First hour
- Stop the water.Close the toilet supply valve behind the bowl by turning it clockwise. If it will not close, shut the main water valve.
- Contain upstairs.Use towels you will throw away to keep water from spreading further on the bathroom floor. Wear gloves.
- Protect below.Move furniture and belongings out from under the wet area. Put a bucket and plastic sheeting down.
- Photograph both rooms.Show the bathroom floor, the overflow source, and the ceiling stain or drip below.
- Avoid fans and the furnace blower.Moving air can spread contaminated moisture and odor through the house; wait for containment.
What is hidden between the floors
Bathroom water runs to the lowest point it can find. On a tile or vinyl floor that is usually along the base of the toilet, under the baseboard, or through gaps around the tub. From there it soaks the subfloor, drips onto ceiling drywall below, and wets any insulation in the joist bay. If the ceiling below has recessed lights or a vent, water often appears there first.
Because the water carried waste, the materials it soaked are handled as contaminated. The ceiling drywall in the wet area usually comes down, and insulation in that bay is removed. Subfloor and joists are typically cleaned, treated and dried rather than replaced unless they are damaged or deteriorated. The toilet may need to be pulled to dry and inspect the floor under it.
Typical scope by layer
| Layer | Usual handling | Reason |
|---|---|---|
| Bathroom vinyl or laminate | Often removed | Water trapped underneath cannot be sanitized or dried in place |
| Bathroom tile | Often stays; grout and edges checked | Tile is non-porous, but water may sit under it |
| Subfloor and joists | Cleaned, treated, dried | Replaced only if delaminated or rotted |
| Insulation in the joist bay | Removed | Porous and holds contamination |
| Ceiling drywall below | Wet section removed | Porous; often stained and soft |
| Light fixtures and fans | Checked by an electrician | Water inside electrical boxes is a hazard |
Ask before work starts
- How far beyond the visible stain will the ceiling be opened, and why?
- Will moisture readings be taken in the subfloor and joists before closing up?
- Does the toilet need to come off the floor, and who resets it?
- How will the room below be contained during demolition?
- What documentation will be provided for my insurer?
General information for Thornton, not a quote or professional advice. In an emergency, call 911.