Why Taps Drip

A dripping tap wastes up to 20,000 litres of water per year and adds to your water bill. Most drips have one of two causes: a worn rubber washer (in traditional compression taps) or a worn cartridge (in modern single-lever and ball taps). Identifying which type you have determines the fix.

Identify Your Tap Type

  • Compression tap: Two separate hot and cold handles that turn multiple times from fully open to closed. Very common in older Australian homes. The drip is usually fixed by replacing a rubber washer — a $2 part.
  • Cartridge tap: Single lever or handles that turn only a quarter or half turn. Used in most modern tapware. Requires replacing the cartridge — $15–50 depending on the brand.
  • Ball tap (mixer): Single handle that rotates in multiple directions. Common in kitchens. Requires a ball valve repair kit.

Fixing a Compression Tap (Worn Washer)

  1. 1

    Turn off the water supply

    Close the isolation valve under the sink (turn clockwise). Turn the tap fully on to release remaining water pressure. If there is no isolation valve, turn off the main water supply to the house.

  2. 2

    Remove the tap handle

    Prise off the decorative cap on top of the handle with a flat screwdriver. Remove the screw underneath. Pull the handle straight up — it may need gentle wiggling if corroded.

  3. 3

    Unscrew the packing nut and remove the stem

    Use an adjustable spanner to unscrew the packing nut (the large hexagonal fitting below the handle). Turn anticlockwise. Once the nut is off, the stem (the threaded rod) can be unscrewed and removed.

  4. 4

    Replace the rubber washer

    At the bottom of the stem you will find a rubber washer held by a small brass screw. Remove the screw and washer. Take the old washer to a hardware store to match the size exactly. Fit the new washer and screw it in place.

  5. 5

    Reassemble and test

    Screw the stem back in, replace the packing nut, refit the handle and decorative cap. Turn the water supply back on slowly. Test the tap — the drip should have stopped completely.

Fixing a Cartridge Tap

The process is similar — remove the handle (usually one Allen key screw on the side or a screw under the cap), then the retaining clip or nut, and slide out the cartridge. Take it to a plumbing supplier to match exactly — cartridges are brand-specific. Slide in the new cartridge in the correct orientation, reassemble and test.

Also check the O-ringsWhile you have the tap disassembled, check the O-rings on the stem — small rubber rings that seal against leaks from the base of the handle. If they are cracked or flattened, replace them at the same time. O-rings are a few cents each and are a common secondary cause of dripping and handle leaks.

Frequently Asked Questions

A drip from the spout when the tap is off is almost always a worn washer or cartridge at the valve seat. This is the standard repair described above. If you have replaced the washer and the drip continues, the valve seat itself may be pitted or damaged — it can be reground with a seat grinder tool or the tap body may need replacing.
Yes — a leak at the base of the handle is usually caused by worn O-rings or a worn packing nut seal. This is typically a separate issue from a dripping spout. Disassemble the handle and replace the O-rings and packing nut washer. Both repairs are often worth doing at the same time since you are already disassembling the tap.