My Toilet Rocks When I Sit On It

Tap, thump…tap, thump…you hear the noise from your bathroom. It’s rocking like a baby being comforted by its mother: short, gentle movement; not so much that you feel it, but enough to make a noise.

Maybe you’ve been there before. You go in the bathroom, inspect, and confirm that your toilet is moving side-to-side. If the toilet shakes as you sit on it, there are some simple solutions. You can also call a plumber or handyman if the problem is too complicated for you to handle.

Causes of a Rocking Toilet

The rocking toilet is usually a sign of a problem with the solid waste line. This can be caused by clogging, blockage, or even a defective valve. There are also cases when the water supply has been shut off in the building, and the toilet bowl is empty.

There are several possible causes for a rocking toilet:

Toilet Bowl with very little water

Clogging: The most common cause of rocking toilets is clogging. If your toilet bowl is not filled with water, it will rock back and forth because of gravity. In most cases, this happens when there is too much paper or other solid waste materials in the bowl. However, there are times when even if you have just flushed your toilet, it still rocks back and forth because of clogging near the drain line.

Blockage: Another possibility is a blockage somewhere in your plumbing system that prevents water from flowing freely through it. This may be caused by various factors, including tree roots growing within your pipes or foreign items, such as toys, being lodged inside them when placed in your house. If this happens to be the case, you may need to call an expert plumber who knows how to handle these situations effectively without causing any damage to other parts of your house.

defective flapper valve

Defective flapper valve: The flapper valve is a rubber stopper at the bottom of your toilet tank that opens when you flush and closes when the water level drops below it. You can test this by trying to flush your toilet without putting anything down the drain first. If there’s still water in your tank and it doesn’t flush, you have a defective flapper valve.

Broken flange: A broken flange is one of the most common causes of rocking toilets. The flange is the metal ring that connects your toilet to the floor and supports the bowl’s weight. If the flange breaks or becomes loose, it will cause the toilet to rock back and forth when you flush.

Loose bolts in the tank or bowl: The bolts that hold the tank to the bowl may be loose or missing entirely. You can check for this by removing the lid from your tank and looking for any gaps between the tank and bowl or by opening up your toilet bowl at home (or, if you’re brave enough, using pliers). If there’s a gap, apply some epoxy glue or cement to fill it up, and flush it with both surfaces. Once everything is glued together, put everything back together and test if everything works properly before reinstalling it in your bathroom.

Wobbling floorboards: If your floorboards are wobbly or uneven, this could also cause rocking toilets! One way to fix this problem is by adding shims under your floorboards to create a level surface for your toilet. Another solution would be to install wood floors in place of old linoleum or tiles to be more sturdy than before!

How to Fix a Rocking Toilet

The rocking toilet is an annoying problem that you can quickly repair. If your toilet rocks back and forth, the most likely cause is an improperly installed wax ring or flange. A rocking toilet can also be caused by a cracked or broken floor flange or a loose bolt in the toilet’s base.

First, you will need to determine why your toilet rocks to fix the problem. Then, you can make the necessary repairs to fix your rocking toilet.

How to Fix a Rocking Toilet (Step by Step)

Remove the Tank Cover

Open up the tank cover and find where it connects to the water supply line with a valve. Unscrew this connection to obliterate the tank cover from its place. Set aside this piece of equipment for now; you will need it again later in this process.

toilet tank bolts keep the the bowl and the tank together
Image from Joe Tominsky Jr

Remove Tank Bolts

Use pliers to remove all four bolts underneath your tank and any other bolts holding down parts of your tank, such as handles, overflow tubes, and drain valves, if they are not already removed before using the toilet.

Disconnect Flapper Valve & Arm Assembly

Using pliers, disconnect the plastic flapper valve from its arm assembly. The arm assembly is connected to the tank’s float ball by a chain, which will probably be rusted if you’ve had problems with your rocking toilet before.

handman removing the toilet tank from toilet

Lift the Tank

After removing all of the fasteners, raise the tank approximately an inch over the basin. Wipe away any debris accumulated on or around the flange (the metal ring that sits on top of the floor) using a sponge or towel. This region must be spotless for fresh wax rings to perform well.

Clean Out Drain Hole

The hole in your toilet’s drain line should be cleaned out with hot water and some bleach or another disinfectant agent if there is any buildup from past clogs or use. This will help ensure that no debris will get trapped under your new wax ring while being installed later in this step-by-step guide.

a man removing wax ring and cast iron toilet flange
Image from Plumbaholics LLC

Remove Old Wax Ring

If your toilet is rocking because of a bad wax ring, you’ll need to remove it and replace it with a new one. To do so:

  1. Use pliers to pull off any remaining pieces of wax from around the base of your toilet bowl.
  2. Use another pair of pliers to grab onto one side of the old wax ring and pull it out from under your toilet bowl (this is usually easier than getting around both sides at once).
  3. Place it in a safe place for later use if possible.

Install New Wax Ring and Gasket

Clean all wax and debris from around the base of the bowl. Then install a new wax ring with a gasket in place. The gasket should sit flat against the floor of the toilet bowl. The bolt holes in the base of your toilet should line up with those on your floor. If they don’t, you can use an Allen wrench or Phillips screwdriver to move them into position by turning them counterclockwise until they line up correctly. The bolts should go through both rings and be tightened securely with pliers or a wrench.

toilet tank bolts and gasket replaced
Image from Smithys Plumbing

Install Tank Bolts

Install tank bolts back into place once everything has been properly installed according to manufacturer specifications and tighten them down evenly. But not excessively tight as this may cause cracking or damage to the tank itself, which will require replacement of parts or the entire unit altogether depending on the severity of damage caused by over-tightening bolts during the installation process.


The most important thing to remember when fixing a rocking toilet is that it’s easy to break things without realizing it. Don’t try to over-tighten hinges or jiggle bolts too much. If you’re confident in your ability to replace toilet parts correctly, you should be able to repair your rocking toilet issue with minimal fuss.

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