How to Fix a Wobbly Toilet?

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A wobbling toilet is a serious annoyance. It makes you feel strange and insecure in a place where comfort is the only thing you seek. No king likes a rocking throne, but fear not — we have a word of advice for you!

Several things can cause your toilet to rock back and forth, including a bumpy floor and a broken flange. Fortunately, each problem has an easy fix.

In this article, we’ll go through the most common reasons why your toilet rocks back and forth as well as how you can fix the issue.

What Makes the Toilet Wobble?

A floor-based bowl has an oval base with security bolts and a toilet flange.

The flange is the part that sits on top of the hole and the drain pipe on your floor. It has a rubber top, aka wax ring, and its purpose is to support and hold the toilet. 

When your toilet moves around, it does so for one of these reasons:

  • A bumpy floor can make the toilet shaky
  • When toilet bolts are loose, they allow the bowl to move around
  • A broken flange also stops the toilet from sitting properly

How to Fix a Wobbly Toilet?

The way you fix a rocking toilet depends on the problem causing it. Here are the steps that solve the first two issues – an uneven bathroom floor and loose toilet bolts.

Step 1: Tighten the Bolts

Step one is to check if the bolts are in place. If they are loose, tighten the bolts immediately. Use an adjustable wrench to screw the nuts holding the bolts. 

Turn them clockwise to secure the base of the toilet bowl, but don’t twist the wrench too hard because it might break the porcelain. When you seal the nuts, see if the toilet bowl is moving. 

If not, your problem is gone. If it still wobbles, go on to the next step.

Step 2: Search for Leaks

The second step is critical because leaks tell you whether the toilet flange is malfunctioning.

Check from underneath to see if there’s water coming from somewhere around the toilet. If you don’t see puddles around the toilet already, try putting a dry piece of cloth or toilet paper on the floor — don’t use your toilet for an hour or two. 

When you come back, check the condition of the toilet paper or the cloth. If the toilet is leaking, the floor flange is damaged. In that case, you can jump to the next chapter dealing with this problem. 

If there are no leaks, move on to the next step.

Step 3: Pinpoint the Gaps

Now it’s time to check your bathroom flooring and pinpoint the gaps between the toilet and the floor. These gaps make a rocking toilet move.

Start by observing if there’s any space around the bowl. Examine whether there’s enough of a gap to allow movement. When you notice a gap, push a bowl against it to check if it wobbles. 

Larger gaps allow the bowl to move, and they are the ones you need to get rid of. They make the toilet shaky and allow you to create steep angles while sitting on the throne and leaning from one side to another. 

Step 4: Set the Shims

When you identify the gaps, you can fill them with plastic shims. You’ll place a few shims under the bowl, with the thinner edge sliding under the toilet base. Push the shim until there’s no room left to fill — do the same with every shim and gap. 

Sometimes the gap is too thin for the shim to slide in, so you’ll need to lift the toilet slightly — it’s the only way to insert the shim. After that, you can sit on the bowl to test it. 

If the toilet bowl still wobbles, make sure that you’ve pushed the shims enough to fill the gaps without elevating the toilet. That’s the only way to maintain the balance.

Step 5: Cut the Shims

The shims you place beneath the toilet are too long, and you don’t want them to stick out. A wider part of the shim is easy to see even from distance, so there’s no reason to leave it like that.

Use a utility knife to cut the shims right to the surface of the bowl. Do your best to cut everything that sticks outside the toilet base – it will hide the shims and look like there’s nothing but the toilet bowl on the floor.

You can even save the remnants in the garage — perhaps you will use them to level a table or a cupboard sometime soon. 

Step 6: Apply Caulk to the Oval Base

You can now hide the shims with caulk. Caulk like Dap Alex Plus comes in a tube, so you need to squeeze it to apply the product. Caulk does two things:

  • It covers the shims and hides the signs of your work
  • It prevents water leakages

However, we encourage you not to apply caulk around the entire toilet base. This is important because caulk stops you from noticing the toilet is leaking at its base, so it’s better to leave a small section of the base uncovered. 

