The first move is mechanical: close the main shutoff. Every gallon after that decision is a gallon that does not need drying, and the shutoff is the one tool every homeowner should be able to find in the dark. If water has reached outlets or appliances, cut power to those rooms at the breaker before wading in.
In Norwalk the first hour adds one step to the standard three: after the shutoff and the photographs, look at the pipe you can see, in the garage, at the water heater, under a sink. If the exposed runs show heavy thread rust and flaking, tell the plumber that on the call, because it changes the visit from a patch to an assessment with a patch included. Keep the failed section when it is cut out. On a burst claim and on a repipe decision alike, that piece of pipe is evidence.
The second move is evidence: photographs of the failed line, the rooms, and the water's reach, taken before anything is moved or mopped. Insurers approve documented sudden losses; undocumented ones get argued. Note the time you found it and the time the water stopped.
The third move is the repair read: a split is a symptom with a cause (freeze, corrosion, pressure, age), and the repair visit should name the cause, because a patched effect with a live cause is next season's burst in a nearby section of the same run.
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