How to Fix a Wobbly Toilet in 5 Easy Ways
Last Updated on July 27, 2023 by toilethaven
How Do You Steady a Wobbly Toilet?
A wobbly toilet is not only uncomfortable, but it could also be a health hazard. Fortunately, fixing a wobbly toilet can be a very easy task, one which you will hardly need to call a plumber.
If a rocking toilet is left unfixed for a long time, the wax ring seal will eventually be broken due to the sideways movement, which will make it start leaking. Your problems will be far from over because if your floor is wooden, it will certainly start to rot.
Toilets wobble when they are not firmly secured to the floor. Loose toilet bolts, a broken toilet flange, or an uneven floor cause this. It could also happen if the toilet flange is too high off the finished floor or if the subfloor is soft/weak.
To steady a wobbly toilet, use toilet shims to level it if installed on an uneven floor. Tighten the toilet anchor bolts if they are loose, or replace the toilet flange if broken. If a soft/weak subfloor causes the problem, you need a flooring specialist to fix it.
There is a difference between a wobbly toilet and a rocking toilet seat. A rocking toilet seat is almost always caused by loose mounting bolts. Check out this post on how you can fix it.
A broken toilet wax ring seal will lead to water flooding around the toilet’s base or even a urine/sewer smell inside the bathroom. You might also notice the dampness on the ceiling of the basement.
What Causes a Toilet to Wobble?
Either of the following causes a wobbly or rocking toilet:
- Loose toilet bolts
- The toilet flange is too high off the floor.
- Broken/corroded toilet flange
- Soft and weak subfloor
- Uneven floor
Toilets bolts are the 2 bolts on each side of the toilet bowl which anchor it on the floor. They are hooked on the toilet flange and tightened using nuts. Sometimes these bolts are covered with bolt caps matching the color of the toilet.
A toilet flange is the pipe fitting that connects the toilet bowl to the drainpipe. Old flanges are made of cast iron, but modern ones are made of plastic.
Loose toilet bolts or a broken flange are the ones most responsible for a wobbling toilet. Toilet bolts can be easily tightened, but a broken toilet flange will need to be replaced.
A toilet flange should ideally be 1/4 inch above the finished floor. If the toilet is on an uneven floor, then toilet shims should be used to level it.
How to Fix a Wobbly Toilet
There are a few ways to fix a wobbly toilet, depending on the problem. To fix a wobbly toilet:
- Tighten the toilet bolts.
- Replace the toilet flange.
- Shim the toilet.
- Repair and level the floor.
The first thing to do is to ensure the toilet has no leaks. Carefully check the base of the toilet to see any leaks. If there are no leaks, go ahead and inspect the condition of the toilet bolts.
1. Tighten the Toilet Bolts
Check on each side of the toilet to locate these bolts. Usually, the nuts of the bolts are covered with plastic caps that match the color of the toilet, purely for aesthetics. Use a flathead screwdriver to remove the caps. Check using your hand if the bolts are loose or tight. Confirm with a wrench.
Tighten the bolts if they are loose. If the bolts are more than hand-tight, use a pair of pliers or wrenches and tighten them a little. Always be careful when tightening the toilet bolts not to crack the bowl.
A broken bowl can be repaired. Also, check out the condition of the washers. Sometimes the washers get deformed, which makes the bolts loose and hence a wobbling/rocking toilet.
If the bolt rotates and does not tighten, grab the top of the bolt with a pair of pliers and tighten the nut using an adjustable wrench.
2. How to Shim a Wobbly Toilet
If, even after tightening the toilet, it is still wobbling, it is time to shim it. Use plastic shims and insert them underneath the toilet bowl until the entire toilet is solid on the floor.
Use a knife to trim the protruding ends of the shims. Caulk all around the base of the bowl. Wait for the caulk to dry before using the toilet.
To install the shims properly, start by loosening the toilet bolts, then tighten them once the toilet is no longer wobbling—more information is in this post.
There are people who do not like to caulk the toilet to the floor. There are many reasons why you should caulk your toilet, especially after shimming it.
The main concern is aesthetics and also the fact that you might not notice when your toilet starts to leak. This is, however, not factual.
Read on why you should caulk your toilet on the floor in this post.
3. Replace the Toilet Flange
If you find out that the cause of your wobbling toilet is a broken toilet flange, you will have no option but to replace it.
Replacing a toilet flange will take time, but it is doable. Bringing in a plumber to replace it will cost you way too much, and you are better off doing it alone.
- Adjustable wrench/pliers
- Putty knife
- Flange bolts, nuts, and washers
- Toilet shims
- A small hacksaw
- Flange repair kit/new flange
- Wax ring/ rubber seal
Step 1: Remove the toilet
There are two types of toilets. One-piece toilets and two-piece toilets. One-piece toilets are made as one unit compromising the bowl and the tank. The two-piece toilets are made with separate bowls and tanks and are only joined during installation.
