How to Fix a Leaking Tap Yourself (Before Calling a Plumber)

A dripping tap is one of those things that starts as a mild annoyance and gradually becomes the background soundtrack to your life. Drip. Drip. Drip. You lie in bed at night convinced it’s getting louder, and you keep telling yourself you’ll sort it tomorrow.

Here’s the good news: fixing a leaking tap is one of the simplest plumbing jobs you can do yourself. In most cases, it takes 20–30 minutes, costs under £10 in parts, and requires no specialist tools. Compare that to calling a plumber — minimum callout charge of £60–80 where I am — and it’s well worth learning.

This guide covers the four main tap types you’ll find in UK homes, how to diagnose the problem, and step-by-step instructions for fixing each one.

Identify Your Tap Type First

Before you grab a spanner, you need to know what you’re working with. The fix depends entirely on the type of tap, and using the wrong approach will leave you with parts scattered across the kitchen and water still dripping.

Compression Taps (Traditional)

These are the classic taps with separate hot and cold handles that you screw closed. They’re common in older UK homes — if your house was built before the 1990s, there’s a good chance you’ve got compression taps somewhere. They work by pressing a rubber washer onto a valve seat. When the washer wears out, water seeps past and you get a drip.

How to identify: You turn the handle multiple times to close it, and you can feel it tighten. Two separate taps for hot and cold is a strong indicator.

Ceramic Disc Taps

These are the most common modern tap type in the UK. They use two ceramic discs that slide across each other — when the holes align, water flows. They’re quarter-turn taps, meaning you only rotate the handle 90 degrees from off to full. They last much longer than compression taps but aren’t immune to failure.

How to identify: Quarter-turn operation. The handle moves from off to full in a short arc.

Ball Taps

Single-lever mixer taps that use a rotating ball mechanism inside. More common in American-style fixtures but you’ll find them in some UK kitchens. The ball has slots that control water flow and temperature based on the lever’s position.

How to identify: Single lever that moves up/down for flow and left/right for temperature.

Cartridge Taps

Similar to ball taps in that they’re often single-lever, but instead of a ball, they use a replaceable cartridge. Many modern mixer taps use this design. When they fail, you replace the entire cartridge rather than individual parts.

How to identify: Single lever, but the internal mechanism is a self-contained cartridge. You often can’t tell until you open it up — if there’s no ball, it’s a cartridge.

Tools You’ll Need

The beauty of this job is that you probably already own everything you need:

• Adjustable spanner — one medium-sized (200mm) covers most taps
• Flathead and Phillips screwdrivers
• Allen keys — some modern taps use grub screws
• Plumber’s tape (PTFE tape) — for reassembly
• Old towel or cloth — to line the sink and catch dropped parts
• Replacement parts — washer, O-ring, or cartridge depending on your tap type

Top tip: Put the plug in before you start dismantling anything. Tiny screws and O-rings love to bounce straight down the plughole. Ask me how I know.

Step 1 — Turn Off the Water Supply

This seems obvious, but you’d be amazed how many people skip this step and end up with a kitchen geyser. There are three places to look:

1. Isolation valves under the sink — These are small valves on the pipes directly below your tap. Turn the screw slot so it sits across the pipe (perpendicular) to shut off. This is the best option as it only affects the one tap.
2. Service valve — Usually under the kitchen sink or near the boiler. Shuts off the cold or hot supply to the whole house.
3. Stopcock — The main water shutoff, typically under the kitchen sink or in a utility cupboard. Turning this off stops all water to the property.

Once you’ve turned off the supply, open the tap fully to drain any remaining water in the pipe. Have a towel underneath — there’ll be more water than you expect.

Important: If your isolation valves are seized (common in older houses), don’t force them. Use the stopcock instead and make a note to replace the isolation valves when you’ve finished — it’ll save grief next time.

Step 2 — Disassemble the Tap

The exact process varies by tap, but the general approach is the same:

1. Remove the handle. Look for a small cap on top of the handle (usually marked hot or cold). Prise it off with a flat screwdriver to reveal a screw underneath. Remove the screw and lift off the handle. Some modern taps use a grub screw on the side — you’ll need an Allen key for these.
2. Remove the headgear or cartridge housing. With the handle off, you’ll see a brass nut or housing. Use your adjustable spanner to unscrew it anticlockwise. Wrap the spanner jaws with tape or a cloth if the fitting is chrome — it scratches easily.
3. Pull out the internal mechanism. For compression taps, this is the headgear with the washer on the bottom. For ceramic disc and cartridge taps, the whole cartridge lifts out.

Take a photo at each stage. Seriously. When you’ve got six parts laid out on the worktop and can’t remember which order they came off, that photo is worth its weight in gold.

Step 3 — Identify the Worn Part

Now you can see what’s causing the leak:

Compression taps: Look at the rubber washer at the bottom of the headgear. If it’s flat, cracked, or crumbling, that’s your culprit. The washer is usually 12mm or 15mm — take it to the hardware shop to match the size if you’re unsure.

