Burst Pipe: What to Do Immediately

1. Shut off the main water supply immediately. The main shutoff is typically at the water meter (outside, near the street) or where the supply line enters the house (basement, crawl space, utility closet, or garage). It's usually a gate valve (round wheel handle) or ball valve (lever handle). Turn clockwise to close (gate valve), or perpendicular to the pipe (ball valve). If you don't know where yours is — find it NOW, before an emergency. Every adult in the house should know.
2. Open the lowest faucet in the house. This drains the water remaining in the supply lines by gravity, reducing the volume of water that continues to exit the burst. For a two-story home, open the lowest floor's faucet (or the outdoor hose bib at ground level).
3. Turn off the water heater. If your water heater is gas, switch the control to "Pilot." If electric, turn off the circuit breaker for the water heater. Reason: an empty tank can overheat and damage the heating element (electric) or create a dry-fire condition (gas).
4. Cut power if water is near electrical panels or outlets. Water and electricity are an electrocution risk. If water is flowing near the electrical panel, outlets, or any electrical appliance, shut off the circuit breaker for those circuits (or the main breaker if you can't safely reach the panel).

Move fast — water migrates further and deeper every minute.

• Move electronics, furniture, rugs, and valuable items away from the affected area.
• Mop, bucket, and towel standing water. The goal is to get it out of the structure as fast as possible — water that sits more than 24–48 hours begins mold growth per EPA mold prevention guidelines.
• Place plastic sheeting over furniture and belongings you can't move.
• Open windows and interior doors to encourage airflow and evaporation — but only if outdoor humidity is lower than indoor humidity.
• If you have a wet-dry shop vac, use it to extract water from carpets and hard floors. Do NOT use a household vacuum cleaner on water — it will destroy the motor.

For ceiling water — if you see a bulge in the ceiling from a leak above, puncture it deliberately at the lowest point with a screwdriver. This sounds counterintuitive but prevents the ceiling from collapsing under accumulated water weight, which causes far more damage than a controlled drain. Put buckets under the puncture point.

Emergency plumbing service (nights, weekends, holidays) typically runs a $150–350 emergency dispatch fee on top of normal labor rates. To get the fastest and most useful response, tell the dispatcher:

• Where the burst is — specific location (e.g., "in the ceiling above the first-floor bathroom")
• What type of pipe if you can see it — copper, PEX, galvanized steel, CPVC
• Whether the main shutoff is now closed
• Whether there's water near electricity
• Whether the pipe is on the supply side (under pressure) or a drain line

A competent emergency plumber will first confirm the main is fully off, locate the break precisely, and give you a scope of repair. Common emergency repairs:

• Slip coupling repair — for a single clean break in a copper or PEX run, a slip coupling replaces a 2–4" segment. Fastest and least expensive ($250–450 labor + parts).
• Temporary repair clamp — a plumbing repair clamp seals a burst to restore partial water service while a permanent repair is scheduled. Not code-compliant for permanent use but buys time.
• Repipe section — if the burst is the result of a corroded or frozen section, the plumber will repipe the vulnerable run rather than just patching the break.

Start documenting immediately — before you mop anything. Your homeowner's insurance claim will go much faster with evidence.

• Photograph the burst pipe itself (if accessible and safe to approach).
• Photograph standing water, wet walls, wet ceilings, and affected personal property.
• Note the date and approximate time you discovered the leak.
• Save the plumber's invoice and any water restoration company invoices.

Standard homeowner's insurance covers sudden and accidental water damage from a burst pipe — this is typically covered. It does NOT cover damage from a slow, gradual leak you knew about and didn't fix ("seepage"), or flooding from outside the home (that's separate flood insurance). Per Insurance Information Institute, water damage is the second most common homeowner's insurance claim — your insurer's claims process is well-established for this.

Call your insurer's claims line as soon as you've addressed the immediate emergency (not in the middle of it). Most insurers have 24/7 claims hotlines and can dispatch a water damage restoration contractor directly.

A burst pipe that flooded even a small area carries significant mold risk if not dried completely within 24–48 hours. Mold begins growing at relative humidity above 60% in water-saturated building materials — drywall, insulation, subflooring, and framing are all vulnerable.

