A hard freeze warning can make you second-guess every pipe, filter, and vent in the house. Most winter damage starts with a handful of tasks that got skipped in the fall.
This winter home maintenance checklist covers what to do before the first freeze, what to keep watching once cold weather settles in, and the first steps to take if a pipe freezes.
What Should You Do Before the First Freeze?
Five tasks protect your home before temperatures drop below freezing: insulating exposed pipes, draining outdoor faucets, servicing the furnace, checking backup heat sources, and testing carbon monoxide detectors. Most are quick, and each one prevents a problem that costs far more to fix later.
Insulate Pipes in Unheated Areas
Pipes in basements, crawl spaces, attics, and garages are the most likely to freeze because they sit in unheated air. Water expands as it freezes, and that pressure can break metal or plastic pipes, according to the American Red Cross.
Wrap exposed pipes with pipe sleeves, UL-listed heat tape, or heat cable, all of which the Red Cross lists as options. Pay attention to pipes running along exterior walls with little insulation behind them, since those can freeze even in finished rooms. The same prep belongs in your regular plumbing maintenance routine, along with knowing exactly where your main water shutoff valve is.
Sign it's already a problem: a faucet that produces only a trickle when you turn it on. The Red Cross says to suspect a frozen pipe when that happens.
Shut Off and Drain Outdoor Faucets
Outdoor hose bibs are the most exposed water lines in the house. Close the indoor valve that feeds each outdoor spigot, then open the outside faucet to let the remaining water drain. The Red Cross recommends leaving that outside valve open so any water left in the pipe can expand without breaking it.
Remove, drain, and store garden hoses too. A hose left attached can hold water against the spigot.
Check the Furnace Filter and Schedule Service
ENERGY STAR recommends inspecting, cleaning, or changing furnace and heat pump filters once a month and having the heating system checked in the fall. A dirty filter can raise energy costs and damage the equipment, leading to early failure.
- Check the filter now and replace it if it looks gray or clogged.
- Set a monthly reminder so you never have to guess when you last changed the filter.
- Book a professional inspection if the furnace has not been serviced this year.
A furnace that fails on the coldest night of the year often has a warning behind it, like a clogged filter or an inspection that kept getting pushed off.
Check Backup Heat and Generator Readiness
If you rely on a portable generator or space heater during outages, test it before a storm. The Consumer Product Safety Commission (CPSC) warns that one generator produces as much carbon monoxide as hundreds of cars and should never run indoors or in a garage, basement, or shed.
In its January 2026 winter storm warning, the CPSC says to run generators outside only, at least 20 feet from the house, with the exhaust pointed away from your home. Opening doors or windows will not provide enough ventilation. For portable heaters, keep all sides at least three feet from beds, curtains, sofas, and anything else that can catch fire, plug electric models straight into a wall outlet, and never leave one running unattended.
Test Carbon Monoxide Detectors
Press the test button on every carbon monoxide alarm in the house and replace the batteries if needed. The CPSC's CO alarm guidance says to install alarms on each level of the home and outside sleeping areas, and not in attics or basements unless someone sleeps there. Testing CO alarms monthly fits easily into the same smoke alarm maintenance schedule you already keep.
The CPSC names home heating equipment and portable generators among the top sources of deadly carbon monoxide, and more than 200 people die each year from non-fire CO poisoning tied to consumer products. CO has no smell or color, so a working alarm is how you find out it's there.
What Should You Keep Checking During Winter?
Four conditions need regular attention once cold weather settles in: ice buildup on the roof, snow blocking vents, rising indoor humidity, and drafts around doors and windows. None of these are one-time fixes, so check each one every week or two throughout the season.
Watch for Ice Dams and Roof Leaks
An ice dam forms when heat escaping through your roof melts snow, which then refreezes at the colder eaves and traps water behind it. That trapped water can back up under your shingles and into your ceiling.
Look for heavy icicles along the gutter line or a ridge of ice building up at the roof edge. Inside, check ceilings near exterior walls for yellow staining or peeling paint, which can mean water is already getting in. A roof maintenance checklist helps you catch the attic and gutter problems that make ice dams worse.
Keep Heating and Exhaust Vents Clear of Snow
Snow piled against an exterior vent can trap carbon monoxide inside your home. The same CPSC winter storm warning advises clearing snow away from the outside vents of fuel-burning appliances such as furnaces so CO does not build up in the house.
