How to Fix a Leaking Tap in Australia (Step-by-Step Guide)

DIY Plumbing April 2026 8 min read By Trusted Plumbers Editorial

A dripping tap wastes up to 20,000 litres of water per year. That maddening drip isn't just an annoyance — at typical Australian water rates, it adds up to $20–$60 annually in wasted water. The good news? Most leaking taps are fixable in under an hour with a few basic tools and a $5–$15 washer kit from Bunnings. This guide walks you through diagnosing the leak and fixing it yourself.

Why Is Your Tap Leaking? (Diagnose First)

Before you reach for a spanner, it's worth identifying what type of tap you have and where the drip is coming from. The fix varies significantly depending on the tap style and the location of the leak.

Common causes

  • Worn washer — The most common cause in older taps. The rubber washer at the base of the tap spindle presses against the valve seat to stop water flow. Over time it hardens, compresses, or tears. Result: a drip from the spout.
  • Worn O-ring — A small rubber ring that seals the tap spindle. When it deteriorates, you get drips from the spout base or from around the handle rather than from the spout tip.
  • Ceramic cartridge failure — Quarter-turn (lever) taps use a ceramic disc cartridge instead of a rubber washer. When the discs crack or the cartridge seals fail, the tap drips or becomes hard to turn.
  • Faulty valve seat — The valve seat is the brass fitting inside the tap body that the washer presses against. If it's scored or corroded, even a brand-new washer won't stop the drip.
Tap type Likely cause Typical fix
Traditional (capstan/cross-head) Worn washer or O-ring Washer/O-ring replacement
Quarter-turn lever tap Ceramic cartridge failure Cartridge replacement
Mixer tap (single handle) Cartridge or internal valve Cartridge replacement (often brand-specific)
Drip from handle base Worn O-ring on spindle O-ring replacement
Drip from around body Loose packing nut or failed body seal Retighten or replace packing

What You'll Need (Tools & Parts)

You don't need a fully stocked tradie toolbox. Here's what you'll need for a standard washer replacement or cartridge swap.

Tools

  • Adjustable spanner or shifting spanner
  • Phillips head screwdriver
  • Flathead screwdriver (for removing decorative caps)
  • Tap reseating tool (optional — only needed if the valve seat is damaged)
  • Small bowl or towel to catch residual water

Parts

  • Tap washer kit — most kits include several sizes and cost $5–$10 at Bunnings
  • O-ring kit — a multi-size pack covers most household taps
  • Replacement ceramic cartridge — for quarter-turn taps; take note of the brand and model if possible
  • Plumber's grease (silicone-based) — a small tub costs around $5 and makes reassembly easier
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Where to buy: Bunnings, Reece Plumbing, Tradelink, or any plumbing supply store. If you can, take the old washer or cartridge with you to match the size. The total cost of parts is typically $10–$25 for a DIY fix.

Step-by-Step: Fix a Dripping Tap (Washers)

This method applies to traditional taps with a capstan (cross-head) or wheel-style handle. It covers both cold and hot taps.

1

Turn off the water supply

Locate the isolating valve under the sink (a small oval slot or flat-head screw fitting on the water line). Turn it a quarter-turn clockwise to shut off flow. If there's no isolating valve, turn off the main stopcock at your water meter. Check that the water is off by turning the tap on — only residual water should come out.

2

Open the tap fully to drain residual water

Turn the tap handle to the fully open position. This releases any remaining water pressure in the line and makes the job cleaner and easier to work on. Place a towel or small bowl under the tap to catch any drips.

3

Remove the tap handle

Look for a small decorative cap on top of the handle — prise it off gently with a flathead screwdriver to reveal the retaining screw underneath. Undo that screw (usually Phillips head), then lift or pull the handle straight off. Some older handles may be tight; a gentle wiggle while pulling up usually frees them.

4

Undo the headgear nut with a spanner

The headgear nut is the large brass nut that holds the tap internals in place. Turn it anti-clockwise with your adjustable spanner. If it's stiff, hold the tap body firmly with your free hand to avoid stressing the pipes. Remove the nut and set it aside.

5

Remove the jumper valve and inspect the washer

With the headgear nut removed, you can pull out the jumper valve — the spindle with the washer attached at the bottom. Examine the washer: if it's flattened, cracked, or hardened, it needs replacing. While you're here, also check the O-ring on the spindle body for signs of wear.

6

Replace the washer and O-ring

Most washers are held on by a small brass nut at the base of the jumper valve — undo it, pop off the old washer, and press on the new one. Match the size carefully (12mm and 15mm are the most common in Australian homes). Apply a thin smear of plumber's grease to the new O-ring before fitting. Replace both while you have the tap apart — it's cheap insurance.

