Fixing a Dripping Tap Without Calling a Plumber

Why a Dripping Tap Is Worth Fixing Today

A tap that drips once a second wastes somewhere between 15 and 20 litres of water a day. Over a year that is roughly 5,500 to 7,000 litres — enough to fill a small water butt many times over, or run around 70 baths. If it's the hot tap, you are paying twice: once for the water, and again for the gas or electricity used to heat it. A new washer costs pennies and a cartridge is usually under £20, while a plumber's call-out for the same job often starts at £60 before any parts are added. This is one of the few household repairs where the DIY route wins on every measure.

Before You Start: The Essentials

Water off first, always. Everything else is straightforward once the supply is isolated.

• Close the isolating valves on the hot and cold pipework under the sink if you have them. If not, turn off the main stopcock — often under the kitchen sink, in an airing cupboard, or outside near the boundary.
• Open the tap fully to drain the pipe, then close it again.
• Gather an adjustable spanner, cross-head and flat-head screwdrivers, a cloth, a small bowl and a torch.
• Buy a mixed pack of tap washers, or take the old part to a hardware shop for a match.
• Put the plug in or place the bowl over the plughole. Tiny screws and circlips love to vanish down there.

Take a photo at each stage on your phone. Reassembling a tap is far easier when you can see exactly how it looked beforehand.

Traditional Taps: Replacing the Washer

Older pillar taps — the ones with a crosshead or a small lever on top — rely on a rubber washer pressing down onto a metal seat.

• Prise off the index cap on top of the handle (the little disc marked hot or cold) with a flat-head screwdriver or a fingernail.
• Undo the screw underneath and lift the handle off the splined spindle.
• Wrap the chrome in a cloth, then use the spanner to undo the headgear nut, sometimes called the bonnet, and lift the whole assembly out.
• At the bottom you'll find the jumper with its worn washer held by a small nut. Undo it and fit a new washer of the same size. Half-inch and 3/8 inch are the common ones, with 3/4 inch on larger bath taps.
• Check the metal seat inside the tap body for grooves. If it feels rough, a reseating tool will grind it smooth. If the damage is deep, replace the tap body instead.

A smear of silicone plumber's grease on the threads makes everything easier to undo next time. Don't overtighten the bonnet — hand tight plus a quarter turn is plenty, or you'll split the washer you've just fitted.

Modern Taps: Swapping a Ceramic Cartridge

Quarter-turn and single-lever mixer taps have no washer at all. They use a ceramic cartridge, and when the discs inside become scored by grit or limescale, the tap drips.

• Isolate and drain the supply as before.
• Remove the handle. Many models have a small grub screw at the back or hidden under a cap; on others the lever simply unscrews.
• Undo the retaining nut or circlip holding the cartridge, then lift it out.
• Note which way round it sits — the flat or notched edge usually faces a particular direction.
• Measure the diameter across the base (35mm and 40mm are the usual sizes) and count the splines if it's a splined fit. Buy a like-for-like replacement.
• Fit the new cartridge, grease the O-rings lightly, and reassemble in reverse.

In a hard water area, cleaning the cartridge in vinegar now and then, or fitting a scale reducer, will buy you several extra years of trouble-free use.

When the Drip Isn't the Cartridge

Not every drip comes from the valve mechanism, so it pays to look at where the water actually appears before you buy parts.

• Water at the base of a swivel spout: the spout O-rings have perished. A cheap kit usually sorts this.
• Water around the base of the tap where it meets the sink: the back nut underneath has worked loose. Clean off the old sealant and reseat the tap.
• A tap that drips only when the system is hot: thermal expansion is pushing past worn seals. A cartridge or washer change is still the answer.
• A seized stopcock or a tap you cannot free: stop here. Forcing a stuck valve can flood the kitchen, and that really is a job for a plumber.

If you have isolated the supply and cannot shift the headgear or the cartridge, a plumber's visit is money well spent. The trick is knowing the difference between a job that needs a spanner and a job that needs a professional.

Turning the Water Back On and Testing

Open the isolating valve slowly, let the pipe fill, then open it fully. Run the tap for a few seconds, close it, and watch for a full minute. Dry the tap with a cloth so any fresh weep shows up clearly, and check under the sink for damp around the connections. If it still drips, the usual culprits are a washer seated crooked, a cartridge of the wrong size, or debris trapped on the seat. Take it apart once more, rinse the parts and refit.

Keep a spare washer or cartridge in the cupboard alongside your other odds and ends. A repair that takes five minutes is far easier to face when the part is already to hand, and you'll never again stand listening to that drip wondering whether it's worth a phone call.