How to Fix a Leaking Tap — Washer Replacement Guide

Updated July 2026 · 7 min read · Geelong Emergency Plumbing

A dripping tap is one of those problems with an exact known cost: a tap dripping once per second wastes roughly 12,000 litres a year — that's about $30–50 in water bills annually, which is the universe gently suggesting you spend twenty minutes and five dollars on a washer. Most tap leaks in Australian homes have one of two causes: a worn rubber washer (compression taps — the older kind with a wheel you turn) or a worn ceramic cartridge or O-ring (mixer and quarter-turn taps). Here's how to fix both, step by step.

Before You Touch Anything: Turn Off the Water

Find the isolation valve for the tap — usually a small oval-head valve under the sink or behind the wall access panel. Turn it clockwise until it stops. If there's no isolation valve (common in older homes), you'll need to isolate at the water meter — our water mains guide covers finding yours. Once off, turn the tap on to release pressure and drain the remaining water in the line. A step so important and so often skipped that plumbers have a phrase for homeowners who learned it expensively.

Identify Your Tap Type

Compression tap (older, typically separate hot and cold): you turn a wheel or cross-head handle several times to open and close. The valve uses a rubber washer that presses against a seat to stop flow — when the washer wears, it doesn't seal completely. This is the classic dripping tap, and the repair is a washer replacement.

Ceramic disc / quarter-turn tap (modern, single-lever or quarter-turn): opens fully in a quarter turn. Uses a ceramic disc cartridge rather than a rubber washer. Drips are less common but when they occur usually mean a worn O-ring, a cracked ceramic disc, or grit in the cartridge. Cartridge replacement is the repair.

Mixer tap (single lever, hot and cold combined): a ball valve or cartridge inside. Drips or leaks at the spout usually mean the cartridge; leaks around the base of the spout usually mean O-rings on the mixing body.

Fixing a Compression Tap — Washer Replacement

1. Tools: adjustable wrench, flathead and Phillips screwdrivers, replacement washers (take the old one to the hardware store — sizes vary), penetrating oil for stuck parts, and a cloth to protect chrome finishes from the wrench.
2. Remove the handle: pop off the decorative cap (hot or cold indicator) — usually pries off with a flathead. Remove the screw underneath. Lift or pull the handle off.
3. Remove the packing nut: this is the large hex nut directly below the handle. Use the wrench with a cloth wrapped around the hex to avoid scratching. Turn anticlockwise.
4. Extract the spindle: unscrew and lift the whole spindle assembly out of the tap body.
5. Replace the washer: at the base of the spindle is the rubber washer, held by a brass screw. Unscrew it, pull the old washer, push the new one in (same size, same profile), replace the screw.
6. While you're in there: check the seat — the brass surface the washer presses against. If it's pitted or scored, a tap reseater tool ($15–$25) can smooth it; a pitted seat chews through new washers quickly. Also replace the O-rings on the spindle if they look flat or cracked — they prevent leaks around the stem, not the spout.
7. Reassemble in reverse, hand-tight plus a firm quarter-turn with the wrench. Restore the water supply and test.

Fixing a Quarter-Turn or Mixer Tap — Cartridge Replacement

1. Same water-off first step.
2. Remove handle: decorative cap, screw underneath, handle off.
3. Some cartridge taps have a retaining clip or nut above the cartridge — remove it.
4. Pull the cartridge straight up (or use cartridge-puller pliers for stuck ones). Note the orientation before it comes out — cartridges are direction-specific.
5. Take the old cartridge to a plumbing supplier. Most tap manufacturers have spare cartridges; independent suppliers stock common sizes. Fit the replacement in the same orientation.
6. Reassemble, restore water, test for drips and for the hot/cold direction being correct.

When DIY Tap Repair Isn't the Answer

The repair just described is legal DIY in Victoria — homeowners can replace washers, O-rings and tap cartridges on existing taps. What tips it into licensed-plumber territory: replacing the tap itself (involves connection to water supply lines), anything involving pipework or soldering, or a dripping tap that persists after two washer replacements (usually a pitted seat or damaged spindle requiring a more involved repair or new tap). Licensed work is also required if the isolation valve fails while you're working — another good reason to know where your mains is before you start.

The Cost Case

A washer kit: $5–$15. A complete DIY repair: 30–60 minutes. Plumber to do it: $100–$250 depending on access and whether it escalates to a tap replacement. For a straightforward washer-type drip, DIY is justified and the skill transfers to every other tap in the house. For quarter-turn cartridge taps in older or awkward locations where the cartridge is seized or the seat is damaged, a plumber's visit is quick and the total bill is modest — far less than a year of ignoring the drip on a damaged-seat scenario where washers keep failing.

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