How to Prevent Frozen Pipes: A Winter Checklist for Homeowners
By EasyToFix Homes Team
When water freezes, it expands by about nine percent, and that expansion can split a pipe wide open. A burst pipe can release hundreds of gallons per hour into walls, ceilings and floors, making frozen pipes one of the most expensive winter disasters a homeowner can face. The frustrating part is that prevention is cheap and mostly common sense. Pipes freeze when they sit in unheated space during sustained cold, and every measure below targets that single cause. Work through this checklist before the first hard freeze, and your plumbing will ride out the winter safely.
Why pipes freeze, and which ones freeze first
Water in a pipe starts forming ice around 32 degrees Fahrenheit, but a pipe usually needs several hours of exposure below about 20 degrees to freeze solid and burst. The danger zone is any pipe in unconditioned space: exterior walls, attics, crawl spaces, garages and unheated basements.
The highest-risk pipes are outdoor hose bibs, supply lines in exterior walls, and pipes in cabinets on exterior walls. Pipes deep inside a well-heated home almost never freeze. Your prevention effort should concentrate on the cold spots, not the whole house.
1. Insulate exposed pipes
Foam pipe insulation sleeves are the cheapest protection you can buy. They slip over exposed pipes in basements, crawl spaces, attics and garages, and they slow heat loss enough to keep water above freezing through most cold snaps.
For the coldest spots, use thermostatically controlled heat tape or heat cable, which warms the pipe automatically when temperatures drop. Install it exactly as the manufacturer instructs, never overlap it on itself, and cover it with insulation for the best result. Unplug damaged heat tape rather than trying to repair it.
2. Seal air leaks near plumbing
Cold air blowing directly on a pipe defeats insulation fast. Walk the perimeter of your basement, crawl space and garage, and seal gaps around dryer vents, wiring, pipes and foundation cracks with caulk or expanding foam.
Pay special attention to where pipes pass through exterior walls and rim joists. A small draft in these spots can freeze a pipe even when the rest of the space stays above freezing. Sealing air leaks also cuts your heating bill, so this step pays for itself.
3. Disconnect and drain outdoor hoses
Before the first freeze, disconnect every garden hose, drain it and store it indoors. A connected hose traps water in the hose bib and the pipe behind it, which is one of the most common causes of burst exterior pipes.
If your hose bibs have interior shutoff valves, close them and open the outdoor faucets to drain the remaining water. Consider frost-free hose bibs if yours freeze repeatedly. They shut the water off deep inside the heated wall instead of at the exterior surface.
4. Keep the heat on, even when you travel
Never set the thermostat below 55 degrees Fahrenheit when you leave the house in winter, even for a weekend. The money saved by dropping the heat lower is tiny compared to the cost of a burst pipe.
For longer trips, ask someone to check the house daily and leave cabinet doors under sinks open so warm air reaches the pipes. A smart thermostat that alerts you if the indoor temperature drops is cheap insurance for a home you leave empty during the week.
5. Let faucets drip during extreme cold
When the forecast calls for sustained temperatures below about 20 degrees, let the faucet farthest from where water enters the house drip slowly. Moving water is much harder to freeze than standing water, and the drip relieves pressure that builds up behind any ice that does form.
It is the pressure, not just the ice, that bursts pipes. A slow drip keeps a path open so expanding ice cannot pressurize the section between the freeze and a closed faucet. Catch the drips in a bucket if you would rather not waste the water.
6. Open cabinet doors under sinks
Pipes under kitchen and bathroom sinks often run along exterior walls. Opening the cabinet doors lets warm room air circulate around them during cold snaps.
If you have small children or pets, move cleaning products out of the open cabinets first. This simple habit costs nothing and protects some of the most freeze-prone pipes in the house.
7. Know where your main shutoff valve is before you need it
If a pipe does burst, the first thing you must do is stop the water. Find your main shutoff valve now, while nothing is wrong, and make sure it actually turns. Valves that sit untouched for years can seize.
The main valve is usually where the water line enters the house: in the basement, crawl space, garage or a utility closet. Tag it, show every adult in the household where it is, and keep a shutoff wrench nearby if your valve is the curb-side type.
8. Know what to do if a pipe freezes anyway
If a faucet produces only a trickle or nothing at all during a cold snap, you may have a frozen pipe. Keep the faucet open, then warm the frozen section with a hair dryer, heating pad or towels soaked in hot water, working from the faucet back toward the coldest section. Never use an open flame or a propane heater on a pipe.
If you cannot find the frozen section, if the pipe has already burst, or if warming does not restore flow, shut off the main valve and call a plumber. A frozen pipe that thaws on its own can still leak at a split you cannot see.
When to call a plumber
Call a plumber before winter for an inspection if your home has a history of frozen pipes, unheated crawl spaces or old plumbing in exterior walls. A professional can add insulation, install heat cable correctly and reroute the most vulnerable lines. During winter, call immediately if a pipe bursts, if you cannot locate a frozen section, or if warming a frozen pipe does not restore water flow. Fast action limits water damage, and a plumber can also check for hidden splits that only start leaking once the ice thaws.