How to Winterize Your Home: The Complete Checklist

Skipping winterization costs the average homeowner $500-2,000 per year in higher heating bills, emergency repairs, and water damage from frozen pipes. A weekend of preventive work in October or November prevents all of it.

This checklist covers everything, room by room. Print it, work through it over a weekend, and your home will be ready for whatever winter throws at it.

Heating System (Do This First)

Your furnace or heat pump is the most critical system to check before cold weather arrives. A breakdown in January is expensive, miserable, and avoidable.

Replace the furnace filter. A dirty filter makes your system work 15-20% harder. Replace it now and again mid-winter. Standard filters cost $5-15.

Schedule a professional tune-up. If you haven’t already, this is also a good time to upgrade to a smart thermostat for automatic energy savings. An HVAC technician inspects the heat exchanger, cleans the burners, checks the ignition system, and tests safety controls. Cost: $80-150. This catches small problems before they become $1,000+ emergency repairs. Book early — HVAC companies are slammed by November.

Test the system before you need it. Turn the heat on and let it run for 30 minutes. Listen for unusual noises. Check that warm air comes from all vents. If something seems off, you have time to fix it before temperatures drop.

Bleed radiators (if applicable). If you have hot water radiators, use a radiator key to open the bleed valve on each unit until water flows steadily. Air trapped in radiators prevents them from heating fully.

Check carbon monoxide detectors. Replace batteries and test every detector. If you do not have one near your furnace and on each sleeping floor, install them. CO detectors cost $20-40 and can save your life.

Windows and Doors

Air leaks around windows and doors account for 25-30% of heating energy loss in a typical home.

Check weatherstripping on all exterior doors. Close the door on a dollar bill. If you can pull the bill out easily, the weatherstripping is not sealing properly. Replace it with adhesive-backed foam tape ($5 per door) or V-strip weatherstripping ($8 per door) for a tighter seal.

Install or replace door sweeps. If you see daylight under your exterior doors, add a door sweep. Screw-on aluminum sweeps cost $8-12 and take five minutes to install.

Caulk window gaps. Run your hand around each window frame. If you feel cold air, apply exterior caulk to seal the gap. A tube of silicone caulk costs $5 and seals multiple windows. While you’re at it, check the caulk around your bathtub too.

Consider window insulation film for single-pane windows. This is one of the cheapest eco-friendly home improvements available. Heat-shrink window film kits cost $5-10 per window and reduce heat loss by up to 55% on single-pane windows. Apply the film, then use a hair dryer to shrink it tight. It peels off cleanly in spring.

Lock your windows. Locking the sash pulls the two halves together tightly, reducing the gap where air leaks through.

Plumbing (Prevent Frozen Pipes)

Burst pipes from freezing are one of the most expensive home emergencies, averaging $5,000-10,000 in water damage repairs.

Disconnect and drain outdoor hoses. A hose left connected traps water in the hose bib, which freezes and can crack the pipe inside the wall. Disconnect all hoses, drain them, and coil them in the garage.

Shut off outdoor faucet supply valves. Most homes have an interior shut-off valve for each outdoor faucet. Turn it off, then open the outdoor faucet to drain any remaining water.

Insulate exposed pipes in unheated areas. Pipes in the garage, crawl space, attic, or along exterior walls are vulnerable. Wrap them with foam pipe insulation ($3-5 per 6-foot section). For extreme cold, use heat tape ($15-30) on the most exposed runs.

Know where your main water shut-off valve is. If a pipe does burst, you need to stop the water fast. Find it now, make sure it works (turn it off and on), and label it.

If leaving for vacation: Set the thermostat no lower than 55 degrees F. Open cabinet doors under sinks on exterior walls to let warm air reach the pipes.

Exterior

Clean gutters and downspouts. Clogged gutters cause ice dams, which force water under your roof shingles and into your walls. Clean gutters after the last leaves fall. Make sure downspouts direct water at least 4 feet away from the foundation.

Inspect the roof. Look for missing, cracked, or curling shingles from the ground with binoculars. Fix any damage before snow arrives. A missing shingle is a $20 fix now or a $2,000 leak repair later.

Check the chimney. If you use a fireplace or wood stove, have the chimney inspected and cleaned annually. Creosote buildup causes chimney fires. Cost: $150-300 for a professional sweep.

Trim tree branches near the house. Heavy snow and ice can snap branches onto your roof, siding, or power lines. Trim any branches within 6 feet of the house.

Drain and winterize sprinkler systems. Hire a professional to blow out the lines with compressed air ($50-80) or do it yourself with an air compressor. Water left in sprinkler lines will freeze and crack the pipes.

Store or cover outdoor furniture. Move furniture to a garage or shed, or cover it with waterproof covers. Freeze-thaw cycles destroy cushions, warp wood, and rust metal.

Attic and Insulation

Check attic insulation depth. The Department of Energy recommends R-38 to R-60 for most climates, which translates to 10-14 inches of fiberglass batts or 8-12 inches of blown-in cellulose. If you can see the tops of the ceiling joists, you need more insulation.

Seal attic air leaks. Look for gaps around pipes, wires, ducts, and the chimney chase that pass through the attic floor. Seal them with caulk, spray foam, or metal flashing (around the chimney). These gaps let warm air escape into the attic, wasting energy and contributing to ice dams.

Check attic ventilation. Good attic ventilation keeps the roof cold, which prevents ice dams. Make sure soffit vents are not blocked by insulation and that ridge or gable vents are clear.

Garage

Test the garage door seal. Close the door and look for daylight along the bottom. Replace the rubber seal if it is cracked or compressed flat ($10-20 for a replacement strip).

Insulate the garage door. If your garage is attached to the house, an insulated garage door (or a retrofit insulation kit, $50-100) keeps the adjacent rooms warmer and reduces heating costs.

Move freeze-sensitive items inside. Paint, cleaning chemicals, and canned goods can be ruined by freezing. Move them to a heated space for the winter.

Emergency Kit

Stock a power outage kit:

Flashlights and extra batteries
Battery-powered or hand-crank radio
Blankets and sleeping bags
Non-perishable food and bottled water (3-day supply)
Manual can opener
First aid kit
Fully charged portable phone battery

If you have a generator: Test it now and store fresh fuel. Never run a generator indoors or in an attached garage.

The One-Weekend Plan

Saturday morning: Furnace filter, test heating, check CO detectors, bleed radiators.

Saturday afternoon: Weatherstrip doors, install door sweeps, caulk windows, apply window film.

Sunday morning: Disconnect hoses, shut off outdoor water, insulate pipes, clean gutters.

Sunday afternoon: Check roof and attic insulation, winterize sprinklers, store outdoor furniture, trim branches.

Total cost for a typical home: $50-200 in materials. Total time: 6-10 hours over a weekend. Estimated annual savings: $200-500 in energy costs plus thousands in avoided emergency repairs. For tasks throughout the rest of the year, see our annual home maintenance schedule.