Winter Home Maintenance Checklist: What to Do Before the First Freeze

Winterise your home before the first hard freeze — when overnight lows drop below 32°F (0°C) — by servicing the heating system, insulating exposed pipes, cleaning gutters, sealing drafts, and testing smoke and carbon monoxide detectors. A burst pipe alone costs $5,000 to $15,000 in water damage on average, while the full prevention checklist in this guide costs a few hundred dollars and one weekend. Start six weeks before your area's usual first frost date, and finish the outdoor work before ladders get icy.

Work through this checklist in order — heating, water, roof, drafts, safety — and price any bigger jobs from our guides: the roof replacement cost guide if the roof is near end of life, the insulation cost guide if rooms stay cold, and the Insulation Calculator for how much material an attic top-up needs. Our deck building guide covers the outdoor timber care that pairs with this checklist, and the exterior painting cost guide helps you judge whether peeling paint needs attention before winter weather gets at the wood beneath it.

Heating system: service it before you need it

Book a heating service before the first cold snap, because a furnace that fails on a Friday night in January costs emergency-callout rates and leaves the house cold for a weekend. A standard service costs $80 to $200 and covers burner cleaning, ignition testing, filter replacement, and a carbon monoxide check. Replace the furnace filter yourself every 1 to 3 months during heating season — a clogged filter cuts airflow, raises energy bills by 5 to 15 percent, and can trip the furnace's high-limit safety switch. Keep the thermostat at 68°F (20°C) while you are home and no lower than 55°F (13°C) when you are away, since dropping below that risks frozen pipes in exterior walls.

Bleed radiators that are cold at the top but warm at the bottom — trapped air stops circulation and wastes fuel — and check that no furniture or curtains block radiators or return-air vents. If you heat with a heat pump, clear leaves and ice from the outdoor unit and keep 2 ft (61 cm) of clearance around it, since a blocked unit ices up and runs on expensive backup heat. For homes with a fireplace or wood stove, have the chimney swept once a year ($150 to $300) before the first fire; creosote buildup is the leading cause of chimney fires, and a sweep also spots cracked flue liners before they leak carbon monoxide into the house.

Pipes: stop the freeze before it starts

Insulate every exposed pipe in unheated spaces — basement, crawlspace, attic, garage — with foam sleeves that cost $0.50 to $2 per foot and take minutes to fit, because water expands by about 9 percent when it freezes and that expansion splits copper and plastic alike. Shut off outdoor faucets from the inside valve, open the outside tap to drain the line, and leave it open through winter. Disconnect garden hoses: a connected hose traps water in the faucet, which freezes, cracks the faucet body, and floods the wall cavity on the first thaw — one of the most common and most preventable winter insurance claims.

For pipes in exterior walls that have frozen before, add pipe insulation plus a thermostatically controlled heat cable ($25 to $60 per cable), which switches on near freezing and off when the pipe warms. Know where the main water shutoff is and test it before winter — a seized valve discovered during a burst is useless — and keep the number of a plumber who does emergency calls saved in your phone. If you leave the house empty for more than a day in a cold snap, open cabinet doors under kitchen and bathroom sinks on exterior walls so warm air reaches those pipes, and let the faucet farthest from the main drip at a slow trickle when temperatures fall below 20°F (-7°C).

Roof, gutters, and the ice dam problem

Clean gutters and downspouts in late autumn after the leaves fall, because a clogged gutter overflows, soaks the fascia and foundation, and feeds ice dams at the roof edge. A gutter cleaning costs $100 to $250 professionally or an afternoon with a ladder, gloves, and a bucket. Check that downspouts discharge at least 4 to 6 ft (1.2 to 1.8 m) from the foundation, and add extensions if they dump water at the wall — foundation water in winter freezes, expands, and opens cracks that leak all spring. From the ground, scan the roof with binoculars for missing, cracked, or curling shingles and for flashing that has lifted around chimneys and vents.