7

Reassemble, restore water, and test

Reassemble in reverse order: replace the jumper valve, thread the headgear nut back on hand-tight then snug it with the spanner (don't overtighten — brass strips easily), reattach the handle, and replace the decorative cap. Slowly turn the isolating valve back on. Turn the tap off and watch for leaks at the spout and around the handle. A successful fix means no dripping within 60 seconds of turning off.

Step-by-Step: Fix a Quarter-Turn (Ceramic) Tap

Ceramic disc taps are common in modern Australian kitchens and bathrooms. They use a cartridge containing two ceramic discs rather than a rubber washer. When they fail, the tap either drips, becomes stiff, or won't close fully.

  1. Turn off the water supply at the isolating valve, as above.
  2. Remove the tap handle (usually a grub screw on the side or underneath, or a top screw under a cap).
  3. Unscrew the cartridge retaining nut anti-clockwise.
  4. Pull the cartridge straight out — note its orientation before removing.
  5. Take the old cartridge to a plumbing supply store to match it, or photograph the brand and model number on the side.
  6. Insert the new cartridge in the same orientation, replace the retaining nut, and reassemble the handle.
  7. Restore water supply and test.
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State regulation note: Replacing a ceramic cartridge is generally considered legal DIY plumbing across Australia. However, if the tap is connected to a hot water system or if any pipework needs to be moved or modified, that work requires a licensed plumber. When in doubt, check your state's fair trading or plumbing regulation website.

How Much Does It Cost to Fix a Leaking Tap?

Whether you DIY or call a plumber depends on the complexity of the repair and your confidence level. Here's a realistic cost comparison.

Fix type DIY cost Plumber cost
Washer replacement $5–$15 $120–$180
O-ring replacement $5–$15 $120–$180
Ceramic cartridge replacement $15–$40 $150–$250
Complete tap replacement $50–$200 $200–$450
Valve seat regrind $20–$50 (tool hire) $150–$250

Legal DIY reminder: A leaking tap is legal DIY in all Australian states and territories. You don't need a plumber for a basic washer or cartridge swap. However, any work on hot water systems, gas lines, or moving pipes requires a licensed plumber — and attempting it unlicensed can void your home insurance.

When to Call a Plumber

Most leaking taps are straightforward DIY jobs, but there are situations where it's worth calling in a professional. Don't feel defeated — even experienced DIYers know when to hand something over.

  • The valve seat is damaged. If the seat is scored, pitted, or corroded, a new washer won't seal against it. Reseating requires a tap reseating tool and some practice — or simply call a plumber.
  • Water hammer is causing the drip. If you hear a banging or thudding noise when you close the tap, there may be a pressure issue in your water lines. This is a plumbing system problem, not just a worn part.
  • Multiple taps are dripping simultaneously. If several taps around the house start leaking at once, it may indicate a water pressure problem or an issue with the main supply — worth a plumber's diagnosis.
  • There's water damage around the tap base. Staining, swelling, or soft cabinetry around the tap suggests a longer-term slow leak that may have caused hidden damage. A plumber can assess the extent.
  • It's a mixer tap with complex internals. Some brand-specific mixer cartridges are tricky to source and require precise installation. If you can't identify the cartridge model, a plumber with trade accounts can usually source and fit it faster.

Frequently Asked Questions

Yes, for most basic repairs. Replacing washers, O-rings and ceramic cartridges is legal DIY in all Australian states. You don't need a licensed plumber for these tasks — just turn off the water supply first. If the repair involves moving pipes, connecting to a hot water system, or any gas work, that's a job for a licenced tradesperson.
A tap dripping once per second wastes approximately 12,000–20,000 litres of water per year. At typical Australian water rates, that's $20–$60 per year in wasted water — plus the cost of the drip itself. Over five years, a single unrepaired dripping tap can waste more than 75,000 litres.
Most Australian household taps use either a 12mm or 15mm washer. Take the old washer to Bunnings or a plumbing supply store to match it. Universal washer kits usually include multiple sizes, so buying a kit rather than a single washer is often the smarter choice — it covers you for most taps in the house.
The most likely cause is a damaged valve seat — the brass fitting the washer presses against. If the seat is scored or corroded, a new washer won't seal properly. You'll need to regrind the seat with a reseating tool, or call a plumber. Less commonly, the washer may be the wrong size, or the headgear nut may not be tight enough.
For a basic washer replacement, allow 30–60 minutes including locating the right parts. First-timers often take a bit longer, especially if the tap is stiff or the washer is awkward to access. Ceramic cartridge replacements are usually faster — around 20–30 minutes once you have the right part in hand.
Not always. Most modern Australian homes have isolating valves under the sink that let you shut off water to just that tap. If there's no isolator, you'll need to turn off the main stopcock at the water meter. It's usually located at the front of the property near the boundary, inside a small concrete or plastic box set into the ground.