Toilet Rocking Or Leaking At The Base

What's happening?

A pan that rocks has either lost its fixings or was never fixed properly, and the movement is what causes the leak rather than the other way round. Every flush pushes the pan against the soil connector; if the pan can move, the connector flexes and eventually leaks at the spigot, dribbling clean flush water and some waste onto the floor where the two meet. Water pooling at the base can also be condensation off a cold cistern in a warm room, or a leak from the cistern-to-pan doughnut washer running down the back of the pan, so the first job is to work out where it actually starts. Fitting matters here: a wall-hung pan on a frame that is not solidly anchored will move the same way, and a close-coupled pan bedded on a bathroom floor that itself flexes will loosen again however tight the screws go.

What usually causes it?

• Floor fixings missing, loose, or screwed into tiles or chipboard with nothing solid behind them
• A pan bedded with silicone alone, which does not hold it against the rocking load of someone sitting down
• An uneven or unlevel floor under the pan foot, so it seats on two points and rocks
• A rigid or badly cut soil connector that has cracked or slipped off the pan spigot
• A perished doughnut washer between cistern and pan, leaking down the back and appearing at the base
• Condensation on a cold cistern and pan in a warm, humid room, dripping to the floor
• A wall-hung frame not properly anchored to the structure, letting the whole pan flex

When should you call a bathroom fitter?

Call a bathroom fitter if the pan still rocks once the fixings are tight, if the floor under it is soft, if the soil connector is cracked, or if you have a wall-hung pan that moves at all. A moving wall-hung pan means the frame or its anchors, which is behind the tiling. Call sooner if there is a stain on a ceiling below or the smell of drains in the room, since that means the connector is passing.

What will the bathroom fitter actually do?

• Establish the source by isolating each possibility — floor fixings, soil connector, cistern washer, condensation
• Lift the pan where necessary and check the floor beneath it for rot, movement and level
• Repair or re-deck a soft or uneven floor so the pan seats fully on a solid, level base
• Refix the pan with the correct fixings into sound structure, packing rather than forcing it level
• Renew the soil connector and the cistern-to-pan washer, and check the flush and the fill valve for compliance
• Test with repeated flushes, then seal the pan to the floor leaving the rear open so any future leak shows

Working out where the water starts

1. Dry the pan, the cistern and the floor completely and leave the room unused for an hour.
2. Water back with nothing used means condensation on cold ceramic in a humid room.
3. Sit on the pan without flushing; water now means the floor seal or the connector is moving.
4. Flush and watch the base and the back of the pan; water only now means the connector or the doughnut washer.
5. Dry the back of the pan and feel along the cistern joint to separate the two.