Find a Leaking Toilet Cistern — Cloakroom
A leaking toilet cistern in the cloakroom is usually a worn seal or compression olive — a £3 fix caught early. Left unchecked it damages flooring, joists and ceilings below. Here is the trade method.
Step-by-step method
1. Isolate the water
Nearest isolator or property stopcock. Prove zero pressure by opening the toilet cistern.
2. Dry and identify
Dry the toilet cistern completely. Run 30 seconds. The first bead of water shows the exact fault.
3. Strip and inspect
Remove cover/collar. Inspect washer, O-ring, olive. Take to Screwfix/merchant to match.
4. Refit with new seal
Grease O-rings with silicone (not vaseline). PTFE-tape 5 wraps clockwise. Hand-tight + 1/4 turn.
5. Pressure-test
Open isolators, purge, run 60 seconds. Re-check after 24 hours.
Frequently asked questions
DIY or plumber?+
Non-gas leaks are DIY-friendly. Plumber callout £70–£140.
Emergency?+
Weeping = 24h. Active spraying = same day.
Insurance?+
Sudden damage yes; gradual leaks no.