How to Fix a Dripping Tap: Step-by-Step Beginner Guide

26 July 2024

A dripping tap is one of the most common household annoyances, and left alone, it can waste a surprising amount of water over time. The good news is that most drips are caused by a worn washer or seal, which means you can usually fix the problem yourself in under an hour. This beginner-friendly guide walks you through the process step by step, with no plumbing experience required.

Before You Start: Gather Your Tools

You don't need a professional toolkit for this job. Most of these items are probably already in your home:

An adjustable spanner or wrench
A flathead and a Phillips screwdriver
A replacement washer or cartridge (take the old one to a hardware store to match it)
Plumber's tape (also called PTFE or thread seal tape)
A cloth or towel to protect surfaces and catch stray water
A bowl or bucket for small parts

Step One: Turn Off the Water Supply

This is the most important step, so don't skip it. Look under the sink for the isolation valve on the pipe feeding the tap and turn it clockwise until it stops. If there's no isolation valve, you'll need to shut off the main supply, usually found where the water enters your home. Once the water is off, open the tap to release any remaining pressure and let leftover water drain out. Plug the sink drain with a cloth so no small parts can fall down it — a classic beginner mistake.

Step Two: Dismantle the Tap

How you open the tap depends on its type. Most mixer taps have a small cap on top of the handle marked with hot and cold indicators. Pry it off gently with a flathead screwdriver, then unscrew the retaining screw underneath and lift the handle away. Beneath the handle you'll find a nut holding the cartridge or valve in place. Use your adjustable spanner to loosen it, turning carefully so you don't scratch the chrome finish. Keep the parts in the order you removed them — laying them out in a line on a towel makes reassembly much easier.

Compression Taps Versus Cartridge Taps

Older compression-style taps use a rubber washer at the base of the spindle, and a dripping issue here almost always means the washer has hardened or split. Simply unscrew the valve, pop out the old washer, and press in the new one. Modern cartridge taps, by contrast, contain a single ceramic cartridge; if one of these fails, you usually replace the whole cartridge rather than any individual part. If you're unsure which type you have, removing the handle and inspecting the mechanism will make it obvious.

Step Three: Replace the Faulty Part

Take the old washer or cartridge to a hardware shop and ask for an exact match — sizes and shapes vary more than people expect. Before fitting the new part, check the valve seat (the surface the washer presses against) for limescale or rough spots. Wipe it clean with a cloth; if it's badly scored, a valve seat grinder or reseating tool can smooth it out, though this is optional for a first attempt. Fit the new washer or cartridge, apply a little plumber's tape to any threaded connections you disturbed, and tighten everything firmly but not excessively — overtightening can crack ceramic parts or strip threads.

Step Four: Reassemble and Test

Put the tap back together in reverse order, following your parts lineup as a guide. Turn the water supply back on slowly, then open the tap and let it run for a few seconds to flush out any debris or trapped air. Check around the base and under the sink for leaks. If all is dry and the drip has stopped, congratulations — you've just completed your first plumbing repair.

Finally, a note on when to call a professional: if the tap keeps dripping after a fresh washer and cartridge, or if you notice water escaping from the body of the tap itself, the problem may be a cracked casting or a corroded valve seat that's beyond a simple fix. There's no shame in handing over to a plumber at that point — you've still saved yourself the call-out fee for the easy diagnosis.