The Preventable Disaster
Frozen pipes are one of the most consistently avoidable home disasters — and one of the most costly when they occur. Water expands approximately 9% when it freezes. When water freezes inside a pipe, the pressure it creates can burst the pipe wall at any point in the run, with the burst often occurring not at the frozen section itself but downstream of it where pressure accumulates. The subsequent thaw releases water through the burst into the wall cavity, ceiling, or floor — often undetected for hours.
The average insurance claim for pipe-burst water damage exceeds $10,000. The preventive measures cost a fraction of that and require only awareness of which pipes are at risk.
Which Pipes Are Actually at Risk
Not all pipes in a home are equally vulnerable to freezing. Pipes in heated interior spaces — within conditioned walls, in basements with heat sources, under insulated floors — rarely freeze even in extreme cold. The vulnerable pipes are those in spaces that lose heat to the exterior: uninsulated exterior wall cavities, crawl spaces without adequate heat, attic runs (sometimes used for supply to upper-floor fixtures), unheated garages, and pipes near exterior doors with inadequate insulation.
Identify your home’s vulnerable runs before winter. A pipe that runs through an exterior wall with inadequate insulation on the exterior-facing side, or that runs through an unheated space, is your risk. These are the pipes that need preventive attention.
Preventive Measures Ordered by Effectiveness
The most effective prevention: add insulation to the space where vulnerable pipes run, eliminating the temperature drop. Insulating a crawl space or an exterior wall cavity is a one-time investment that permanently protects the pipes within it. For existing construction where adding insulation requires wall opening, pipe heat tape (electric resistance heating cable applied to the pipe surface) provides continuous protection in the at-risk run.
For the coldest nights: open cabinet doors below kitchen and bathroom sinks on exterior walls (to allow conditioned air to reach the pipe space), allow a trickle of water to run from faucets fed by vulnerable pipes (moving water resists freezing), and ensure heating system thermostats are not set below 55°F even when the home is unoccupied.
If a Pipe Freezes: What to Do and What Not To
If you turn on a faucet in cold weather and get little or no water, a pipe is likely frozen. The correct response: locate the main water shutoff and close it immediately (in case the pipe has already burst — the shutoff prevents flooding when the pipe thaws). Then gently thaw the frozen section with a hair dryer (not a propane torch, which creates fire risk and can melt pipe fittings) working from the faucet end toward the frozen section.
Never leave a frozen pipe unattended while thawing and never use open flame. Keep the faucet open while applying heat — as the ice melts, water needs to escape. Once flow is restored, inspect the entire run carefully for signs of bursting (wet insulation, dripping from the pipe body) before restoring main water supply.
Vacation and Vacancy: The Highest-Risk Period
Home pipes freeze most commonly when homes are unoccupied — during winter vacations, between tenants in rental properties, or during extended owner absences. The heating system runs less or is set lower; nobody notices the warning signs; the frozen section has hours or days to burst and leak before discovery.
Never set the thermostat below 55°F in an occupied or recently occupied home during winter. Drain the water supply system completely if the home will be unoccupied for an extended period in a cold climate — this is the absolute freeze protection that no other measure equals. Draining requires shutting the main, opening every faucet to drain supply lines, and flushing toilets to empty tank and bowl. This leaves nothing in the pipes to freeze.