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Quick answer
If your toilet rocks or wobbles, adjust the base by tightening the bolts, add shims under the base if needed, and ensure the wax ring is properly seated. Turn off the water supply before starting.
Confirm the symptom
- Toilet rocks or wobbles when touched
- Water sloshes or spills when toilet is used
- Noise or vibration when flushing
Tools and prep
- Adjustable wrench
- Screwdriver
- Shims (wood or plastic)
- New wax ring (if needed)
- Plumber's putty (optional)
- Turn off water supply
- Protect floor with towels or a tarp
Step-by-step troubleshooting
- Turn Off Water SupplyDo: Locate and turn the shut-off valve clockwise to stop water flow.Observe: Water stops flowing into the tank.Means: The toilet is safely isolated from water.Next: Drain the tank and bowl.
- Drain the Tank and BowlDo: Flush the toilet and hold the flapper open to drain water. Use a sponge or towel to soak up remaining water.Observe: Most water is removed from the tank and bowl.Means: You can work without water interference.Next: Remove the toilet.
- Remove the ToiletDo: Loosen the nuts on the bolts at the base of the toilet using an adjustable wrench. Lift the toilet straight up and place it on old towels.Observe: Toilet lifts off the flange without resistance.Means: The toilet is disconnected from the flange.Next: Inspect the flange and wax ring.
- Inspect the Flange and Wax RingDo: Check the flange for damage or movement. Remove the old wax ring and any debris from the flange and toilet base.Observe: Flange is secure and clean; old wax is removed.Means: You're ready to install a new wax ring.Next: Install new wax ring and shims.
- Install New Wax Ring and ShimsDo: Place shims under the toilet base where needed for stability. Set the new wax ring on the flange, then lower the toilet onto it.Observe: Toilet sits level and stable on the floor.Means: The toilet is properly aligned and sealed.Next: Secure the toilet.
- Secure the ToiletDo: Align the bolts with the flange and tighten the nuts by hand. Use a wrench to snug them, but avoid over-tightening.Observe: Toilet is firmly attached to the flange without rocking.Means: The toilet is securely installed.Next: Restore water supply and test.
- Restore Water Supply and TestDo: Turn the shut-off valve counterclockwise to restore water flow. Let the tank fill, then flush and check for leaks or rocking.Observe: Toilet functions without leaks or movement.Means: The repair is complete and successful.Next: Final check for stability.
- Final Check for StabilityDo: Gently rock the toilet to ensure it's stable. Check under the base for any gaps or leaks.Observe: Toilet remains stable with no movement or water leakage.Means: The toilet is properly installed and sealed.Next: Complete
Common causes
| Cause | Likelihood | Difficulty | Part often needed |
|---|---|---|---|
| Uneven floor The floor isn't level, causing the toilet to rock. | Common | Easy | Shims |
| Loose or damaged bolts Bolts that secure the toilet to the flange are loose or broken. | Common | Easy | Toilet bolts |
| Worn or damaged wax ring The wax ring has deteriorated, causing instability and leaks. | Common | Easy–Medium | Wax ring |
| Damaged flange The flange is cracked or loose, preventing a secure connection. | Sometimes | Medium | Toilet flange repair kit |
| Improper installation The toilet wasn't installed correctly initially. | Sometimes | Easy–Medium | Wax ring, shims |
| Settling of the building The house has settled, causing the floor to shift. | Rare | Hard | Floor leveling compound |
| Excess weight on the toilet Heavy objects on the tank or excessive use can cause the toilet to shift. | Rare | Easy | None |
Parts matching
Common parts needed for this repair include:
- Shims to level the toilet on an uneven floor
- Toilet bolts to secure the base to the flange
- Wax ring to create a watertight seal between the toilet and flange
- Toilet flange repair kit if the flange is damaged
- Plumber's putty (optional) for additional sealing
Purchase a wax-free seal if you prefer a no-mess option, but ensure it's compatible with your toilet and flange.
When to call a professional
- The flange is severely damaged and requires replacement
- The floor is significantly uneven and needs leveling
- You're unable to secure the toilet properly after multiple attempts
- There's a persistent leak after reinstallation
- You're unsure about the correct installation process or parts needed
FAQ
Can I use something other than shims to level the toilet?
Yes, you can use plastic leveling feet or a floor leveling compound if the floor is significantly uneven. Ensure the alternative is stable and won't shift over time.
How often should I check my toilet for stability?
Check your toilet for stability every few years or after any major home events like plumbing work or house settling.
What if the toilet still rocks after adding shims?
If the toilet still rocks, the flange might be damaged or the floor may need professional leveling. Consider calling a plumber for further inspection.
Can I reuse the old wax ring?
No, the old wax ring should be replaced with a new one to ensure a proper seal and prevent leaks.
Is it normal for the toilet to make a slight noise when flushing?
A slight noise is normal, but loud or persistent noises could indicate a loose toilet or improper installation. Check the stability and sealing.