Bathroom · DIY guide
How to replace a tap washer
A dripping tap wastes around 20,000 litres a year and is usually a $3 washer. In Victoria you can legally replace a worn washer yourself because it counts as maintaining an existing fixture. Installing a new tap is a different matter — that requires a licensed plumber.
Legal in Victoria — this is maintenance, not installation
Checked as at September 2026. Rules and prices change — confirm anything you are about to act on.
What you need
- Replacement washers and O-rings to suit your tap
- Adjustable spanner or tap spanner
- Flat screwdriver
- Cloth to protect the chrome
- Plumber's grease
Step by step
Turn the water off and drain the line
Isolate at the stop tap under the basin if there is one, otherwise at the water meter. Open the tap fully and let it drain. Then plug the basin — this is the step everyone skips and it is how the small brass screw ends up in the trap.
Remove the handle and headgear
Prise off the button or cap on top, undo the screw beneath, and lift the handle off. Wrap a cloth around the chrome shroud to protect it, then undo the headgear with a spanner, turning anticlockwise.
Replace the washer and O-ring
The washer is on the bottom of the headgear, held by a small nut or push-fit. Take the old one to the hardware shop rather than guessing the size. While it is apart, replace the O-ring on the spindle too — it is usually the cause of a leak from around the handle rather than the spout.
Check the seat
Look into the tap body at the brass seat the washer presses against. If it is pitted or scored, a new washer will drip again quickly. Reseating tools exist but at this point most people are better off replacing the tap — which means calling a plumber.
Reassemble and turn on slowly
Grease the thread lightly, reassemble finger tight then a gentle nip with the spanner. Overtightening cracks the seat. Turn the water back on slowly and check for leaks at the handle and under the basin.
Common mistakes
- Not plugging the drain before starting
- Overtightening the headgear and damaging the seat
- Guessing the washer size instead of taking the old one in
- Forgetting the O-ring, then wondering why it still weeps at the handle
When to stop and call someone
A tempering valve or thermostatic mixing valve is not an ordinary tap and is expressly excluded from the homeowner exemption — if the fitting is on the hot line near the hot water unit, leave it. If the tap is a mixer or wall-mounted, if the seat is damaged, if you need to remove the tap body, or if anything needs cutting or re-soldering — that is licensed plumbing work in Victoria. Unlicensed plumbing can void your home insurance if it causes damage, and the penalties are serious. If you are unsure, ask a licensed plumber — most will quote a washer job over the phone.
This guide is general information, not advice for your particular house. Rules change — check the current position with the Building and Plumbing Commission, Energy Safe Victoria and WorkSafe Victoria before you rely on it. Plumbing, gas and electrical work must be done by a licensed practitioner. If your home was built or last renovated before 1990, assume asbestos until it is ruled out — see what a strip-out finds.