tap Is Just Old
Corroded bodies, seized spindles and cracked flanges are not worth chasing. A new tap set is quoted as a fixed price and comes with a warranty.
When to Call a Plumber
Swapping a washer on your own tap is a job most homeowners do. Replacing taps, mixers or the flexible hoses under a basin, reseating a worn seat, fixing a leak at the wall or under the sink, and any work on the pipework or the isolation valves is licensed plumbing work in NSW, and it is where the risk sits: a cross-threaded fitting or a hose left under strain can flood a bathroom overnight.
Call when the isolation valve will not turn or will not hold, when the spindle is seized, when a new washer still drips, when a mixer cartridge cannot be identified, when the leak is under the sink or at the wall rather than the spout, or when the tap is old enough that replacing it is the sensible answer. A leaking tap wastes water every hour and a leak under a sink rots the cupboard, so neither is worth living with.
Mr Splash repairs and replaces taps across Sydney as one fixed price, GST included, confirmed before any work starts, with no charge just to come and look during business hours. The leaking tap repairs page has the booking form, and the plumber prices guide lists current Sydney market ranges for tap repairs with their sources.
Leaking Tap Questions, Answered
How do I fix a dripping tap?
Turn the water off at the isolation valve or the meter, open the tap to release pressure and plug the drain. On a traditional tap, remove the handle and flange, unscrew the spindle, replace the washer and O-rings, check the seat, and reassemble. On a quarter-turn or mixer tap, the cartridge is replaced as a unit, matched to the brand.
Why does my tap still drip after replacing the washer?
Usually the brass seat the washer closes onto is pitted or ridged, so the new washer cannot seal. A reseating tool grinds it flat; a badly worn seat means replacing the tap. A wrong-sized washer, a worn spindle or very high water pressure are the other causes.
How do I know if my tap has a washer or a ceramic disc?
A handle that turns two or three full turns to open has a washer. A handle that turns a quarter turn from off to full on has a ceramic disc cartridge. A single lever that controls hot and cold is a mixer with its own cartridge.
Can I change a tap washer myself in NSW?
Swapping a washer on your own tap is commonly done by homeowners. Replacing the tap or mixer, the flexible hoses, the isolation valves, or any work on the pipework is licensed plumbing work in NSW.
How much does it cost to fix a leaking tap?
Sydney market trackers put a leaking tap repair at $92 to $300 per job and a tap replacement at $92 to $400 per tap (whatsthedamage.com.au, prices verified September 2026). Those are market figures, not Mr Splash prices. Mr Splash quotes tap work as one fixed price, GST included, before starting.
Why is my mixer tap leaking from the base?
The O-rings around the body of a swivel mixer have worn, so water escapes where the spout turns. The spout lifts off once its retaining ring is undone and the O-rings are replaced; if the body is scored, the mixer is replaced.
Is a leaking tap an emergency?
A drip from the spout is not. A leak under the sink, at the wall, or from a flexible hose is: turn the isolation valve or the meter off and call, because a burst hose can flood a room in an hour.
Related: Leaking tap repairs · Tap repairs · Burst flexi hose · Plumber prices Sydney
