The situation

Illustrative example. Not a real job or customer.

In a two-story house in Fullerton, a faint brown ring appears on the dining room ceiling directly below the kids' bathroom upstairs. It seems to grow on some days and not others. The family showers in that bathroom daily and the children take baths a few nights a week.

  1. The homeowner pencils the stain's edge and starts a symptom log.
  2. Over five days, the stain grows only on the nights the tub was filled for a bath.
  3. With the stain dry, they fill the tub partway, below the overflow, and wait. Nothing appears below.
  4. The next day they fill the tub until water enters the overflow. Within minutes a drip forms on the dining room ceiling.

The results point strongly to the overflow gasket rather than the drain, valve or grout.

Why the evidence was convincing

Daily showers never triggered the leak, which made the valve, shower arm and wall grout unlikely. The partial fill didn't trigger it either, which made the drain seal unlikely. Only water reaching the overflow opening brought the drip back.

With a log and two test results in hand, the homeowner could explain the problem clearly and judge whether a proposed repair matched it.

Repair approaches considered

From inside the tub

  • Some overflow assemblies accept a front-installed gasket
  • No ceiling opening needed
  • Depends on the assembly in this tub

Through the ceiling below

  • A small opening under the tub's drain end
  • Lets the whole overflow and drain assembly be inspected
  • Needs a ceiling patch afterward

How it could be finished

  1. Repair the gasket.Whichever route is used, the gasket is replaced and the overflow tightened to the tub.
  2. Repeat the high fill.The tub is filled above the overflow again while someone watches below.
  3. Dry and wait.The ceiling is left to dry and checked after several more baths.
  4. Patch and paint.Once dry, the stain is sealed with stain-blocking primer and painted.

Questions this example raises

  1. Can the overflow in my tub be reached from the front?
  2. Should the drain shoe be replaced at the same time if it is the same age?
  3. Who will patch the ceiling, and when?

Common questions

Is this a real case?

No. It is an invented example to illustrate a common pattern.

Would every overflow leak look like this?

Many do, but a single-story home may show damage in the wall or floor instead of a ceiling.

Could it have been the drain after all?

The partial fill test made that unlikely, but a plumber would confirm with the assembly exposed.

General information for Fullerton, not a quote or professional advice. In an emergency, call 911.