The majority of dripping taps can be solved by simply replacing the washer (see Replacing the washer in a tap or Replacing the washer in a reverse-pressure tap). This should be done promptly to avoid unsightly stains on sinks/baths because the problem will get worse and the seating of the taps will require replacement.
If the leak is occurring from around the spindle of the tap or the tap is juddering during use then this can often be resolved by replacing the gland packing or O-ring seals in the tap. See Replacing O-rings and Gland packing.
If a tap continues to drip once the washer has been replaced then it will probably require reseating. Reseating is required because grit or general wear and tear, has caused the seating to become worn, this can be remedied by reseating the tap. See Reseating a tap.
Some older taps which are brass, may suffer from old age by developing cavities and becoming porous. If this is the case then the taps will require changing. See Fitting new taps for more details.
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