That dripping tap in the bathroom. The slight weep from around the base of the kitchen mixer. The outdoor tap that gets worse every month. In the vast majority of cases, these problems share the same root cause: a worn rubber washer or O-ring that costs under $1 to replace.
The difference between a Gold Coast homeowner who fixes a dripping tap in 20 minutes and one who calls a plumber for a $150 call-out is usually nothing more than whether they had the right $0.80 rubber washer on hand.
This guide covers exactly what washers and O-rings to stock, how to identify which one has failed, and how to replace them on the most common household taps.
Why Washers and O-Rings Fail
Both components are made from rubber or synthetic rubber compounds (EPDM or neoprene) that degrade over time through:
- Constant compression — every time you close a tap, the washer is compressed against the seat. Thousands of repetitions cause it to harden, crack, or deform.
- Heat and UV exposure — hot water accelerates rubber degradation. Gold Coast's subtropical sun degrades outdoor tap components faster than cooler climates.
- Mineral deposits — Gold Coast tap water contains calcium and magnesium. Over time, scale builds up on washers and seats, reducing the seal quality and accelerating wear.
- Chemical exposure — cleaning products and some water treatment chemicals degrade rubber compounds over years.
Most washers and O-rings in a typical Gold Coast home need replacement every 5–10 years, depending on usage and water chemistry.
Washers vs. O-Rings: What's the Difference?
Tap washers
are flat or slightly domed rubber discs that sit at the end of the tap spindle (the internal rotating component). When the tap is fully closed, the washer is pressed firmly against the valve seat, blocking the flow. A worn washer creates a drip from the spout when the tap is off.
O-rings
are rounded rubber rings (circular cross-section) that sit in grooves on the tap spindle or body and create a seal against the tap housing. When an O-ring fails, water leaks around the base of the tap or around the spindle — not from the spout.
Simple diagnostic:
- Drip from the spout when tap is off → tap washer failure
- Leak around the spindle or base of tap → O-ring failure
What to Stock: The Essential Assortment
A basic washer and O-ring kit to handle 95% of household tap failures:
Tap Washers
- 13mm (½ inch) flat jumper washers — the most common size for kitchen and bathroom taps (both body and outlet)
- 19mm (¾ inch) flat jumper washers — common in older-style bath and laundry taps
- 13mm dome washers — used in some cold water taps for a better seal
- Fibre washers (various) — for some garden tap and hose fitting connections
Look for: "Assorted tap washer pack" at any hardware store. Typically contains 30–50 washers in multiple sizes for $6–$12.
O-Rings
O-rings are categorised by their internal diameter (ID) and cross-section diameter. For household taps, stock these:
- Sizes 009–015 (BS standard) — covers the majority of small tap spindle O-rings
- Sizes 016–022 — for larger mixer tap bodies and some showerhead connections
- Silicone O-rings — for hot water applications (standard rubber degrades faster in hot water)
Look for: "O-ring assortment kit" from a hardware or plumbing supplier. Kits with 200–300 assorted O-rings cost $15–$25 and will last years.
Also Useful: Tap Spindle Kits
Many hardware stores sell brand-specific spindle/cartridge kits for common tap brands (Caroma, Dorf, Methven, Mizu). If your tap is a known brand, the entire internal assembly — spindle, washer, and O-ring — can be replaced as a single unit, which is often easier and more reliable than replacing individual components.
How to Replace a Tap Washer: Step-by-Step
You'll need:
Adjustable wrench, flathead screwdriver, the correct replacement washer, PTFE tape.
- Turn off isolation valve under the sink or at the main
- Open the tap fully to relieve remaining line pressure
- Remove the tap handle — usually one screw concealed under the decorative cap (pry off cap with a flathead screwdriver)
- Unscrew the packing nut (the hexagonal nut below the handle) with your adjustable wrench
- Pull out the spindle — it threads out once the nut is loose
- Find the washer — at the bottom of the spindle, held by a small brass screw
- Remove the old washer — unscrew the brass screw, remove the failed washer
- Install the new washer — press it firmly into place, replace the brass screw
- Inspect the valve seat — if it looks pitted or corroded, it may need re-grinding. If it looks smooth and clean, reassemble.
- Reassemble in reverse order. Don't overtighten — finger tight plus a quarter turn with the wrench.
- Turn supply back on and test
When the Washer Fix Doesn't Stop the Drip
If replacing the washer doesn't cure the drip, the valve seat is likely damaged. The seat is the brass ring inside the tap body that the washer presses against. A worn, pitted, or corroded seat means even a new washer won't seal.
Options:
- Re-grind the seat using a tap seat grinder (a small specialised tool available from hardware stores) — restores a smooth seating surface
- Replace the seat — some taps have removable seats that can be unscrewed and replaced
- Replace the tap — if the body is old or heavily corroded, a full tap replacement by a licensed plumber is often the most cost-effective long-term solution
When to Call a Gold Coast Plumber
Call a plumber if:
- The tap body or fittings are visibly cracked or corroded
- The isolation valve under the fixture won't turn off fully (replace before the washer fix)
- Water hammer (loud banging in pipes when the tap closes) persists after washer replacement — this usually indicates pressure issues or loose pipe supports
- Hot water tap repairs (supply side is under higher pressure and temperature)
- Any mixer tap with a ceramic cartridge rather than a traditional spindle — these require specific cartridges, not standard washers
Call Coastal Plumbing Professionals on 1300 590 085 for prompt tap repair across all Gold Coast suburbs.
Frequently Asked Questions
How do I know what size washer I need?
Bring the old washer to a hardware store and match it. If you don't have the old one, bring a photo of the tap spindle — hardware staff can usually identify the correct washer from the spindle type.
Can I fix every dripping tap with a washer replacement?
No — modern mixer taps use ceramic disc cartridges rather than rubber washers. These cannot be repaired with standard washers. They need a brand-specific cartridge replacement or, if the cartridge is unavailable, a new tap.
How do I know if it's an O-ring or a washer?
If the tap drips from the spout when turned off, it's the washer. If it leaks around the spindle or at the base of the tap body, it's an O-ring.
Are all tap washers the same?
No — while 13mm flat jumper washers cover most common cases, some taps use cone washers, dome washers, or fibre washers. An assortment pack is the best insurance.
Resources
- Standards Australia AS/NZS 3718 — Water supply — Tap ware standards
- QBCC Queensland Building and Construction Commission — QLD plumbing licencing and homeowner work limits
- Master Plumbers Australia — Industry guidance on tap maintenance
