How to Fix a Leaking Tap (UK DIY Guide)
A leaking tap is one of the most common household problems in UK homes. Even a slow drip can waste water and increase your utility bills over time.
This step-by-step DIY guide explains how to fix a leaking tap safely, whether you have a traditional washer tap or a modern ceramic cartridge tap.
Tools You’ll Need
- Adjustable spanner
- Screwdriver (flathead or Phillips)
- Allen key (if required)
- Replacement washer or cartridge
- Cloth or towel
- PTFE tape (optional)
Materials Required
- Replacement tap washer (for compression taps)
- Replacement ceramic cartridge (for mixer taps)
- Silicone grease (optional)
Step 1: Turn Off the Water Supply
Locate the isolation valve under the sink and turn it clockwise to shut off water.
If there is no isolation valve, turn off the mains water supply.
Turn the tap on fully to drain any remaining water.
Step 2: Remove the Tap Handle
Use a screwdriver to remove the decorative cap.
Unscrew the handle fixing screw.
Lift off the tap handle to expose the valve mechanism.
Step 3: Identify the Tap Type
There are two common types:
Compression tap (older style)
Uses a rubber washer at the base.
Ceramic cartridge tap (modern mixer tap)
Uses a ceramic disc cartridge.
Identifying the type determines which part needs replacing.
Step 4: Replace the Washer (Compression Tap)
Use a spanner to unscrew the valve.
Remove the old rubber washer at the base.
Fit the new washer securely.
Reassemble the tap and tighten carefully.
Step 5: Replace the Cartridge (Mixer Tap)
Unscrew the retaining nut holding the cartridge.
Remove the old cartridge.
Insert the new one in the same orientation.
Reassemble and tighten securely.
Step 6: Turn Water Back On
Slowly turn the water supply back on.
Test the tap.
Check for leaks around the base and handle.
Common Mistakes to Avoid
- Forgetting to turn off the water
- Overtightening fittings
- Using the wrong washer size
- Forcing corroded parts
- Reassembling parts in the wrong order
Take photos during disassembly to avoid confusion.
When to Call a Professional
You should consider calling a plumber if:
- The tap is heavily corroded
- The valve body is damaged
- Leaks continue after part replacement
- You cannot isolate the water supply
- Pipework beneath the sink is leaking
For typical UK repair pricing, see our Plumbing Repair Cost Guide.