A dripping tap is more than an irritation – it’s wasted water and money. Left alone, that persistent drip can even damage fittings or stain sinks. Fortunately, replacing a tap washer is one of those straightforward DIY fixes that doesn’t demand a professional. With the right tools and a careful approach, you can sort it in under an hour. But there’s a method to it, and rushing risks scratches or worse, a leak that’s harder to control.
What Causes Tap Washers to Fail?
Most traditional taps rely on a small rubber or ceramic washer that presses against a valve seat to stop water flow. Over time, friction and mineral deposits wear down that washer. Not only does it lose its seal, but it starts to harden or crack, which means every twist of the tap worsens the problem. Hard water areas see this more often – limescale eats into both the washer and the seating beneath it.
And then there’s the human factor. Over-tightening a tap handle might seem like a way to silence a drip, yet it accelerates washer damage. It’s a simple part, but it’s doing all the work against the water pressure behind it.
How to Change a Tap Washer Step by Step
There’s no complicated skill involved, but preparation matters. Make sure you have a replacement washer that matches your tap type and size – there’s no universal fit. For kitchen and bathroom taps, washers typically measure between 8mm and 24mm, while mixer taps often have smaller inserts. If you’re unsure, remove the old one first and take it to a hardware shop.
Here’s a quick checklist of what you’ll need:
- Adjustable spanner or tap wrench
- Flathead and Phillips screwdrivers
- Replacement washer (and possibly an O-ring)
- PTFE tape
- Old towel or cloth to protect chrome
1. Isolate the Water Supply
Not only is this essential for safety, but it prevents a surprise burst of water mid-repair. Find the isolation valve under the sink or use the main stopcock. Turn on the tap to drain any remaining water in the pipes. A towel underneath the tap base is smart – any leftover drips are caught rather than pooling on the worktop.
2. Remove the Tap Handle
Mixer taps and pillar taps differ slightly, but most handles are held by a small screw hidden under a cap or decorative cover. Gently lever the cap off with a screwdriver and undo the screw. If the handle resists lifting, a gentle wiggle rather than brute force avoids scratching the chrome.
3. Access the Valve and Washer
Beneath the handle lies the brass body of the tap, often called the spindle or valve. Use your spanner to loosen it – steady pressure, not jerky twists, works best. Once the valve is free, inspect the base. You’ll see the old washer held in place by a small screw. Unscrew it and check the condition of both washer and seating.
4. Fit the New Washer
Place the new washer exactly where the old one sat. If the seating inside the tap looks rough or pitted, a reseating tool may be necessary, but for most domestic taps a fresh washer is enough. A quick wrap of PTFE tape around the valve’s threads ensures a snug, leak-resistant reassembly.
5. Reassemble the Tap
Reverse the steps – valve back in place, handle reattached, cap replaced. Open the isolation valve slowly, allowing the tap to refill without a sudden surge. Test it by turning the tap on and off a few times. A silent, drip-free shut-off means you’ve done it right.
How to Change a Washer on a Mixer Tap
Mixer taps can be trickier because they often use ceramic disc cartridges instead of rubber washers. If that’s the case, you’ll need to replace the cartridge rather than just a washer. But if it’s a traditional mixer with washers, the steps are the same – just remember the components might be smaller and tighter.
For a detailed comparison, check our guide on [how to fix a dripping tap at home].
When to Call a Professional
Some taps are simply awkward – hidden screws, seized parts, or damage you can’t see until it’s taken apart. If you’ve tried and failed or suspect the valve seat itself is worn, there’s no shame in calling an expert. You can always get fast plumbing help instead of risking a bigger leak.
The Bottom Line
Changing a tap washer isn’t complicated, but it pays to be methodical. The process is mostly about knowing where each component sits and reassembling everything as it was. Not only is it a quick fix for drips, but it’s also a small way to cut water bills and avoid unnecessary waste. And if the problem persists even after a washer swap, it’s likely pointing to deeper wear in the tap – something better left to professional hands.