Professional water damage restoration ($1,500–4,500 typically) includes:

• Moisture mapping with thermal imaging to find water behind walls
• Industrial air movers and dehumidifiers (far more powerful than consumer units)
• Removing baseboard and drilling small holes in drywall to allow interior wall cavity drying
• Monitoring moisture readings daily until the structure reaches normal levels (below 15% moisture content in wood)

If you're handling it yourself: rent industrial air movers ($30–50/day each, use 3–5 per room) and a commercial dehumidifier ($40–80/day). Check for wet insulation — wet fiberglass or rockwool insulation must be removed, as it cannot be dried and will harbor mold. Monitor with a $20 moisture meter until readings normalize.

Identifying your pipe material takes 30 seconds and changes what the repair looks like. Here's what you'll find:

• Copper (orange-brown color, dominant pre-2000): the most common supply pipe in existing US housing stock. Bursts typically result from freeze-thaw cycling or corrosion pitting that progresses from pinhole to full split. Per Copper.org plumbing failure data, a single clean split on a sound copper run is repaired with a slip coupling — no soldering on the new section if SharkBite-style push-fit fittings are used. Corroded sections (greenish patina, visible pitting adjacent to the split) require repiping the affected run, not just patching the break point.
• PEX (flexible plastic tubing, red/blue/white, post-2000): more freeze-resistant than copper because it expands before it splits, but not freeze-proof. PEX fails most often at fittings and at points where water is trapped behind a closed valve. The practical upside: repair is faster than copper — no soldering required, and the flexible material works in tight spaces. Per Plastic Pipe Institute — PEX material properties, PEX-A has the highest freeze resistance of the three PEX subtypes.
• Galvanized steel (gray, dull surface, common pre-1970): decades of iron oxide buildup makes galvanized brittle under freeze stress. A burst in a galvanized system is rarely an isolated event — the pipe wall is uniformly corroded, meaning the section adjacent to the burst is likely near failure too. Repairing one section often exposes the next weakest point within months. When a galvanized pipe bursts, treat it as a diagnostic signal for the entire galvanized distribution system, not a one-off repair opportunity.
• CPVC (cream or ivory rigid plastic, common 1975–2000 in Sunbelt markets): cold-temperature embrittlement is a documented failure mode per Plastic Pipe Institute — CPVC temperature performance. Unlike copper or PEX, CPVC can shatter rather than split cleanly when it fails from freeze or impact, leaving jagged edges that require section replacement rather than a simple coupling repair. Crazing (fine surface micro-cracks) on adjacent CPVC is a warning sign that the entire section is embrittled.

Most burst pipe calls end with a slip coupling and a plumber invoice under $600. Some of them are diagnostic events that reveal a system near end of life. Here's how to read which situation you're in:

A single-point repair is the right call when:

• The cause is an isolated freeze event on otherwise sound copper or PEX pipe — no corrosion visible at the repair point or adjacent fittings
• The split is a single clean break on a straight run, not at a fitting or elbow
• The house is under 20 years old — the supply system as a whole has decades of service life remaining

The burst is a symptom, not the problem, when:

• Galvanized steel is present anywhere in the house — any burst on galvanized means the entire galvanized distribution system is at or near end of life. The corrosion is uniform; repiping is the correct decision, not a series of patch repairs over the next few years
• Copper pipe with multiple pinhole leaks in the past 2 years — a single pinhole is mechanical damage; multiple pinholes indicate a dielectric problem or water chemistry (low pH, high dissolved oxygen) that is attacking the pipe system at the material level. The next pinhole will appear elsewhere
• CPVC with visible crazing adjacent to the burst — micro-cracking on the pipe surface indicates systemic embrittlement. The whole run is compromised, not just the section that failed first

Repipe cost context per BuildZoom 2024 repipe cost data: a whole-home repipe to PEX runs $4,500–$15,000 depending on house size and market. A section repipe for a compromised run (e.g., one floor's supply lines, or one wing of a slab-foundation home) runs $800–$2,500. Supply pipe material standards are governed by IPC Chapter 6 — supply pipe materials.

The insurance angle: if your adjuster is already on-site for the water damage claim, ask before the claim closes whether a full repipe would qualify for a homeowner's insurance premium reduction or endorsement in your market. Some insurers offer this in high-risk markets as an underwriting incentive — the window to ask is before the claim file is closed.