How to Winterize Your Home and Cut Heating Bills This Winter

Winterizing a house comes down to three jobs: stop warm air from leaking out, make your heating system run efficiently, and protect the plumbing from freezing. This guide walks through each job in the order that pays back fastest, with what it costs, what you can do yourself this weekend, and where to find help if money is tight.

Start With a 30-Minute Draft Hunt

Before you buy a single tube of caulk, find out where your house is actually losing heat. Guessing leads people to spend $600 on new curtains when the real problem is an unsealed attic hatch.

Pick a cold, windy day. Close every window and exterior door, turn off the furnace, and switch on every exhaust fan you have: bathroom fans, the range hood, even the clothes dryer on air-only. That pulls air out of the house and draws outside air in through every gap. Now walk the house with a lit incense stick or a damp hand and check these spots:

• Around window sashes and where window frames meet the wall
• Along the bottom and hinge side of exterior doors
• Electrical outlets and switch plates on exterior walls
• Where pipes, cables, and dryer vents pass through walls
• The attic hatch or pull-down stairs
• Baseboards and the joint where the floor meets exterior walls
• Recessed ceiling lights on the top floor
• The fireplace, if the damper is old or doesn’t close tight

Mark every leak with painter’s tape. Most homes end up with 15 to 30 pieces of tape, and that list becomes your shopping list.

If you want hard numbers, many utilities offer discounted or free home energy audits with a blower-door test, which measures exactly how leaky the house is. Call your gas or electric provider and ask. It’s worth doing before any big-ticket insulation job.

Seal the Leaks: The Cheapest Heating Upgrade You Can Buy

According to ENERGY STAR, air sealing combined with adding insulation in attics, floors over crawl spaces, and basements saves homeowners an average of 15% on heating and cooling costs, or about 11% on total energy costs. The sealing part is the cheap part.

Windows

Use a paintable acrylic-latex caulk on interior trim gaps and a silicone or polyurethane caulk outside where the frame meets siding. Scrape out cracked old caulk first; new caulk over old rarely bonds. For drafty single-pane or older double-hung windows you don’t plan to replace, a shrink-film window insulation kit (the kind you tape on and tighten with a hair dryer) is inexpensive and surprisingly effective for one season.

Doors

Close the door on a dollar bill. If it slides out with no drag, the weatherstripping is shot. Replace worn foam or V-strip weatherstripping on the jambs and add or adjust the door sweep at the bottom. Many modern thresholds have adjustment screws that raise the threshold to meet the sweep, a five-minute fix most people never know exists.

Outlets, Plumbing, and Attic Openings

• Outlets and switches: Foam gaskets go behind the cover plate. Turn off the breaker first.
• Pipe and wire penetrations: Gaps under 1/4 inch get caulk; bigger gaps get low-expansion spray foam.
• Attic hatch: Glue rigid foam board to the top of the hatch and weatherstrip the edge it sits on. Pull-down stairs can get a zippered insulated cover.
• Recessed lights: Only seal around fixtures rated IC (insulation contact) and airtight. Older non-IC cans can overheat if covered; that’s a job for an electrician.

Two safety notes. Don’t seal around chimneys or furnace flues with regular foam or caulk; those need fire-rated sealant and sheet metal. And if you tighten up an older house with gas appliances, make sure you have working carbon monoxide alarms on every level, which Ready.gov recommends for every home anyway.

Add Insulation Where It Counts

Once the air leaks are sealed, insulation is the next biggest lever, and the attic is almost always the first place to look. Heat rises, so an under-insulated attic is where much of your furnace output goes.

Go into the attic with a tape measure. If you can see the tops of the ceiling joists, you probably don’t have enough. Many older homes have only a few inches of settled fiberglass. Adding loose-fill or batt insulation on top of what’s there is a common DIY project, and home improvement stores often lend a blowing machine free with a minimum purchase of loose-fill bags.

Other spots to check:

• Rim joists in the basement: The wooden band sitting on top of the foundation wall is a major leak point. Cut rigid foam to fit each bay and seal the edges with spray foam.
• Floors over crawl spaces or unheated garages: Batts between floor joists stop the cold-floor feeling in rooms above.
• Heating ducts in unheated spaces: Seal joints with mastic or foil tape (not cloth duct tape, which fails), then wrap the ducts in insulation.

