How to hold heat in your home when the furnace stops: insulate, close off rooms, cover windows, and never use ovens or grills for warmth.
- Pick one small interior room, close it off and stay together.
- Cover windows and door gaps; dress in dry layers and a hat.
- Never use ovens, grills, camp stoves or generators indoors for heat.
When power fails in winter, the clock starts on your home's heat. A well sealed house can hold useful warmth for hours, and with a few smart moves you can stretch that time. The aim is simple: keep the heat you have, shrink the space you need to warm, and keep everyone dressed for the cold.
Act early, before the house cools
The best time to prepare is at the first sign of an outage. Heat is easier to keep than to regain.
- If you still have heat, do not turn the thermostat up high just before the cut, but make sure the house is comfortably warm.
- Close all curtains and blinds after dark. In the daytime, open south facing ones to let sunlight in, then close them again as the sun goes down.
- Keep doors and windows shut. Avoid going in and out more than you must.
- Put on layers right away instead of waiting until you are cold.
Shrink the space you heat
Choose one interior room, ideally with few or small windows, and make it your warm room. Bedrooms, bathrooms or a small den work well. Then:
- Close doors to rooms you will not use.
- Block door gaps with rolled towels or blankets.
- Hang a blanket or sheet over the doorway if the door is missing.
- Bring mattresses, sleeping bags and blankets into this room.
- Keep everyone, including pets, together so body heat helps.
See also our general guide, how to stay warm without power.
Windows, floors and drafts
Windows lose a lot of heat. Cover them with heavy curtains, blankets, towels or even cardboard pushed against the glass. If you have time and tape, plastic sheeting over a window adds a layer of still air. Check the base of exterior doors and stuff a towel or rolled blanket against the gap. Rugs or cushions on bare floors help too, since cold floors pull warmth from your feet.
Wear a hat indoors, wool or thermal socks, and several thin layers rather than one thick one. Keep clothing dry. If anything gets damp, change it. Winter plans in colder regions are covered in the winter storm prep checklist.
What never to use for heat
This is the most important rule on this page. Each winter, people are harmed by trying to heat a home with equipment meant for outdoors. If you want a backup heat source, choose one that is designed for indoor use and follow the maker's instructions, and install working carbon monoxide alarms with fresh batteries. Read carbon monoxide safety in a power outage before using any fuel burning device. Our heat and light hub collects safer gear options.
Protect pipes and watch for warning signs
If the house will get very cold, pipes can freeze. Open cabinet doors under sinks to let room air reach pipes. If the outage is long and the house is going below freezing, ask local authorities or a plumber about draining the system, and note where your main water shutoff is. Check on older adults, babies and anyone who cannot warm themselves, because cold affects them faster. Signs of hypothermia include shivering that will not stop, confusion, drowsiness and slurred speech. If you see these, call emergency services and warm the person gradually.
When to leave
If indoor temperatures keep falling and you cannot stay safe, go to a warming centre, a friend's home or another place with heat. Plan your route before roads worsen, and keep your car fuel above half in winter. A car kit helps if you get stuck; see winter car emergency kit.
Heat loss is slow when you act early. Cover windows, close off rooms, gather in one place and keep dressed warmly.
Quick answers
How long will my house stay warm?
It depends on insulation, outdoor temperature, wind and house size. A tight house loses heat more slowly, but plan to move to a single room.
Can I use my oven to warm the kitchen?
No. Gas and other ovens are not designed for heating and can release carbon monoxide. Use blankets, layers and a small warm room instead.