If you have a one-piece toilet, you have no option but to remove it all at once. If, instead, you have a two-piece toilet, you may opt to remove the tank first and then the bowl later. Although this is a long process, it might be the safer one. When you remove them both together, you risk cracking the tank where it is joined to the bowl.
Now proceed to remove the tank as follows:
- Turn off the water shut-off valve. You will find this at the rear wall of the toilet.
- Flush the toilet and hold the flushing lever down to remove all the water in the tank.
- Use the sponge to mop out all the water left in the tank and inside the toilet bowl.
- Disconnect the water supply line from the tank. This line fills the tank with water from the shut-off valve.
- Use the wrench to loosen the two toilet bolts.
- Once the bolts are out, hold the toilet by the bowl and gently rock it to break the wax ring seal.
- Once the toilet is free, lift it off and place it on the newspapers.
- Stuff a rag inside the drain pipe to prevent bad odors from entering the house.
- Use the putty knife, scrape the wax from the toilet outlet, and flange.
- Check if the flange is broken, corroded, or just too old.
- If the flange is defective, go ahead and remove it.
- The flange is screwed to the flooring using screws. Use a screwdriver to remove them.
- Check out also the general condition of the subfloor.
Step 2: Replace the Toilet Flange
If your flange needs repair, use a toilet flange repair kit to perform any repairs needed. There is also the chance that the flange is old and corroded hence unusable. In this case, you must replace it. If the flange is in good condition, you only need to buy bolts, washers, and nuts. A new wax ring must also be used. A wax ring cannot be reused.
The condition of the subfloor can hold you back for some time. You should repair it if wet, soft, or rotten before fixing the toilet. A weak floor will always make a toilet wobble.
Check a detailed article on how to replace a toilet flange here.
Step 3: Replace the Wax Ring
- Before fixing the wax ring, you need to establish that once the toilet is installed, it will not wobble again. You will therefore slot in your two bolts and washers in the flange and install the toilet without the wax ring.
- If you have replaced the flange, be careful with the positions of the two bolts. Always use the clock rule. Assume the flange is a round clock with the back of your toilet at the 12-noon mark. Make sure your bolts are at the 3 and 9 o’clock marks. The toilet must always be perpendicular to the rear wall.
- Once you have your toilet in position, try to rock it to see if it is flush off the floor or if there is a gap. If there are gaps, slide in some shims until the toilet is pretty. Mark the points where you had the shims. Remove the toilet.
- Lay the toilet on its side and slide in a wax ring on its outlet. This method is better than putting the wax ring on the flange and installing the toilet. With this method, you are always sure the wax ring will seal. Alternatively, you can decide to use a rubber seal instead of a wax ring. Just put it on top of the flange and install the bowl.
Step 4: Install the Toilet
- When your wax ring/rubber seal is in place, lift the toilet and align it with the 2 bolts. Slide the bolts through the holes on the toilet base and lay them down gently. Rock the toilet gently to make sure it is solid on the flange and that the wax is sealing.
- Slide in the shims in the spaces you had marked before. You might need to tap them slightly with a small hammer to make sure they go in as much as possible. Trim the protruding ends of the shims.
- Put in a washer and a nut in each of the two flange bolts and tighten alternatingly. It is exceedingly important to tighten the nuts alternatingly to balance the pressure on both sides of the toilet. If you tighten one side before tightening the other, the toilet will slant to one side. Remember not to tighten too much, which can crack the toilet bowl.
- Test the toilet. Sit on the toilet and feel if there is any change. If you are satisfied with the results, then congratulations! You now know how to fix a wobbly toilet.
- Cut off the ends of the toilet bolts just above the nut and cap them off.
- Caulk the base of the toilet and wait for it to dry before using the toilet.
- Reconnect the water supply and enjoy your toilet trips going forward.
Fixing a wobbly toilet can be an easy task or a hard task. In the same light, it can be very cheap or very expensive. If you know how to fix a wobbly or rocking toilet, you can massively reduce costs by avoiding hiring a plumber. A toilet is an essential home appliance that should be comfortable at all times; for you and your guests.
1. How do I fix a wobbly toilet seat?
A wobbly toilet seat is caused by loose mounting bolts. Use your left hand to feel the wingnut underneath the toilet bowl. Hold it and tighten the bolt with a screwdriver. If the bolt head is covered with plastic caps, use a flathead screwdriver to remove them.
2. Can a loose toilet cause a leak?
A loose toilet, if not fixed promptly, will surely cause a leak. Continuous rocking will, after some time, break the wax seal, and flush water will start leaking into the bathroom floor.
3. How do I fix a wobbly toilet tank?
A toilet tank is fixed on top of the toilet bowl. If it is wobbling, it is because the bolts fixing it on the bowl are loose. The best way to tighten these bolts is by making a ¼ turn on each bolt alternatingly. If you tighten one bolt at a time, the pressure will not be evenly distributed, and you risk cracking the tank, or the tank will lean to one side. Make sure each bolt has a washer.