How to Stop a Dripping Tap (and When to Call a Plumber) in Chelsea

A dripping tap almost always means one small internal part has failed, and replacing it stops the drip for good. On older taps the culprit is usually a perished rubber washer or O-ring; on newer taps it is a worn ceramic disc cartridge. Fixing it early is worth the effort because a steady drip wastes water and money. A single tap dripping once a second can lose more than 15 litres a day, which adds up to over 5,000 litres a year, and on a hot tap it wastes the energy used to heat that water too.

Taps drip for a handful of common reasons, and knowing which applies tells you what to buy. A worn or hardened washer stops sealing against the valve seat, so water weeps from the spout. A perished O-ring lets water escape around the base or handle rather than the spout. A damaged or scored ceramic cartridge, the sealing part in most taps made in the last twenty years, fails to close fully. A corroded or pitted valve seat, the metal ring the washer presses onto, chews up new washers so the drip returns within weeks. And in Chelsea especially, limescale from London's hard water builds up on seats and cartridges and holds them slightly open.

London sits in a hard-water area, and Chelsea taps take the brunt of it. Scale forms a crusty white deposit on the working parts, wears washers faster and stiffens cartridges, which is why taps here often need attention sooner than in soft-water regions. If your taps fur up quickly, or a new washer only lasts a short time, scale is likely part of the problem, and our advice on managing hard water and limescale in Chelsea homes is worth reading alongside this guide.

Before touching anything, isolate the water to that tap. The quickest route is the small isolation valve on the supply pipe directly beneath the basin or sink: turn the slot on it a quarter turn with a flat screwdriver so the slot sits across the pipe, which is the off position. There are usually two, one for hot and one for cold, so close whichever feeds the dripping side, or both if you are unsure. If there is no isolation valve, turn off the main stopcock, usually under the kitchen sink, in a utility cupboard or near the entrance in many Chelsea flats and mansion blocks. On a tap fed from a cold-water storage tank you may also need to isolate or drain that supply. Then open the tap fully to drain the standing water and confirm the flow has actually stopped before you go further. Put the plug in so no small screws disappear down the waste, and lay the parts out in order as you remove them.

Next, identify your tap type, because it decides the repair and the part you buy. A traditional tap has a handle you turn several times to open or close, and inside it uses a rising spindle and a rubber washer at the bottom of the valve. A ceramic-disc tap opens with a short quarter turn or half turn of the handle and uses a cartridge holding two polished ceramic discs that slide across each other. A mixer or monobloc tap has a single body feeding one spout, sometimes with two heads and sometimes with one lever, and almost always uses cartridges rather than washers, often a matched hot and cold pair. A quick test: if the handle turns a long way and gets stiffer as it closes, it is likely washer-based; if it snaps open and shut with a light flick, it is ceramic. Note the brand stamped on the tap or spout, because it helps a merchant match the internals.

To replace a washer on a traditional tap, first prise off the decorative cap on top of the handle to reach the retaining screw, undo it and lift the handle away. Unscrew the headgear nut with an adjustable spanner to expose the valve. Hold the tap body steady so you do not twist the pipework. At the bottom of the valve you will find the washer, held by a small nut or a push fit. Remove the old washer, take it to a merchant to match the size exactly, fit the new one, and reassemble in reverse. While it is apart, check the O-rings on the spindle and replace them too if they look flattened or perished.

To replace a ceramic cartridge on a modern or mixer tap, remove the handle in the same way, then unscrew or unclip the retaining collar to lift the cartridge out. Cartridges are not universal, so match the old one precisely on diameter, height, spline count and whether it is a hot or cold side, or take a clear photo and the old part to the merchant. Seat the new cartridge the same way round, tighten by hand plus a gentle turn with a spanner, and refit the handle. Restore the water slowly, then run the tap and check for drips at the spout and around the base before you call it done. A drip from the spout means the cartridge or washer is not sealing; weeping from the base usually means an O-ring rather than the main seal.

Whichever repair you did, deal with limescale while the tap is open. Wipe scale off the valve seat and cartridge housing, and if the seat feels rough run a fingertip round it: a pitted or corroded seat will shred a fresh washer, so it needs re-cutting with a seat grinding tool or the tap replacing. A light descale of removable parts in a proper descaler helps, but never use harsh acid on plated finishes. If a new washer or cartridge drips again within days, the seat, not the washer, is usually the real fault.

Call a plumber when the job stops being a simple swap. Seized handles, corroded headgear nuts that will not move, or fittings so scaled they risk snapping the pipe are all reasons to stop before you cause a leak. A pitted valve seat that needs re-cutting, or a tap that still drips after a correct cartridge change, points to wear beyond a quick fix. And high-end, antique or imported taps common in Chelsea bathrooms often use manufacturer-specific cartridges and ceramic sets that must be ordered to the exact model, where forcing a near-match part damages the tap. If you cannot isolate the water, or turning the stopcock reveals it is seized, treat that as the priority and call for help.

For a dripping tap that has become a bigger job, or a tap you would simply rather have sorted properly first time, Emergency Plumber Chelsea handles leaking tap repair as part of our everyday minor plumbing work across SW3 and SW10. We carry common washers, O-rings and cartridges, can re-cut a worn seat or replace the tap where repair is not worth it, and quote before any major work so you know the cost. Tap and valve replacement typically starts from around £90 as a guide, with the final price confirmed on site. Call 020 3002 6667 and describe the tap and where it drips so we arrive with the right parts.

Quick tips

• Fit the plug before you start so dropped screws and washers do not vanish down the waste.
• Take the old washer or cartridge to the merchant, or a clear photo with measurements, so the replacement matches exactly.
• If a fresh washer drips again within days, suspect a corroded valve seat rather than the washer itself.
• In hard-water Chelsea, descale removable tap parts gently, but never use strong acid cleaners on plated or antique finishes.
• Do not force a seized handle or headgear nut; a snapped fitting turns a small drip into a real leak.

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