Dripping tap: Fix a leaking tap or dripping mixer tap

A dripping tap is usually due to the washer or cartridge no longer forming a watertight seal. It’s hard to imagine a more common plumbing problem. The side effects range from a mild annoyance to a significant impact on your water bill. Even if you’re not on a meter, it’s still a waste of a precious resource. Plus, if left unchecked for a while, it can result in serious structural damage to a property. In this article, we’ll explain how it’s possible to fix a dripping tap, including a dripping monobloc tap.

What you’ll need

Before you start this task, you will need the following tools:

  • The replacement tap washer or cartridge
  • An adjustable spanner
  • Flat-edge and cross-head (Philips headed) screwdrivers

How to repair a dripping tap

1. Isolate the tap

The first thing to do is to shut off the water to the tap in question. You can do this by closing the isolation valve on the pipe. Using the flat-edge screwdriver, simply turn the screw on the valve a quarter-turn. With the slot for the screwdriver no longer in line with the pipe, the valve should be closed.

Once you have isolated the tap, open it to release any water still in the pipe.

If it’s a hot dripping tap

  • If you have a combi boiler, turn off the mains stopcock. This is usually under or near the kitchen sink. This will shut off the water to every outlet in the home.
  • If you have a hot water cylinder, turn off the gate valve on the cold supply pipe. This is easily identified as the red, wheel-shaped valve on a pipe running down to the base of the cylinder.

For a cold dripping tap

  • If it’s the kitchen cold tap dripping, turn off the mains.
  • If it’s a bathroom cold tap and you have a cold water storage cistern in the loft, you may need to isolate the supply from the cistern. Close the gate valve on the supply pipe; you’ll normally find this on the supply pipe in loft close to the cistern. If there isn’t a gate valve, you will need to isolate the supply to the cistern and drain it down. Click here to learn how to do this.

2. Locate and remove the screw

Put the plug in the sink to stop any screws and parts from going down the drain. Then, locate the little screw which holds the tap together. You’ll normally find this underneath a decorative ‘H’ or ‘C’ cap. Pry it off with the screwdriver and unscrew the screw.

For monobloc taps with a single lever, the screw is usually located behind the hot/cold marker. Pry it off with the screwdriver to reveal a small grub screw. If this cannot be unscrewed with a screwdriver, you may need an Allen key.

Once you’ve removed this screw and the tap handle, you may also need to remove any other metal shroud which covers the inside of the tap.

3. Remove the tap headgear or cartridge

You’ll now see the top of the brass assembly which holds the washer. This is known as the headgear or cartridge. Undo the nut with an adjustable spanner. If it’s tight, protect the tap with a cloth or towel should you lose your grip.

You should also hold onto the body of the tap to prevent any force from twisting the whole thing in its place, as this may loosen it from its fitting or twist the pipework below it.

4. Replace the washer

Now the moment of truth for repairing a dripping tap – swap the faulty washer for a new one. To be sure of getting the right one, you can bring the headgear or cartridge to your local plumbers merchant.

You may find that the washer is held in its jumper via a small retaining nut or screw. You’ll need to remove this you can replace it.

Once you’ve replaced the washer, simply reassemble the tap by following these instructions in reverse. Restore the water supply by re-opening the mains or the adjacent isolation valve. Congratulations – your dripping tap should be no more!