Ice dams form when heat escaping through a poorly insulated attic melts roof snow, which refreezes at the colder eaves and backs water under the shingles. The fix is insulation and ventilation, not roof heating cables alone: the attic floor should carry R-38 to R-60 insulation (roughly 12 to 18 in of fibreglass batts, depending on type) and the attic should stay near outdoor temperature, with intake vents at the eaves and exhaust at the ridge. If your roof already carries ice dams every winter, price the insulation work from the insulation cost guide and the Insulation Calculator — it pays for itself in heating savings as well as leak prevention. If shingles are past 20 years for asphalt or the roof leaks in more than one place, the roof replacement cost guide will tell you whether repair or replacement is the honest answer.

Drafts, windows, and doors

Seal drafts before you turn the heating up, because the average home loses 25 to 40 percent of its heating energy through air leaks, and the worst offenders are cheap to fix. On a windy day, hold a lit incense stick near window frames, door frames, attic hatches, and where pipes enter the house — smoke that wavers marks a leak. Apply caulk to fixed gaps ($5 to $10 a tube) and self-adhesive foam or V-strip weatherstripping to moving parts like doors and opening windows ($10 to $30 per door or window), and replace any weatherstripping that is compressed, torn, or no longer springs back.

For single-pane or older double-pane windows that feel cold to the touch, interior window insulation film ($15 to $30 for a kit covering 5 windows) cuts drafts noticeably and peels off in spring without damage. Check door sweeps on exterior doors — a gap of even 0.25 in under a 36-inch door leaks as much air as a 2-inch hole in the wall — and adjust or replace the sweep if daylight shows underneath. Do not seal a house so tightly that combustion appliances starve for air: gas furnaces, boilers, and water heaters need their combustion-air supply intact, and any home with gas appliances should have a carbon monoxide detector on every level.

Safety checks that cannot wait

Test every smoke alarm and carbon monoxide detector monthly and replace batteries twice a year — the clock-change weekends are an easy reminder — because heating season is peak season for both fires and carbon monoxide incidents. Smoke alarms last about 10 years and carbon monoxide detectors 5 to 7 years; check the manufacture date printed on the back and replace any unit past its life, since an expired detector can fail silently. Keep a fire extinguisher rated ABC in the kitchen and near the heating system, check its pressure gauge monthly, and make sure every adult in the house knows how to use it.

Stock a winter emergency kit before the first storm, not during it: flashlights and batteries, a battery radio, bottled water, blankets, a snow shovel, ice melt, and a phone charger that does not need mains power. Keep ice melt on hand — calcium chloride works down to -25°F (-32°C) while rock salt stops working around 15°F (-9°C) — but use it sparingly on concrete less than a year old and keep it off lawns and planting beds. If a storm knocks out power, never run a generator inside a garage or near a window, even with the door open; place it at least 20 ft (6 m) from the house with the exhaust pointing away, since generator carbon monoxide kills within minutes in an enclosed space.

The monthly winter routine

Once winter is underway, a 30-minute monthly routine keeps small problems small. Check the furnace filter and replace it if it looks grey, walk the house after a thaw and look for water stains on ceilings and around windows, and clear snow from furnace and water-heater exhaust vents after every snowfall — a blocked vent shuts the appliance down or, worse, pushes exhaust back into the house. Keep gutters clear of ice buildup at the downspout outlets, and use a roof rake from the ground to pull heavy snow off low roof edges after storms dropping more than 12 in, since wet snow weighs 15 to 20 lb per cubic foot and overloaded roofs sag before they fail.

In spring, close the loop: note what froze, leaked, or cost extra heat this winter and fix it in the off-season when contractors are available and prices are lower. A pipe that froze twice gets insulation and a heat cable in May, not next November. A room that stayed 5 degrees colder than the rest gets its insulation topped up in spring, priced from the insulation cost guide. Winter maintenance is not a single weekend — it is a habit of catching the house's weak points while they are still cheap to fix, and this checklist, run once in autumn and monthly through winter, is the whole system.