Wobbly Toilet That Rocks When You Sit Down

A rocking toilet feels like a minor irritation, and it is, right up until the pan connector gives up and waste water starts running under the floor. Ceramic does not bend, so every movement is taken by the fixings, the seal at the back and the joint between the pan and the cistern. The repair is well within reach of a careful DIYer, but only if you fix the underlying reason rather than pulling the screws down harder, which is how most cracked pans happen.

Work out where the movement is

Sit on the toilet and get someone to watch the base, then the cistern, then the wall behind. Movement at the base means fixings or an uneven floor. Movement of just the cistern means the cistern to pan bolts or the wall bracket. If the whole assembly shifts and the floor gives slightly with it, the floor itself is the problem and no amount of tightening will help.

Cause one, an uneven floor

Most rocking pans are simply bridging a hollow. Older houses around Stoke often have several generations of floor covering, and when a new floor goes down the pan ends up sitting on three points instead of a flat bed. The correct fix is to lift the pan, check where it bears with a straight edge, and pack the low points with rigid plastic packers or bed the pan on a thin layer of flexible adhesive so it is fully supported before any fixing goes in.

Cause two, worn or wrong fixings

Screws into old, crumbly floorboards or into a chipboard floor that has been wet will spin and hold nothing. Fixings need to bite into sound timber, or into plugs set properly in a solid floor. Always use the rubber or nylon washers under the screw heads so metal never touches ceramic, and always tighten by hand, alternating sides, until snug and no further.

Cause three, the pan connector is fighting the pan

A stiff or badly angled pan connector pushes the toilet forward or sideways, and the pan then pivots on that push. If the toilet only sits flat when you hold it against the connector, the waste alignment is wrong and needs the right offset or flexible connector rather than being forced.

Cause four, a soft or failing floor

Chipboard that has been wet from a previous leak turns to a soft biscuit, and the fixings have nothing left to grip. This is common in bathrooms where a slow leak went unnoticed. The board has to be cut out and replaced. Screwing into it again is a waste of an afternoon.

A safe way to refit a pan

1. Turn the water off at the isolating valve and flush to empty the cistern, then sponge out the last of the water.
2. Disconnect the supply and undo the floor fixings. Ease the pan off the connector rather than twisting it.
3. Clean the floor, check it with a straight edge and deal with any soft board.
4. Dry fit the pan, pack any gaps until it sits solid without rocking, and check it is square to the wall.
5. Refit the connector, fix down hand tight with the correct washers, and reconnect the water.
6. Run a small bead of sanitary silicone around the front and sides of the base, leaving the back open.

When to get someone in

If the floor is soft, if the pan is cracked, if the waste alignment is wrong, or if you have a wall hung pan on a concealed frame, get a fitter. Concealed frames carry the whole weight of the user and must be fixed to something structural, and a frame that has worked loose is not a job to improvise.

Local help

We replace toilets, repair floors and fit cloakrooms and bathrooms across Stoke-on-Trent, Newcastle-under-Lyme and Stone. Use the enquiry form to describe the problem and we will come and look, free of charge, with a fixed written price within 24 hours.

Common questions