Seal before you insulate. Insulation slows heat moving through a surface, but it doesn’t stop air. Laying new batts over unsealed gaps is like putting on a sweater with the zipper open.

Tune Up Your Furnace, Boiler, or Heat Pump

A heating system that’s been neglected burns more fuel for the same warmth. Book a professional tune-up in early fall, before technicians get slammed by the first cold snap. A good tune-up includes checking burners or heat strips, testing safety controls, inspecting the heat exchanger for cracks on gas furnaces, and measuring airflow.

Between visits, the most important homeowner task is the filter. ENERGY STAR’s maintenance guidance is to check the filter every month and, at a minimum, change it every three months. A clogged filter restricts airflow and makes the blower work harder.

Other quick checks:

• Vacuum supply and return vents, and move furniture or rugs that block them.
• Bleed hot-water radiators so trapped air doesn’t leave cold spots at the top.
• For heat pumps, clear leaves and snow from around the outdoor unit and keep 2 feet of clearance.
• Replace carbon monoxide alarm batteries and test smoke alarms.

Set Your Thermostat to Work While You Sleep

The U.S. Department of Energy estimates you can save as much as 10% a year on heating and cooling by turning your thermostat back 7 to 10 degrees Fahrenheit for 8 hours a day from its normal setting. For most families, that means dropping the temperature overnight and while everyone is at work or school.

A practical schedule for a household that leaves by 8 a.m. looks like this:

Time	Setting	Why
6:00 a.m. – 8:00 a.m.	68°F	Comfortable while getting ready
8:00 a.m. – 5:00 p.m.	60–62°F	Nobody home; the setback is where savings happen
5:00 p.m. – 10:00 p.m.	68°F	Evening at home
10:00 p.m. – 6:00 a.m.	61–63°F	Sleeping under blankets

Two caveats. First, if you have a heat pump, avoid deep setbacks unless your thermostat is designed for heat pumps; a big temperature jump can trigger the expensive electric backup strips. Smaller setbacks of 2 to 4 degrees, or a heat-pump-aware smart thermostat, work better. Second, the myth that “the furnace works harder to reheat the house, so you don’t save anything” is false. A cooler house loses heat more slowly, so a setback always uses less energy overall.

Two free tricks: switch ceiling fans to clockwise at low speed to push warm air down from the ceiling, and open south-facing curtains on sunny days, then close all curtains at dusk.

Protect Your Pipes and Plumbing

A burst pipe can do more damage in one night than a year of high heating bills. Water expands when it freezes, and the pressure buildup, often in the section between the ice and a closed faucet, is what splits the pipe.

Before the First Freeze

1. Disconnect and drain garden hoses. A hose left on can trap water in the spigot.
2. Shut off the interior valve that feeds outdoor spigots (if you have one), then open the outside faucet to drain it. Frost-free spigots still need the hose removed.
3. Blow out or drain your lawn irrigation system, following the manufacturer’s instructions or hiring a pro.
4. Insulate exposed pipes in the garage, crawl space, basement, and under-sink cabinets on exterior walls with foam pipe sleeves.
5. Find your main water shutoff and make sure it turns. Tag it so anyone in the house can find it in an emergency.

During a Cold Snap

The American Red Cross recommends opening kitchen and bathroom cabinet doors so warm air reaches the plumbing, letting cold water drip from faucets served by exposed pipes, and keeping the thermostat at the same temperature day and night during extreme cold. If you’re traveling, leave the heat on and set it no lower than 55°F.

If you turn on a faucet and only a trickle comes out, suspect a frozen pipe. Keep the faucet open and apply heat with a hair dryer, heating pad, or space heater kept at a safe distance. Never use an open flame. If you can’t find or reach the frozen section, call a plumber.

Check the Outside of the House

Winterizing isn’t only an inside job. Water and ice outside cause some of the most expensive winter repairs.

