Your Boiler Won’t Work in a Power Cut. Here’s How to Stay Warm

It’s January, the lights go out, and a few minutes later you notice the radiators going cold. That’s the part most people don’t expect: almost every modern gas boiler needs electricity to run its pump, fan and controls. The gas is still on, but the heating isn’t.

Most power cuts in the UK are fixed within hours. But after a big storm, some homes can be without power for a day or more. Here’s how to keep everyone warm, safely, without spending a fortune.

The one rule: heat the person, not the house

You can’t heat a whole UK home without power, and you don’t need to. The goal is to keep yourself and your family warm. Everything below follows from that.

Step 1: Make one warm room

Pick one room where everyone lives, eats and sleeps until the power is back. The best choice is usually the smallest room with the fewest outside walls. A room that gets afternoon sun is a bonus.

• Close every internal door. Warm air escapes fast.
• Put a rolled towel or draught excluder along the bottom of the door.
• Open curtains on the sunny side during the day for free heat, then close all curtains as soon as it gets dark.
• Cover hard floors with rugs, blankets or even flattened cardboard. Cold floors pull heat out of your feet.

A few people in one small room genuinely warm it up. Every person gives off roughly as much heat as an old 100-watt light bulb.

Step 2: Layer properly

• Base layer: wool or synthetic thermals. Avoid cotton next to your skin, because it holds moisture and makes you colder.
• Middle layer: a fleece or thick jumper.
• Outer layer: even indoors, a gilet or coat helps.
• Extremities: a hat, thick socks and slippers. Fingerless gloves let you still use your phone.

Stay dry. Damp clothes pull heat away fast, so change out of them straight away.

Step 3: Heat your bed, not your bedroom

Nights are the hardest part.

• Put a blanket or rug under you as well as on top. Cold comes up through the mattress.
• A sleeping bag inside your duvet is a cheap upgrade that makes a big difference.
• Wear a hat and dry socks to bed.
• Use a hot water bottle filled with hot (not boiling) water, and check the bottle isn’t old or perished.

Step 4: Fuel yourself

Your body is the heater, and it needs fuel.

• Eat regularly, and have hot food and drinks when you can.
• Every time you boil water, fill a flask so it stays hot for hours.
• Move around. A few minutes of light exercise warms you faster than another blanket.
• Go easy on alcohol. It makes you feel warmer while you actually lose heat.

The danger section: carbon monoxide

Every winter, people are hurt in power cuts not by the cold but by carbon monoxide (CO). You can’t see it, smell it or taste it.

• Never use a BBQ or charcoal indoors, including in a garage or porch.
• Never run a generator indoors or in a garage or shed, even with the door open.
• Never use your gas oven or hob to heat a room.
• Never use a camping stove or patio heater as a room heater.

Fit a battery-powered carbon monoxide alarm. It keeps working in a power cut. Symptoms of CO poisoning include headache, dizziness, nausea, breathlessness and confusion. If you notice them, get into fresh air and call 999. If you smell gas, call the gas emergency line on 0800 111 999 (Northern Ireland: 0800 002 001). Read our full guide to carbon monoxide in power cuts.

Safer options for backup heat

• An open fire or wood burner, but only if you already have one and the chimney has been swept.
• A low-wattage electric blanket on a portable power station. Heated blankets use far less power than heaters, so a mid-size power station can run one for hours.
• Indoor-rated portable gas heaters do exist, but they must be specifically designed for indoor use, have an oxygen depletion sensor, and be used with ventilation and a CO alarm. If you’re not confident, skip it.

If in doubt, stick with layers, blankets and a warm room. That’s always safe.

UK extras most people miss

• Save 105 in your phone. It’s the free power cut number for England, Scotland and Wales. In Northern Ireland, call NIE Networks on 03457 643 643.
• Join the Priority Services Register if anyone at home is older, disabled, has a medical condition or a young child. It’s free and gets you extra help. See our Priority Services Register guide.
• Know where your stopcock is. In a long cold spell, pipes can freeze and burst.
• Check on neighbours, especially anyone older who lives alone.

For the full 72-hour basics, start with our Start Here checklist.