Water on the bathroom floor near the toilet is an easy thing to wipe up and ignore. It should not be ignored. Whatever the cause, the water is soaking the floor, and a small leak that runs for months can rot a subfloor, loosen tile and grow mold.
Four common sources
Condensation
Cold tank water on a warm, humid day makes the tank sweat and drip onto the floor.
Loose or leaking supply connection
The braided line or shutoff valve behind the toilet drips slowly down the base.
Tank-to-bowl seal
The gasket or bolts between the tank and bowl leak when the toilet flushes.
Failed wax ring
The seal between the bowl and the drain flange leaks when the toilet flushes, often only a little at a time.
Simple checks before you call
- Dry the area completely, including the floor around the base and the supply valve.
- Wrap dry toilet paper around the supply connection and shutoff and look for dampness after a few minutes.
- Flush and watch where water first appears. Water at the tank bolts points to the tank seal. Water from under the bowl after flushing points to the wax ring.
- Press gently on the toilet. If it rocks, the bolts are loose or the flange is damaged.
- Check whether the leak happens only after a flush or all the time.
If water appears only after flushing and the supply and tank are dry, the wax ring is the likely cause. A constant leak with a dry bowl base usually points to the supply connection.
Water at the base of your toilet?
Call and tell us when it appears, after a flush or all the time.
How a wax ring replacement works
Shut off and drain
Close the supply, flush and remove the remaining water.
Lift the toilet
Disconnect the supply, remove the bolts and set the toilet aside carefully.
Clean and inspect
Scrape off the old ring and check the flange for cracks or corrosion.
Reset
Install a new seal, set the bowl and tighten evenly.
Test
Flush repeatedly and watch the base.
A toilet is heavy and can crack if tightened unevenly. The flange has to sit at the right height relative to the finished floor. A flange set too low is a common reason a new ring fails.
When the flange is the problem
A flange that is cracked, rusted or separated from the floor will not hold a toilet steady, and a new wax ring will not stay sealed. Repair rings and flange extenders exist, and in some cases the flange must be replaced. This is a task where a plumber's experience shows, because what looks like a simple seal job can turn into a flooring repair.
If the floor around the toilet is soft or discolored, tell the plumber. Subfloor damage affects how the toilet is secured.
When the toilet should be replaced
A cracked bowl or tank leaks no matter what seals are replaced. If the toilet is old, stained inside the tank or wobbles because the porcelain base is chipped, a new one may be more sensible than a repair. See toilet repair and installation for how we decide, or plumbing installation if you are remodeling the bathroom.
What a leak can do if you wait
A toilet base leak is usually small, which is why it gets ignored. The water goes into the floor, not into a bucket. On a wood subfloor, it can soften the boards and the flange screws, and the toilet begins to rock. On tile over a slab, it can loosen grout and tiles and leave a musty smell.
The damage also spreads in ways that are not obvious. Water can wick sideways under flooring, feed mold in a cabinet next to the toilet and stain a ceiling below in a two-story building. Fixing a leak in its first weeks is far cheaper than fixing the floor later.
Why a new wax ring sometimes does not fix it
- The flange sits below the finished floor, so the ring cannot compress against it.
- The flange is cracked or has rusted away from the pipe.
- The toilet was not set level, or the bolts were tightened unevenly.
- The floor is soft and lets the toilet move every time someone sits down.
- A thicker or extra ring was stacked to compensate for a bad flange height, which can fail again.
In those cases, the fix is the flange or the floor, not another ring. A flange extender or a repair ring corrects a low or damaged flange, and a soft floor needs carpentry first. A plumber looks for these problems when the toilet comes up, which is a reason to have an experienced person do the job.
Prevent a repeat
- Do not caulk the entire base of the toilet. A small gap at the back lets a future leak show itself.
- Check the bolts and the base for movement every few months.
- Replace aging supply lines before they fail.
- Wipe condensation from the tank on humid days and consider an insulated tank liner if it keeps dripping.
- Call early if you notice a smell or a stain near the base.
Leaks near the toilet in Monterey Park buildings
Many Monterey Park homes are on concrete slabs, so a toilet leak often wets a tile or vinyl floor rather than a wood subfloor, and the water may travel along the slab edge before it shows up. In condominium and townhome buildings, including newer buildings along Atlantic Boulevard, a toilet leak on an upper floor can show up as a ceiling stain below, which makes it a matter for neighbors and the HOA as well.
If the water seems to appear when no one has used the toilet, check the water meter with all fixtures off. A moving meter can mean a leak elsewhere. The City of Monterey Park's Water Division can answer questions about your meter and account.
Questions about toilet base leaks in Monterey Park
Condensation appears on the outside of the tank and drips even if the toilet is never flushed, especially on humid days. A leak shows after flushing or comes from a connection.
Not usually, but it should be fixed soon. Water damage builds slowly.
Snug bolts help, but overtightening can crack the porcelain. If the leak continues, the seal needs replacing.
Yes, and we check the flange and floor at the same time.
Tell your HOA or property manager promptly. We can provide written findings that help.
Sources and where to confirm
Local facts and rules on this page rest on the Water Division. Confirm anything that affects your own property with the source.
- City of Monterey Park Water Division, for questions about your meter, billing and the utility side of the line.