Burst pipe water damage and what to do first

Water follows framing downward and spreads across the top of ceiling drywall until it finds a seam or light fixture. A sagging ceiling can hold a surprising weight of water, so stay out from under it.

Getting the water out starts with water extraction, and meters then show which walls need structural drying. For cold-weather prevention, keep heat on when you travel and let faucets drip during hard freezes, and read our Connecticut and New Hampshire pages for regional issues.

Freezing is the best-known reason, and the split often appears away from the ice, where pressure builds between the blockage and a closed faucet. Other failures come from corrosion, worn connectors, water pressure that is too high, and old materials such as polybutylene.

Washing machine hoses, toilet supply lines and ice maker tubing fail often too. They are small parts, but they run at full house pressure.

Open the faucet it feeds, then warm the section with a hair dryer or heating pad. Never use an open flame. If you cannot find the frozen spot or reach it, call a plumber. Keep your hand near the valve as it thaws, since a hidden split may only leak once the ice melts.

The plumber fixes the break, and the repair may be needed before drying can finish. The restoration contractor measures and dries the structure, and your adjuster reviews the loss. Keep the failed section of pipe if you can, since it may be useful evidence. Read working with your adjuster before the visit.

Not every failed pipe sprays into a room. Watch for a meter that moves with all fixtures off, a sudden drop in pressure, a damp patch that grows or the sound of running water in a wall. To test the meter, turn off all fixtures and watch the dial for movement.

If you find a leak in a frozen pipe, remember more damage may show only after thawing. Check the whole run, not just the first spot.

See plumber or restoration contractor: who to call first and how to find hidden moisture.

In a house with a basement, the main valve is usually on the front wall, near where the supply line comes through the foundation. On a slab, look in a utility closet, a garage wall or beside the water heater. Crawlspace homes may have it just inside the access hatch. In warm climates the meter and the valve are often outdoors, either against the wall or in a covered box near the street.

Apartments are less predictable. Your unit may have its own valve behind a panel or at the fixtures, and the building's main may be locked in a mechanical room. Call the manager or the maintenance line straight away, and tell your neighbors below that water may be coming through.

Two common valve types work differently. A lever-style ball valve closes with a quarter turn, with the lever sitting across the pipe when shut. A round gate valve takes several turns, and old ones can stick or snap. If it will not move, your water utility may be able to close the street-side valve, which often needs a special key.

A single break in an old system is often a warning about the rest. Galvanized steel corrodes from the inside and narrows over time. Polybutylene, a gray plastic found in homes built from the late 1970s into the 1990s, has a long record of failures at fittings. A plumber can tell you what your house has, and whether spot repairs make sense or a broader repipe is worth discussing.

High street pressure stresses every joint and connector in the house. A simple gauge screwed onto a hose bib will show what the pressure is, and many plumbers treat readings above about 80 psi as too high. A pressure-reducing valve fixes this, and it should be checked if pressure has crept up. Water hammer, the bang you hear when a valve closes fast, is another stress on old pipes.

Tell the plumber about any earlier leaks or repairs, even small ones. A pattern across the same line is more useful to them than the latest break by itself.

A ceiling that bulges has become a container, and wet drywall can give way quickly. Move people and furniture out from beneath it. Do not poke it unless you know the wiring and framing around it and can stand clear, and leave it to the contractor if you are unsure. CDC's guidance is to turn off power at the main when circuits are wet or near water, and to call an electrician instead if you would need to walk through standing water to reach the panel.

Light fixtures are a particular concern because water follows the wire down to them. If a fixture is dripping or a switch sits in a wet wall, keep it off until an electrician has looked at it, and do not test it to see whether it still works.

Early on, the priorities are removing water and opening what has to be opened. Baseboards may come off so that readings can be taken low on the wall, and wet carpet pad may be pulled. Drying equipment then runs while the contractor returns to take readings. The pipe repair often happens early, since drying a house with an active leak makes little sense, though the plumber may need open walls left in place for access or a pressure test.

Toward the end, the equipment comes out in stages as rooms reach their targets, followed by repairs. How long this takes depends on what got wet and how long it sat, and the guide on how long drying takes sets out the factors. Replace drywall only after the framing tests dry, even if the schedule is tempting you to hurry.

Long-running leaks during a trip change the picture. Water may have soaked floors for days, ceilings may have dropped and hot-water heaters may have run empty. Before you go in, consider whether the electricity is safe, and leave the power alone if the panel is in a wet area. Use a flashlight rather than room switches.

Note the date you left and the date you got back, since your insurer will ask. Many policies treat a home that was left unheated differently, and some include conditions for homes left empty. Check for mold as well, because water left for more than a day or two may have started growth. If you do see it, look at mold prevention after water damage before you start moving belongings around.

A failed hot-water line brings an extra set of problems. Steam and warm water raise humidity quickly, which can peel paint, swell doors and send condensation to cold surfaces in other rooms. It can also empty the water heater. Turn off the gas or power to the heater so it does not fire or burn out while empty, and let the plumber relight it when the line is fixed.

Be careful with hot water on the floor, particularly around children. Slab leaks on hot lines often show up as a high gas or electric bill, a warm patch on the floor, or the sound of a heater that runs all the time.

Old houses often have pipes running through plaster walls, and old pipe can be fragile near the break. A plumber may need to open more than expected in order to reach sound pipe to connect to. Ask them to cut as small an opening as they can, and to leave it open for the moisture check afterward. Original trim is worth numbering and setting aside.

If your home was built before 1978, ask about lead-safe practices before old paint gets cut. Dried plaster can sometimes stay in place, though it may need checking for loose areas that have separated from the lath.

Where you live changes burst pipe water damage. See Oregon, Connecticut, Delaware, Kansas, Louisiana, New Hampshire, Chicago, Dallas, Colorado Springs, Cedar Hill, Lake Stevens, Norcross, Port Charlotte, Prosper, Atlanta, Indianapolis.

Go straight to the first steps: emergency burst pipe services, emergency ceiling leak services.