• Gutters: Clean them after the leaves drop. Clogged gutters overflow, and in freezing weather that water can form ice dams at the roof edge that push meltwater under shingles.
• Downspouts: Extend them at least a few feet from the foundation.
• Roof: From the ground with binoculars, look for missing or lifted shingles and damaged flashing around chimneys and vents.
• Chimney: If you burn wood, schedule a chimney sweep and inspection before the season.
• Trees: Trim branches that overhang the roof or power lines; ice-loaded limbs snap.
• Exterior caulk: Recaulk gaps around windows, doors, and where siding meets trim.

What Winterizing Costs, and Where to Find Help

Here’s a realistic breakdown of common projects. Prices vary by region, house size, and store, so treat these as typical DIY material ranges rather than quotes.

Project	Typical DIY Cost	Difficulty	Payback
Caulk and weatherstripping for a whole house	$50–$150	Easy	Usually one season
Outlet gaskets and door sweeps	$20–$60	Easy	One season
Window shrink film (several windows)	$20–$50	Easy	One season
Foam pipe insulation	$15–$50	Easy	Prevents burst-pipe damage
Programmable or smart thermostat	$30–$250	Moderate	Often 1–2 years
DIY blown attic insulation	$400–$1,200	Moderate	Several years
Professional furnace tune-up	Varies by market	Pro	Efficiency plus fewer breakdowns

The pattern is clear: the cheapest jobs pay back fastest. Do the $100 sealing work before you price new windows.

Help With Heating Costs and Upgrades in 2026

One important change for 2026: the federal Energy Efficient Home Improvement Credit (Section 25C), which covered part of the cost of insulation, windows, doors, and heat pumps, was terminated by the tax law signed in July 2025. The IRS lists the credit as available only for qualifying property placed in service through the end of 2025. If you finished a project in 2025, you can still claim it on your 2025 return, but don’t count on it for new work in 2026. Tax rules change, so confirm with the IRS or a tax professional.

Where to look instead:

• Your utility: Many gas and electric companies offer rebates for insulation, smart thermostats, and heat pumps, plus discounted energy audits.
• Your state energy office: Some states run their own rebate programs; availability and funding vary.
• LIHEAP: The Low Income Home Energy Assistance Program helps eligible households pay heating bills and, in some states, cover weatherization and furnace repairs.
• Weatherization Assistance Program: The Department of Energy’s program provides free weatherization for eligible low-income households, and the agency reports average savings of $372 or more per year for participating homes.

Frequently Asked Questions

When should I winterize my home?

Aim for early to mid-fall, before overnight temperatures regularly drop below freezing. Caulk cures poorly in cold weather (check the minimum application temperature on the tube), and HVAC technicians book up fast once the first cold snap hits.

What temperature should I set my thermostat to in winter?

Around 68°F while you’re home and awake is a common target. Lower it 7 to 10 degrees while you sleep or are away; the Department of Energy estimates that can save up to 10% a year. Heat pump owners should use smaller setbacks unless their thermostat is designed for heat pumps.

Is it worth replacing old windows to save on heating?

Usually not as a first step. Window replacement is expensive and takes many years to pay back through energy savings alone. Sealing, weatherstripping, storm windows, or shrink film get you much of the comfort benefit for a fraction of the cost. Replace windows when they’re failing, not just to save energy.

How do I keep pipes from freezing when I’m away?

Keep the heat on at no lower than 55°F, open cabinet doors under sinks on exterior walls, and consider shutting off the main water valve and draining the lines if you’ll be gone for a long stretch. A smart leak or temperature sensor can alert your phone if something goes wrong.

Can renters winterize an apartment?

Yes. Removable options like window shrink film, draft stoppers for doors, outlet gaskets, thermal curtains, and adjusting the thermostat schedule are all renter-friendly. For bigger issues like broken weatherstripping or a failing furnace, put a repair request to your landlord in writing.

Is the federal energy tax credit still available in 2026?

The Section 25C credit ended for qualifying property placed in service after December 31, 2025. Check with your utility and state energy office for rebates, and confirm current rules on IRS.gov, since tax law can change.

Your Weekend Winterizing Plan

If you only have one weekend, do this: run the draft hunt, spend under $100 on caulk, weatherstripping, door sweeps, and outlet gaskets, change the furnace filter, program the thermostat, and drain the outdoor spigots. That covers the fastest-payback work and the biggest risk (frozen pipes). Then book a furnace tune-up and look into attic insulation and utility rebates before the coldest months arrive.