Walk the outside of your house after each snowfall and clear any furnace vent, flue, or dryer exhaust that looks blocked. It takes a few minutes and removes a real safety risk.
Adjust Indoor Humidity When Condensation Appears
Water collecting on the inside of your windows means your humidity is set too high for the outdoor temperature, according to the EPA. The EPA's moisture guidance includes an ASHRAE table of maximum indoor humidity levels that drop as it gets colder outside.
| Outdoor Temperature | Maximum Indoor Humidity |
|---|---|
| +20°F | 35% |
| +10°F | 30% |
| 0°F | 25% |
| -10°F | 20% |
| -20°F | 15% |
If you run a humidifier, turn it down when you notice condensation. Use bathroom and kitchen exhaust fans after showers and cooking to send moisture outside, not into the attic.
Check Doors and Windows for Drafts
A draft around a door or window frame often means the gap between the frame and the wall was never sealed. In Oak Ridge National Laboratory testing cited by the Department of Energy's Building Science Education program, windows with 3/4-inch rough opening gaps had an equivalent leakage area of 28.2 cm²/m², which dropped to 0.5 cm²/m² when the gap was sealed from the interior side of the wall.
Hold a hand near the edges of doors and windows on a windy day. If you feel moving air, weatherstripping or caulk can often close the gap without replacing the window. The EPA also notes that caulking around windows keeps the interior glass warmer and reduces condensation.
What Should You Do If a Pipe Freezes?
If a pipe has cracked, shut off the water at the main valve first. If it's frozen but intact, keep the faucet open and apply gentle heat until full water pressure returns. Call a licensed plumber when you can't find, reach, or thaw the frozen section.
Shut Off the Water If You Find a Leak
A frozen pipe that has already cracked will start leaking as it thaws. If you see water pooling near a pipe or a wet spot on a wall or ceiling, turn off the main water supply before doing anything else.
Find that valve before an emergency, while you have time.
Keep the Faucet Open
Turn on the faucet connected to the frozen pipe, even if nothing comes out. The Red Cross explains that as the frozen area begins to melt, water will begin to flow through the open faucet.
Warm the Pipe Gently and Know When to Call a Plumber
The Red Cross lists four safe heat sources: 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. Never use a blowtorch, kerosene or propane heater, charcoal stove, or any other open flame device.
- Apply heat to the frozen section until full water pressure returns.
- Check every other faucet in the house for additional frozen pipes.
- Call a licensed plumber if you can't find the frozen area, can't reach it, or can't thaw the pipe.
Keep Your Winter Plan Ready for the Next Freeze
A winter plan only helps if you can find it fast when a freeze warning shows up. Write down where the main shutoff valve is, what filter size your furnace takes, when it was last serviced, and which plumber or HVAC contractor you'd call after hours.
Keep that list next to the rest of your annual home maintenance checklist so next winter starts from where this one left off.
Frequently Asked Questions
What home maintenance should I do before winter?
Insulate exposed pipes, shut off and drain outdoor faucets, check your furnace filter, and test carbon monoxide detectors before the first hard freeze. ENERGY STAR also recommends having your heating system checked in the fall, before you depend on it every night.
How often should I check my home during freezing weather?
Clear vents after every snowfall, and check for ice dams and drafts every week or two through the coldest months. Check indoor humidity whenever condensation forms on windows, and test carbon monoxide alarms monthly.
How can I tell if an ice dam is forming?
Look for a thick ridge of ice along the edge of your roof or heavy icicles hanging from the gutter line. Inside, watch for yellow staining or peeling paint on ceilings near exterior walls, which can mean water has already worked its way under the shingles.
What should I do if a pipe freezes but has not burst?
Keep the faucet connected to the frozen section open, then warm the pipe with an electric heating pad, hair dryer, portable space heater, or towels soaked in hot water until full water pressure returns. Call a licensed plumber if you can't find or reach the frozen area or can't thaw it.
What should I check before leaving my house in winter?
Leave the heat on and set the thermostat no lower than 55°F, as the Red Cross recommends, to keep interior pipes above freezing. Shut off and drain outdoor faucets, confirm you know where the main water shutoff is, and ask someone to check the house if you'll be gone more than a few days.
Get Ready Before the Next Freeze Warning
Save your shutoff valve location, furnace filter size, service history, and emergency contractor numbers in one place, with reminders for monthly filter checks and alarm tests. Start your free Manse home profile and have this year's winter checklist ready for next year too.
