Toilet Repairs: Toilet Leaking at Base, Cistern Leaks and Overflows

A toilet leaking at the base, a cistern that drips or runs constantly, or a toilet overflowing onto the floor are repair jobs rather than drain jobs, and they sit within our general plumbing work. We find which seal, connector or valve has failed, fix it, and check the pan and cistern are watertight before we leave. If the toilet is blocked rather than broken, see blocked toilet unblocking. Call 07427 195142.

Toilet leaking at the base

Water around the foot of the pan has three common sources, and the fix depends on which one it is. Dry the floor and watch after a flush.

• Water appears straight after flushing: the pan connector or seal between the toilet outlet and the soil pipe is leaking
• Water is there even without flushing: the supply connector, the isolating valve or the cistern bolts are weeping and running down
• A pool that smells: waste water is escaping, which needs dealing with promptly for hygiene and to protect the floor

Cistern leaking

Cisterns leak in two ways. Externally, water drips from the underside where the cistern sits on the pan, usually because the doughnut washer or the fixing bolt washers have perished. Internally, water trickles constantly into the pan because the flush valve seal no longer closes, which wastes water and can be heard as a faint hiss. Both are repaired by replacing the worn part rather than the whole toilet.

Toilet overflowing

If the cistern overfills and water comes out of the overflow pipe, the fill valve is not shutting off. If the bowl itself rises to the rim when you flush, the water has nowhere to go, which means a blockage in the pan, the soil pipe or the drain beyond. The first is a repair; the second is unblocking. Do not keep flushing a bowl that is rising.

Where a toilet is both blocked and leaking, the blockage often caused the leak by forcing water back through the pan seal. We clear the obstruction first, then reseal or replace the connector so the repair lasts.

Blocked urinals

Urinals in pubs, offices and workplaces block with scale, paper and items dropped into the bowl. The trap and waste behind them need clearing and flushing through, and where several urinals share a waste, the fault may sit further along the branch. For businesses with washrooms used by the public, see also commercial drain unblocking.

What a toilet repair involves

We isolate the water, empty the cistern and inspect the parts that are failing. Washers, seals, fill valves, flush valves and pan connectors are replaced as needed. Where the pan has to come off to reach the connector, we lift it, fit the new seal, and refit and reseal it to the floor. Then we flush repeatedly and check for drips around every joint we have worked on.

Landlords and letting agents often book toilet repairs alongside other small plumbing jobs as part of a maintenance visit, which saves arranging access more than once.

When the leak is not the toilet

Occasionally water by the toilet comes from somewhere else: a leaking waste from a nearby basin, condensation on a cold cistern in winter, or a soil pipe joint behind the boxing. If the toilet checks out dry, we look at what else is close by. Problems with the vertical soil pipe itself are covered on our soil stack unblocking page.

Questions