A supply line under a bathroom sink is about the width of a pencil, and when one lets go it moves roughly four gallons a minute. That is not a dramatic number until you multiply it: twenty minutes is eighty gallons, and eighty gallons through a second-floor unit is a ceiling on the floor below.
The difference between a mop and a five-figure claim is almost never how fast we arrive. It is whether anybody in the unit knew where the valve was.
Do it at move-in, not at 2am
Nobody learns a floor plan while standing in water. Walk it once on a dry afternoon and it takes four minutes:
- Find the unit main. Utility closet, under the kitchen sink, or near the water heater. Turn it off, run a tap until it stops, turn it back on. If it will not budge, that is a work order today, not an emergency later.
- Find the fixture stops. Every toilet and sink has its own small valve behind or beneath it. These are what you reach for when you can see exactly what is leaking.
- Label the main. A strip of tape saying WATER MAIN is the cheapest insurance in the building.
What to do while you wait
Once the water is off, the job changes from stopping a leak to limiting what it soaked. Pull what you can off the floor, get towels down at the doorways to keep it in one room, and open the cabinet doors under the sink so the cavity can dry instead of holding water against the particle board.
The units that come out of this cheapest are always the ones where somebody found the valve in the first two minutes.
If you manage a building and want this walked with new tenants as part of the move-in inspection, tell us and we will build it into the checklist. It takes four minutes and it is the single highest-return thing on the sheet.