The side directly facing the wall is best since no one can see it, so you don’t have to hide the shims.

When you add caulk to the toilet base, let it dry before using the toilet. It takes an hour to dry fully. When the caulk dries, it will protect your toilet from wobbling together with the shims.

Your Toilet Still Wobbles? Replace the Toilet Flange

Sometimes the bowl moves back and forth because of the worn-out toilet flange. In this case, it will take you more time to repair the loose or rocking toilet.

Step 1: Close the Valve

You’ll need to shut the valve connecting your water supply to the toilet. The valve hides behind the toilet, but you can reach it easily. Twist the shut-off valve clockwise to close it and flush the toilet to empty the tank. 

You can also plunge the bowl to remove the remaining water. 

If you haven’t used the shutoff valve for a while, it may be hard to rotate. In this case, use a penetrating oil such as WD-40 to spray the valve and loosen it. After that, twisting the valve should not be an issue. 

Step 2: Remove the Bowl

Now it’s time to remove the rocking bowl.

There is a metal hose connecting the shutoff valve with the toilet tank — you must detach it using adjustable wrenches. The next task is to unscrew the bolts connecting the tank to the bowl. 

They are on the bottom of the tank, as well as the supply line directing water from the tank to the toilet bowl. Remove both parts by twisting the safety nuts counterclockwise. 

The next thing is to remove the bolts from the toilet base. Unscrew them with a wrench just like the tank bolts. Finally, you can pick the bowl and place it on the ground horizontally. 

That way, you can access the bottom of the bowl and replace the existing elements.

Step 3: Remove the Old Flange

Step three is about removing the old flange. It has a wax seal that sticks to the bowl, so use a putty knife for scratching it off the surface. Metal flange bolts keep the toilet flange fixed to the ground, so you have to remove them. 

Turn the flange bolts counterclockwise using a flathead screwdriver. After that, lift the old flange and throw it away. Remember to clean the bottom of the toilet bowl using a piece of cloth or sponge — it will help you install the new flange effortlessly.

Step 4: Install New Elements

Now it’s time to set the new flange. Place it on the hole where the old flange used to be and screw the flange bolts. Put the new wax ring on top of the flange — you will see the edges where the wax seal sits. 

The new flange and its wax ring make a strong base for the toilet bowl, making sure that it doesn’t move or wobble. 

Step 5: Re-Install the Bowl

Continue by re-installing the toilet bowl. 

Lift the bowl and place it over the new flange, but make sure that base holes match the position of the mounting bolts. Insert the bolts in the holes and screw the nuts that connect the bolts to the toilet base. 

However, don’t push it too hard, or else you might crack the bowl. 

After that, you can reset the other elements of the toilet: the tank, the supply line, and the metal hosepipe. Attach the hosepipe to the shutoff valve and you’re ready to open it.  

Turn on the shut-off valve by twisting it counterclockwise. It will let water flow back into the tank.

Step 6: Test the Toilet

Finally, you can test the new elements to see if the toilet wobbles again. If you do everything right, your toilet will not rock back and forth again.

Tools You’ll Need

Although it’s a simple DIY project, you’ll need a few tools to solve the wobbling toilet problem.

To Fix a Loose Toilet

To Change the Flange

The Bottom Line

Now you know what to do if your toilet moves back and forth.

The solution is easier if you only need to tighten the bolts or insert the shims. Replacing the flange is a bit harder, but we know you can handle it following our instructions. 

Home renovation and bathroom remodeling projects are easy with Bomisch, so make sure to check more posts!


How can you fix a wobbly toilet base?

The first solution to fix the rocking toilet is to tighten the base bolts with a wrench. The second option is to insert plastic shims to fill the gaps between the bathroom floor and the bowl.

If that doesn’t work, you need to replace the flange.

Why does my toilet wobble?

Your toilet wobbles because of the bumpy bathroom floor or loose bolts. The third option is a worn-out flange. In that case, you need to replace this element to make the bowl steady again.

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