How to Replace a Tap Washer (Step-by-Step Guide)

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If you've got an older-style tap with a traditional turn handle and it's been dripping steadily, there's a good chance a worn washer is to blame. It's one of the simplest and cheapest plumbing repairs there is, and most homeowners can do it themselves in well under an hour with a basic toolkit.

This guide walks through exactly how to replace a tap washer step by step, what tools you'll need, and how to tell if a washer is really the problem before you start pulling the tap apart.

Is Your Tap a Washer Type?

Tap washer replacement applies to compression taps, the kind with a traditional round or cross handle you turn to open and close. If your tap has a single lever you lift or push to control water flow, it likely uses a cartridge instead, which is a different repair.

Signs a washer is worn

• Steady drip from the spout when the tap is fully closed
• You need to turn the handle further than usual to stop the drip
• Dripping has gradually worsened over weeks or months
• The tap is a compression style with a traditional handle

Tools You'll Need

• Adjustable spanner or wrench
• Flathead screwdriver
• Replacement washer (take the old one to the hardware store to match it exactly)
• Plumber's tape
• A cloth or plug for the drain

How to Replace a Tap Washer

1. Turn off the water supply. Find the isolation valve under the sink, or the property's main shut-off if there's no isolation valve, and turn it off fully.
2. Open the tap. With the supply off, turn the tap handle to the open position to release any remaining pressure in the line.
3. Plug the drain. Cover the plughole with a cloth so the small screws and washer don't disappear down the sink while you work.
4. Remove the handle. Most handles have a small screw hidden under a cap on top. Pop the cap off with a flathead screwdriver, then unscrew and lift the handle away.
5. Unscrew the retaining nut or headgear. Use an adjustable spanner to loosen the nut holding the tap's internal spindle assembly in place, then lift it out.
6. Locate the washer. It's a small rubber disc at the base of the spindle, held in place by a tiny screw or nut.
7. Remove the old washer. Unscrew or pry it off carefully, noting its size and shape for an exact match.
8. Fit the new washer. Press or screw the new washer into place, making sure it sits flush and secure.
9. Check the valve seat. While it's apart, inspect the valve seat inside the tap body for pitting or corrosion. If it looks rough or damaged, a new washer alone won't stop the drip.
10. Reassemble the tap. Screw the spindle assembly back in, refit the handle, and remove the cap.
11. Turn the water back on slowly and check for leaks at the spout and around the handle.

Why the Drip Might Continue After a New Washer

If you've fitted a new washer and the tap still drips, the most likely explanation is a damaged valve seat. The washer needs a smooth surface to seal against, and if that seat is corroded or pitted, even a brand-new washer won't stop water seeping through.

Other possibilities include an incorrectly sized washer, a washer fitted the wrong way around, or a worn O-ring elsewhere in the tap assembly that's unrelated to the washer itself.

When to Call a Plumber

Replacing a tap washer is one of the more DIY-friendly plumbing jobs, but call a licensed plumber if:

• The tap still drips after fitting a correctly sized new washer
• The valve seat looks corroded, pitted or damaged
• The tap handle is seized and won't come apart safely
• You're dealing with an older tap where parts are hard to source
• The leak is coming from inside the wall rather than the tap itself

If your Gold Coast home has a tap that won't stop dripping no matter what you try, get in touch with our team for a fast, upfront repair.

Preventing Washer Wear

• Turn taps off gently. Over-tightening is one of the biggest causes of premature washer wear
• Replace washers proactively every few years on high-use taps like the kitchen sink
• Address small drips early, since a worn washer left in place can damage the valve seat underneath
• Consider upgrading to ceramic disc taps during a bathroom or kitchen renovation, which don't use washers at all

Final Thoughts

Replacing a tap washer is a straightforward, inexpensive fix for one of the most common causes of a dripping tap, and most Gold Coast homeowners can do it themselves with basic tools. If a fresh washer doesn't stop the drip, the valve seat underneath is the next thing to check, and that's usually where a plumber's help becomes worthwhile.

Call Coastal Plumbing Professionals on 1300 590 085 if your tap is still dripping after a washer replacement.

Frequently Asked Questions

How do I know what size washer to buy?
Take the old washer with you to the hardware store, or your local plumbing supplier, to match the exact size and shape. Washers vary between tap brands and models.

Can I use the same washer on a mixer tap?
No. Mixer taps with a single lever handle typically use a cartridge, not a washer. Trying to fit a washer to a cartridge tap won't work.

Why does my tap need turning further and further to stop dripping?
This is a classic sign of a worn washer. As it flattens with use, you need more pressure to force a seal, which is a good indicator it's time to replace it.

Is it normal for the valve seat to wear out too?
Yes, especially in older homes or areas with harder water. If a new washer doesn't stop the leak, the seat is the next most likely cause.

How often should tap washers be replaced?
There's no fixed schedule, but high-use taps like kitchen sinks often need a new washer every two to three years, while low-use taps can go much longer.

Resources

1. WaterMark Certification Scheme | Australian Building Codes Board
2. Save water at home | Queensland Government
3. AS/NZS 3500 Plumbing and Drainage Standards