How to Prevent Frozen and Burst Pipes in a New Jersey Winter

A burst pipe is one of the most common and most expensive winter emergencies a New Jersey homeowner can face, and it is largely preventable. A little preparation before a cold snap can save you thousands of dollars in water damage. Here is what makes pipes freeze, why they burst, and a clear checklist to keep yours intact all winter.

At What Temperature Do Pipes Freeze?

Water freezes at 32 degrees Fahrenheit, but pipes do not usually become a real risk until the temperature drops to around 20 degrees or below, especially when it stays that cold for six or more hours. That 20-degree mark is the widely cited threshold where plumbing professionals start to worry.

Duration and location matter as much as the number. A brief dip below freezing may not give pipes time to freeze, while a sustained cold snap, or a poorly insulated pipe against an exterior wall, can freeze in as little as 6 to 12 hours. Pipes with no water moving through them freeze fastest.

Why Frozen Pipes Burst

Here is the part that surprises people: it is not the ice itself that splits the pipe. When water freezes it expands, and as ice forms it pushes the remaining water down the line. If that water hits a closed faucet or a second ice blockage, pressure builds in the trapped section with nowhere to go. That pressure is what ruptures the pipe, often at a point away from the actual ice.

Most burst pipes do their damage not when they freeze, but when they thaw and the water comes rushing out.

That is also why a frozen pipe can stay quiet for days and then flood a home the moment it thaws. Acting early is critical.

Which Pipes Are Most at Risk

Freezing targets plumbing in unheated and exposed spaces. The usual suspects:

• Pipes in unheated areas: basements, attics, garages, and crawl spaces.
• Pipes running through exterior walls or under sinks on outside walls.
• Outdoor hose bibs and sprinkler lines.
• Any line in a space where warm household air does not circulate.

How to Prevent Frozen Pipes

This is your before-the-cold-snap checklist, drawn largely from American Red Cross guidance:

• Insulate exposed pipes in unheated areas with foam pipe sleeves or, for problem spots, UL-listed heat tape or heat cable.
• Disconnect and drain garden hoses, then close the inside valve to each outdoor hose bib and drain it. Leave the outside valve open so any remaining water can expand without bursting the pipe.
• Keep your heat at 55 degrees or higher, even when you are away. This is warm enough to protect pipes in unheated areas.
• Open cabinet doors under sinks (especially on exterior walls) so warm air can reach the plumbing. Move chemicals out of reach of children first.
• Keep the garage door closed if water lines run through it.
• Let cold water drip from faucets served by exposed pipes during extreme cold. A trickle of moving water helps prevent freezing and relieves pressure.
• Know where your main water shutoff is before you ever need it.

Leaving Town for the Winter

An empty house during a cold snap is a classic setup for a burst pipe. If you travel:

• Keep the thermostat at 55 degrees or higher; do not turn the heat off.
• Consider shutting off the main water supply and draining the lines by opening faucets, so there is no standing water to freeze.
• Install a smart leak or temperature sensor that alerts your phone, and ask someone to check the house periodically.

What to Do If a Pipe Freezes

If you turn on a faucet and only a trickle comes out, a pipe is likely frozen. Act before it bursts:

• Keep the faucet open. As you thaw the pipe, running water helps melt the ice and relieves pressure.
• Apply gentle heat to the frozen section with a hair dryer, a space heater, or warm towels, working from the faucet end back toward the blockage.
• Never use an open flame (no blowtorches or propane heaters). It is a fire risk and can damage the pipe.
• Check your other faucets. If one pipe froze, others may have too.
• If you cannot reach or thaw the pipe, call a plumber before it bursts.

What to Do If a Pipe Bursts

If a pipe has already burst, minutes matter:

• Shut off your main water supply immediately, then open faucets to drain the lines and relieve pressure.
• Document the damage with photos and video for your insurance claim before cleanup.
• Call a restoration professional to extract the water and dry the structure before mold sets in. See our water extraction service.

The good news on cost: a burst from frozen pipes is usually considered sudden and accidental, so homeowners insurance often covers the resulting damage, as long as you took reasonable precautions like keeping the heat on. We cover the details in our insurance guide. A plumber’s burst-pipe repair averages around $500, but the water damage left behind can run into the thousands if it is not dried quickly.

Frequently Asked Questions

At what temperature do pipes freeze?

Pipes become a real risk at about 20 degrees Fahrenheit or below, especially when it stays that cold for six or more hours. Exposed or poorly insulated pipes can freeze in as little as 6 to 12 hours.

Should I let my faucets drip in cold weather?

Yes. During extreme cold, let cold water drip from faucets served by exposed pipes. Moving water helps prevent freezing and relieves the pressure that actually bursts pipes.

What temperature should I keep my house to prevent frozen pipes?

Keep your heat at 55 degrees or higher, including when you are away, to protect pipes running through unheated areas like basements, attics, and garages.

What should I do if a pipe freezes?

Keep the faucet open and apply gentle heat with a hair dryer, space heater, or warm towels, working from the faucet end. Never use an open flame. If you cannot reach or thaw it, call a plumber before it bursts.

Does insurance cover frozen pipe damage?

Usually yes, if the burst was sudden and accidental and you took reasonable precautions such as keeping the heat on. The resulting water damage is typically covered, minus your deductible.