Running, Weak-Flushing or Leaking Toilet: Fix Guide
The three toilet failures behind 90% of callouts, and which ones are genuinely DIY.
The endless run
A toilet that runs constantly is losing water over the overflow or past the flush seal. Lift the lid: water climbing towards the overflow tube means the fill valve; water level fine but running anyway means the flapper or drop valve seal. Both parts cost pounds and fit without tools beyond a spanner.
The weak flush
Check the rim jets for scale (a mirror helps), the water level against the marked line, and the flapper opening fully. In hard-water areas the jets scale shut over years, descaling transforms a flush more often than any new part.
Water at the base
A puddle at the base after flushing is the one to take seriously: usually the pan-to-soil seal, occasionally a cracked pan. Rocking the pan even slightly makes it worse. This one is worth a professional, because the failure mode of a DIY reseal is sewage under the floor.