Common toilet problems and what causes them
| What happens | Usual cause |
|---|---|
| Runs constantly or refills on its own every few minutes | Worn flapper letting water seep into the bowl, or a fill valve set too high and spilling into the overflow tube |
| Water on the floor around the base | Failed wax ring or loose closet bolts, often after the toilet started rocking |
| Water under the tank | Leaking tank-to-bowl gasket or bolts, or a cracked tank |
| Weak flush, needs 2 flushes | Low tank water level, a short flapper chain, or mineral buildup in the rim holes and siphon jet |
| Clogs often | Older low-flow model with a weak flush, or a partial blockage further down the drain |
| Toilet rocks when you sit | Loose bolts, a broken flange, or a soft subfloor from a long-term leak |
| Gurgles when another drain runs | A main line or vent problem; the toilet itself is usually fine |
A toilet that gurgles or backs up when the washer drains is a symptom of a main line clog. That's a drain cleaning job, and replacing the toilet won't fix it.
How toilet repair is done
Running toilet
The plumber checks whether water is leaking past the flapper (a few drops of food coloring in the tank that show up in the bowl without flushing confirm it) or spilling over the overflow tube. The flapper, the fill valve, or both are replaced and the water level is set.
Leak at the base
The toilet is shut off, drained and pulled. The old wax ring is scraped off and the closet flange is checked; a cracked or rusted flange is repaired or replaced.
A new wax or wax-free seal and new bolts go on, and the toilet is reset level and caulked. If the subfloor is soft, it needs repair before the toilet goes back down.
Supply line and shutoff valve
Old plastic supply lines and corroded shutoff valves are a common source of slow leaks and the occasional burst. They're cheap to replace during any toilet repair, with a braided stainless line and a quarter-turn valve.
Repair or replace your toilet?
Repair it if the tank and bowl are intact and the problem is a part. Replace it if the porcelain is cracked, it clogs constantly, or it's an early low-flow model that never flushed well.
New toilets use 1.28 to 1.6 gallons per flush and generally clear much better than the low-flow toilets of the 1990s. Many homeowners also choose comfort-height toilets, which are about the height of a chair and easier to stand up from. Installation includes removing and disposing of the old toilet, a new seal and supply line, and checking the flange.
A running toilet is harder on a septic system
A toilet that runs nonstop can waste hundreds of gallons a day. On public sewer, that shows up as a higher water and sewer bill.
But many homes in unincorporated Cherokee County outside Canton, especially on older rural lots, use septic tanks instead. On septic, all that extra water flows through the tank and into the drain field.
The red clay soil common across the county absorbs water slowly. A drain field that's overloaded every day with clean water from a leaking flapper can saturate and stop accepting water, which shows up as slow drains, soggy ground over the field or sewage odors outside.
A flapper costs very little, while drain field repair costs a great deal. If you're on septic, fix running toilets promptly.
What affects the cost of toilet repair or replacement
- The part. A flapper or fill valve is a small repair; pulling and resetting the toilet is more work.
- Flange condition. A broken or rusted flange, especially on older cast iron drains, adds time and parts.
- Subfloor damage from a long-term leak needs repair before the toilet is reset.
- The toilet you choose. Basic, comfort-height, one-piece and wall-hung toilets range widely in price.
- Shutoff valve and supply line replacement if they're old or corroded.
- Timing. An overflowing toilet at night in a one-bathroom house is an emergency call.
When a toilet problem is an emergency
- The toilet is overflowing and the shutoff valve won't stop it
- Water is leaking through the ceiling below a toilet
- It's the only toilet in the house and it's clogged or unusable
- Sewage comes up in the toilet or a tub when other fixtures drain
Turn the shutoff valve behind the toilet clockwise. If it won't close, lift the tank lid and pull the float up to stop the fill, then shut off the main. Call our 24/7 emergency plumber for overflows that won't stop or backups from the main line.
After a toilet repair
Check around the base and under the tank over the next few days for any moisture. A new wax ring shouldn't leak; if the toilet rocks at all, the bolts need snugging before the seal breaks. Toilet work is one of the most common calls we handle as a plumber in Canton, GA, and it often goes hand in hand with replacing old faucets and fixtures in the same bathroom.
Toilet repair questions
Why does my toilet run by itself every few minutes?
That's called phantom flushing. Water is slowly leaking from the tank into the bowl, usually past a worn flapper, and the fill valve refills it. Replacing the flapper normally fixes it.
Is water around the base of the toilet serious?
It can be. It usually means the wax seal has failed, and every flush is putting a little water under the toilet and into the subfloor.
Have it reset before the floor is damaged. If it smells like sewage, the seal has definitely failed.
How long does it take to install a new toilet?
A simple swap takes an hour or 2. It takes longer if the flange or subfloor needs repair.
Can I use flushable wipes?
It's better not to. Wipes don't break down like toilet paper and are a leading cause of toilet and main line clogs, and they're especially hard on septic systems.