1. Toilet Leaking at the Base
The Problem: Water seeping out around the base of the toilet when flushed. This is the most common toilet seal failure and indicates the wax ring or wax-free seal is no longer creating a proper watertight connection.
The Fix: The toilet needs to be removed and the old seal replaced. Turn off the water supply, drain the toilet, remove the mounting bolts, lift the toilet straight up, scrape away all old wax, inspect the flange for damage, install a new seal, and reset the toilet. Use an extra-thick wax ring if the flange sits below floor level.
2. Sewer Gas Smell Around Toilet
The Problem: A rotten egg or sewage smell near the toilet. This means sewer gases are escaping through a failed seal or an improperly seated toilet.
The Fix: Check if the toilet rocks or moves — if so, the seal is compromised. The wax ring may not have compressed evenly. Remove and reinstall with a new seal, ensuring the toilet is lowered straight down without twisting. Tighten bolts evenly on both sides. Never reuse an old wax ring.
3. Toilet Rocking or Unstable
The Problem: The toilet shifts or rocks when you sit on it. This can break the seal over time, leading to leaks and floor damage.
The Fix: First, check if the floor is level. If uneven, use plastic shims (never wood — it rots). Tighten the closet bolts, but don’t overtighten — this can crack the porcelain. If rocking persists, the flange may be too high or too low. Use a flange extender or spacer kit as needed.
4. Toilet Won’t Flush Properly
The Problem: Weak flush, double flushing required, or water continuously running. While often a fill valve or flapper issue, a blocked or misaligned seal between the tank and bowl can also cause poor flush performance.
The Fix: Check the tank-to-bowl gasket (the large rubber seal between the tank and bowl). If it’s cracked, hardened, or misaligned, replace it. Also check the flush valve flapper for warping or mineral buildup. Replace both as a set for best results.
5. Flange Below Floor Level
The Problem: After installing new flooring (tile, vinyl), the toilet flange is now recessed below the finished floor. A standard wax ring won’t seal properly, leading to leaks.
The Fix: Three options: (1) Use an extra-thick/reinforced wax ring designed for recessed flanges, (2) Install a flange extender kit to raise the flange to floor level, or (3) Use a stacked wax-free rubber seal designed with extra height. Never stack two standard wax rings — they can shift and create gaps.
When to Call a Professional vs DIY
If the flange is cracked or broken, call a plumber — this requires pipe work. For simple seal replacement, confident DIYers can handle the job in under an hour with basic tools.
Prevention Tips
- Replace the wax ring or seal every time you remove the toilet
- Tighten loose bolts as soon as you notice rocking
- Inspect the toilet base annually for signs of moisture
- Use quality seals from ISO-certified manufacturers
Sunwell Sanitary manufactures premium toilet seals — wax rings, butyl rubber seals, and foam gaskets — all ISO 9001 certified. Request samples or pricing →