How to Prevent Frozen Pipes This Winter: 7 Steps
Insulate exposed pipes, keep heat at 55°F (13°C) or higher, let a faucet drip, and know how to thaw a pipe safely, per the Red Cross.
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A frozen pipe can split open and flood a home, and the damage often shows up only after the ice thaws. The fix is mostly preparation: insulate the pipes that sit in cold places, keep the heat steady, and let a faucet drip on the coldest nights. This guide follows the American Red Cross checklist for preventing frozen pipes, step by step.
Summary
Water has a property that makes winter risky for plumbing: it expands as it freezes, and that expansion puts pressure on the pipe until it can break. The American Red Cross lists the pipes that freeze most often: outdoor hose bibs, swimming pool and sprinkler supply lines, water supply pipes in unheated basements, crawl spaces, attics, garages, and kitchen cabinets, and pipes that run against exterior walls with little or no insulation.
Both hot and cold water pipes in these areas need insulation. The three habits that matter most are insulating exposed pipes before the first freeze, keeping the thermostat at the same temperature day and night, and leaving the heat on at no lower than 55°F (13°C) when you go away in cold weather.
Freeze Protection at a Glance
| Method | What it does | When to do it |
|---|---|---|
| Pipe sleeve insulation | Slows heat loss from exposed pipes | Before the first freeze |
| UL-listed heat tape or cable | Adds heat to exposed pipes | Before the first freeze |
| Open cabinet doors | Lets warm air reach pipes | On cold nights |
| Let a faucet drip | Keeps water moving through the pipe | On very cold nights |
| Steady thermostat, 55°F (13°C) or higher | Keeps the house warm enough to protect pipes | All winter, including trips away |
The table shows that prevention has two halves. The first half is done once, before winter: insulation and heat tape on the pipes you can reach. The second half is a nightly habit during cold spells: open cabinets, drip a faucet, and hold the thermostat steady.
Neither half works alone. Insulation slows heat loss but does not add heat, and a steady thermostat does little for a pipe that sits in an unheated crawl space with no insulation at all.
What to Put on the Pipes
Pipe Sleeve Insulation
A pipe sleeve is a foam tube that fits around a pipe and slows heat loss. The Red Cross advises insulating both hot and cold water pipes in unheated areas, and adding insulation to attics, basements, and crawl spaces so those spaces hold higher temperatures. Measure the pipe diameter before you shop, and cover the full run of exposed pipe, including bends and joints, so no bare section is left to freeze first.
Good fit if: you have exposed pipes in a basement, crawl space, attic, or garage that you can reach by hand.
Heat Tape and Heat Cable
Heat tape, also called heat cable, is an electric product that runs along a pipe and warms it. The Red Cross advises choosing a UL-listed product made for water pipes. Read the maker instructions before you install it, and follow them on how to lay it against the pipe. Heat tape needs power, so it will not help during an outage, which is when insulation and a steady thermostat matter most.
Good fit if: a pipe has frozen before despite insulation, or it runs through a spot that stays cold all winter.
Outdoor Faucet Covers and Hose Shutoff
Outdoor hose bibs are among the first pipes to freeze, so they need attention before the first cold night. Remove and store hoses used outdoors. Close the inside valve that supplies each outdoor hose bib, then open the outside bib to let the water drain.
A foam faucet cover adds a layer of insulation on the outside bib. Drain water from swimming pool and sprinkler supply lines following the maker or installer directions. Do not put antifreeze in these lines unless directed, because antifreeze is harmful to people, pets, wildlife, and landscaping.
Good fit if: your home has outdoor faucets, a sprinkler system, or a pool supply line.
If a Pipe Freezes
- Keep the faucet open: if you turn on a faucet and only a trickle comes out, suspect a frozen pipe, and keep the faucet open so water can flow through the frozen area as it melts.
- Apply gentle heat to the frozen section: use an electric heating pad wrapped around the pipe, an electric hair dryer, a portable space heater kept away from flammable materials, or towels soaked in hot water, and keep applying heat until full water pressure is restored. Never use a blowtorch, kerosene or propane heater, charcoal stove, or other open flame device.
- Check every other faucet in the home, because if one pipe froze, others may have frozen too. Call a licensed plumber if you cannot locate the frozen area, if it is not accessible, or if you cannot thaw the pipe.
Before the First Freeze
- Walk the house and list every pipe in an unheated area: basement, crawl space, attic, garage, and kitchen and bathroom cabinets on exterior walls.
- Insulate both hot and cold water pipes in those areas, and add insulation to the attics, basements, and crawl spaces themselves.
- Disconnect and store outdoor hoses, close the inside valves to outdoor bibs, and leave the outside bibs open to drain.
- Keep the garage door closed in cold weather if water supply lines run through the garage.
- Find the main water shutoff valve now, so you can reach it fast if a pipe bursts.
- Set a reminder to keep the thermostat steady on cold nights, and to leave the heat at 55°F (13°C) or higher when you travel in winter.
- If the power goes off or you plan an extended leave, the U.S. Department of Energy advises draining the pipes: turn off the water heater and the main water supply, open all faucets, and let the system drain.