Burst pipe and active water damage

A pipe almost always bursts for the same handful of reasons: freezing inside a poorly insulated wall, a galvanized fitting eaten away from the inside, or water hammer that finally splits a joint that was already weak. The result is the same either way — water that won't stop until someone closes the main shut-off.

A burst pipe shows itself as water that keeps running, often audible before it's visible, with a stain that visibly spreads across a ceiling or wall. That's different from a slow fitting leak, which weeps rather than runs, and different again from a sewer backup, which comes up through the basement floor drain rather than down from a wall or ceiling. The distinction matters: closing the main shut-off stops a burst pipe, but it does nothing for a backup.

The priority isn't the repair, it's stopping the water and protecting whatever's underneath it: the electrical panel, the fuse box, anything sitting on the floor. A plumber on the way confirms the shut-off is actually closed first, then works out whether the split section can be cut out and replaced on the spot or whether a wall needs to come open.

Once the water is off, repairing one localized section is usually a single visit. Damage that's spread further — a ceiling in the unit below, a warped floor — is beyond what a plumber's mandate covers and is really a job for a restoration specialist or your insurer, who we'd recommend you photograph everything for before any cleanup starts.

In a Montreal triplex, the main shut-off is often shared by all three units and sits in a narrow basement corner, sometimes behind stored boxes or on the far side from the outside staircase you have to come down first to reach it. A pipe that bursts on the second or third floor often travels through two floors before anyone notices, so the visible damage in your unit doesn't necessarily show where the problem started. In a narrow laneway with no easy parking, the plumber may also lose a few minutes getting equipment down to the basement by the spiral staircase common to the area.

Price mostly comes down to three things: access to the split section (an exposed pipe repairs faster than one behind a closed wall that has to be opened), the hour of the call (the after-hours premium applies evenings, nights, weekends and holidays), and how long the water ran before it was shut off. Water closed quickly keeps the repair to the pipe section itself; water left running longer adds damage to drywall, flooring or the ceiling below, which is a restoration specialist's job rather than the plumber's.

Before you call, if it's safe to check: note whether the water is already off at the main shut-off or still running, which floor and room the damage is visible in, and whether the water is touching an outlet or the panel. Those three answers let us gauge the urgency over the phone and send the right equipment from the start instead of improvising once someone arrives.

An older triplex often mixes several generations of pipe: cast iron or galvanized near the main shut-off, copper installed sometime in the 1960s to 80s, and sometimes PEX added during a recent renovation. Copper typically bursts from a pinhole corrosion spot after fifteen to twenty-five years of use; PEX, being newer, tends to fail from freezing or a poorly crimped fitting rather than corrosion. You don't need to know the material before calling, but it's why two repairs in the same neighbourhood rarely look alike.