Ceramic disc taps: Inspect the ceramic discs for chips, cracks, or scoring. Even hairline damage will cause a leak. Also check the rubber seals around the cartridge.

Ball taps: The springs and rubber seats inside the valve body wear out. You can buy a complete ball tap repair kit that includes all the replaceable parts.

Cartridge taps: Check the O-rings on the outside of the cartridge. If they’re intact, the cartridge itself has probably failed internally — replace the whole unit.

Pro tip: If you’re heading to the hardware shop for parts, take the old ones with you. Sizes vary between manufacturers, and eyeballing it rarely works. Better yet, note the tap brand and model — most stock exact replacements.

Step 4 — Replace the Washer, O-Ring, or Cartridge

For compression taps (washer replacement):

1. The old washer is held on with a small nut or is simply pushed onto a spigot. Remove it.
2. If there’s limescale buildup on the seat, give it a clean with white vinegar and a toothbrush.
3. Press the new washer into place. Make sure it sits flat.
4. While you’re in there, check the O-ring on the body of the headgear. If it’s perished, swap it too — they cost pennies and prevent leaks from around the base of the tap.

For ceramic disc taps:

1. If only the rubber seals have failed, replace them. Soak new seals in warm water for a few minutes before fitting — they’ll be more pliable.
2. If the ceramic discs are damaged, replace the entire cartridge. Make sure you get the correct one — hot and cold cartridges are often different.

For ball and cartridge taps:

1. For ball taps, replace the springs, seats, and O-rings using a repair kit.
2. For cartridge taps, pull out the old cartridge and push in the new one. Align it correctly — there’s usually a tab or notch that matches a groove in the body.

Step 5 — Reassemble and Test

1. Reverse the disassembly — this is where your photos come in handy.
2. Wrap any threaded connections with a couple of turns of PTFE tape. Wrap clockwise (so it doesn’t unravel when you tighten).
3. Tighten the headgear nut firmly but don’t go mad — overtightening can crack the tap body or damage threads.
4. Refit the handle and the decorative cap.
5. Slowly turn the water supply back on. Turn it on gradually — slamming the valve open can cause a water hammer that shakes the pipes.
6. Open the tap and let it run for 30 seconds. Check for leaks around the base, at the spout, and at the connections underneath.

If it’s dry everywhere — congratulations, you’ve just saved yourself a plumber’s callout fee.

What If It Still Leaks?

If you’ve replaced the obvious parts and it’s still dripping, the issue is likely one of these:

• Damaged valve seat — the brass surface inside the tap body that the washer presses against can become pitted or corroded. You can resurface it with a valve seat grinder (around £10), or if it’s badly damaged, the whole tap may need replacing.
• Wrong size parts — even a slightly wrong washer or cartridge won’t seal properly. Double-check you’ve got the exact match.
• Cracked tap body — rare, but it happens in older taps. If the body itself is cracked, no amount of new washers will fix it. Time for a new tap.
• High water pressure — if your mains pressure is very high, it can force water past seals that would otherwise be fine. A pressure reducing valve on the incoming supply might be needed — that one is worth calling a plumber for.

Know your limits: If you’ve had a good go and it’s still leaking, there’s no shame in calling a plumber. You’ll be able to tell them exactly what you’ve tried, which saves them diagnostic time and might even save you money on the callout.

Recommended Tap Repair Kits

Having the right parts on hand makes all the difference. Here’s what I’d keep in the cupboard for tap emergencies:

Universal Washer Kit:

A box of assorted washers (typically 6mm to 25mm) costs a few pounds and covers virtually every compression tap in the house. Worth having even if you don’t need one right now — when a tap starts dripping at 11pm on a Sunday, the hardware shop isn’t open.

PTFE Tape:

Buy a multipack. You’ll use it on every plumbing job, and it’s one of those things that always seems to run out at the worst moment.

Ceramic Disc Cartridges:

If you’ve got quarter-turn taps, keep a pair of replacement cartridges. They’re specific to your tap brand and model, so check before you buy. Most UK taps use either a 45mm or 52mm cartridge.

O-Ring Kit:

A box of assorted O-rings is another cheap insurance policy. They perish over time, especially in hot water taps, and having the right size to hand saves a trip to the shop mid-job.

Adjustable Spanner:

If you don’t already own one, a 200mm adjustable spanner handles most tap nuts. A 250mm is handy for larger fittings. Spend a little extra on a good quality one — cheap spanners round off nuts and slip, which is how you scratch chrome fittings and bark your knuckles.

Fixing a leaking tap is one of those jobs that feels intimidating until you’ve done it once. After that, you’ll wonder why you ever considered calling a plumber for it. The total cost is usually under a tenner, the tools are basic, and the satisfaction of silencing that maddening drip is genuinely brilliant.