How to Prevent Burst Pipes This Winter

A burst pipe is one of the most expensive things that can happen to a house in winter, and one of the most preventable. The physics are simple: water expands when it freezes, and a frozen pipe builds pressure until something gives — usually a fitting, an elbow, or a section of older pipe. Prevention isn't about one magic fix. It's about removing the conditions that let pipes freeze in the first place.

Insulate exposed pipes

Start with the pipes you can see. Supply lines in basements, crawl spaces, garages, attics, and along exterior walls are the first to freeze because they sit closest to outdoor temperatures. Foam pipe insulation sleeves — the kind that slip over the pipe and seal with adhesive or tape — add a meaningful buffer. They're inexpensive, available at any hardware store, and take an afternoon to install.

Pay special attention to pipes in crawl spaces and unheated garages. Those runs are often completely exposed, and insulating them is the single highest-return prevention step in homes with those layouts. Insulation doesn't make a pipe freeze-proof — in a long sub-zero stretch, even insulated pipes can freeze — but it buys critical hours of protection and keeps moderate freezes from becoming bursts.

Drip faucets during deep freezes

When a hard freeze arrives — especially an overnight plunge or a multi-day sub-zero stretch — let faucets on vulnerable lines drip slowly. Both hot and cold sides matter if both lines run through the cold zone. The drip keeps water moving, and moving water is much harder to freeze than standing water. It also relieves pressure: even if a section does freeze, the open faucet gives expanding pressure somewhere to go instead of building against a closed valve.

Focus on the faucets fed by your most exposed lines — typically the kitchen or bathroom on an exterior wall, or any fixture on the far end of a garage run. A slow, steady drip is enough; it doesn't need to be a stream.

Open cabinet doors on exterior walls

The plumbing under a kitchen or bathroom sink on an exterior wall lives in a cold little box. When the cabinet doors stay closed, warm air from the house never reaches the pipes, and the wall cavity cools toward outdoor temperature. Opening the cabinet doors during a freeze lets household heat circulate around the plumbing.

This matters most in older homes and in any home where the supply lines run up through an exterior wall. If you have a sink that's historically been slow to warm up in winter — you know the one — that's the cabinet to leave open when the temperature drops.

Disconnect hoses before the first freeze

This is the single most skipped step, and the most common cause of burst hose bibs. A frost-proof sillcock — the standard outdoor faucet in modern construction — is designed so water drains out of the pipe after you shut it off. But it can only drain if the hose is disconnected. Leave a hose attached and water stays trapped in the pipe, freezes, and bursts the fitting inside the wall.

Walk the house in early fall and disconnect every hose: front, back, garage, all of them. While you're at it, drain the hoses and store them out of the weather. If your bibs have interior shutoff valves, close them after disconnecting and open the outdoor bib to let residual water drain. Put this on your calendar the same week you check the furnace — once the first hard freeze hits, it's too late.

Know where your main shutoff valve is — before you need it

If a pipe bursts, the difference between a mop-up and a catastrophe is how fast you can stop the water. Find your main water shutoff valve now, while nothing is leaking. In most homes it's in the basement near where the water line enters, in a utility closet, in the garage, or in an underground meter box outside.

Make sure everyone in the household knows where it is and how to operate it. If it's a gate valve that hasn't been turned in years, work it gently — a stuck valve that breaks off when you need it most is its own emergency. Consider tagging it with a bright label so a houseguest or housesitter can find it under pressure.

During a multi-day sub-zero stretch

A single cold night is a warning; a week of sub-zero nights is the real test. During a prolonged freeze:

• Keep the thermostat at a consistent temperature day and night, even if you normally set it back at bedtime. The small energy cost beats a burst pipe.
• Keep garage doors closed, and consider a small heat source in an especially vulnerable crawl space or unheated area — safely, away from anything combustible, following the heater's instructions.
• Check on vulnerable fixtures daily: run water through exterior-wall faucets, look under sinks for frost or condensation on pipes, and walk the basement and crawl space for any sign of moisture.
• If you're unsure whether a pipe has frozen — water slows to a trickle or stops at a faucet — keep the faucet open and warm the area with household heat. Never use a torch or open flame on a pipe.

Vacation-home and empty-house precautions

An empty house in winter is a burst pipe waiting for a calendar. If you'll be away for more than a day or two during freezing weather, the safest move is to shut off the main water valve and drain the lines — open faucets and let the system drain down. For plumbing fixtures, a small amount of antifreeze made for plumbing systems can be added to toilet bowls and drain traps to keep them from cracking. (Never use automotive antifreeze.)

If draining isn't practical, set the thermostat no lower than the mid-50s and have someone check the house regularly — daily during a deep freeze. A smart water-leak sensor near the water heater, under sinks, and in the basement can alert you to a problem while you're gone. An empty house gives a burst pipe hours or days to run; early detection is the entire game.

If a pipe does burst anyway

Even with every precaution, bursts happen — a freeze finds the weak spot you never knew about. When it does, shut off the main water valve first, then get the water out and the structure drying as fast as possible. Every hour of standing water and soaked framing makes the damage — and the repair — worse.

That's where an independent water damage restoration contractor comes in. The contractor locates the burst, extracts standing water, maps moisture through walls and floors, and dries the structure with commercial equipment, documenting everything for your insurance claim. It's a free matching service: call (555) 010-2233 any time, day or night, and we'll connect you with an independent local contractor in your area.