Quick answer
A tap that drips after being turned off often has a worn washer, cartridge or ceramic disc. Isolate its water supply before dismantling it; if you cannot identify the correct isolation valve or the tap continues leaking, call a plumber.
Identify the tap and prepare
A slow drip wastes water and can mark a basin or sink. The repair depends on the tap design. Traditional taps often use a rubber washer, while many modern mixer taps use a replaceable cartridge or ceramic discs. A drip from the spout differs from a leak around the handle or beneath the sink; note where water appears before starting.
Gather a cloth, suitable screwdriver and the replacement part only after identifying the tap. Keep small components in order. Do not force a stuck handle or use a tool that may damage its finish. If the tap is part of a complicated mixer or has no accessible isolation valves, a plumber can identify the arrangement.
Isolate water and make the repair
- 1Turn off the isolation valves on the hot and cold feeds beneath the basin or sink, using a flat screwdriver if required. If there are no valves, use the household stopcock. Open the tap to release pressure and confirm the flow stops.
- 2Plug the waste so screws cannot fall into it. Remove the handle carefully, then lift off the cover or retaining nut as the design allows. Take a photo of each stage to help with reassembly.
- 3Inspect the washer or cartridge for wear, cracks or scale. Take the old part to a plumbing supplier to match its size and type. Replace it without forcing components; clean accessible seating surfaces gently.
- 4Reassemble the tap, open the isolation valves slowly and check the tap and pipe connections for leaks. Test both hot and cold operation.
When a simple repair is not enough
A tap may continue to drip if its valve seat is damaged, the replacement component is incorrect, or debris has entered the mechanism. A leak at the base or under the sink may instead come from a loose connection, failed seal or supply hose. Do not overtighten fittings: excessive force can damage threads or seals.
If the tap is very old, badly corroded or difficult to isolate, replacement may be more sensible than repeated repairs. TraceFix Plumbing engineers in Birmingham and London can diagnose leaking taps and related pipework.
When to call a plumber
- You cannot safely isolate the tap or the stopcock will not turn.
- Water continues to leak after the tap is reassembled.
- There is a leak beneath the sink, from a pipe joint or inside a wall.
- The tap or pipework is corroded, loose or damaged.