Protect people before finishes
Keep people away from wet electrical equipment, sagging ceilings, contaminated water, and unstable finishes. If there is an electrical, structural, gas, or sewage hazard, leave the area and use the appropriate emergency service rather than entering it.
Move possessions only when the path is safe. A ceiling, wall, or floor can hold more water than the visible stain suggests.
Stop the water only at a known safe control
Close the affected fixture or appliance valve if it is clearly identified, accessible, and safe to reach. Use the building shutoff only if you know its location and operation; do not force a seized valve or reach through water near electricity.
Stopping use of the suspected fixture can provide a useful clue. If the flow continues with that fixture off, the source may be elsewhere.
- Note what was running before the leak appeared.
- Photograph the first wet area and accessible piping.
- Record whether the flow changes after a safe shutoff.
Describe the symptom, not a guessed repair
Share the first visible location, whether water is still active, which valves were used, and what sits above or beside the wet area. Those facts help plan access and diagnosis.
A stain can be downstream from the source. Leak detection should narrow the path before a repair or finish opening is promised.