When the heating bill arrives, a plug-in heater and an electric blanket start to look like the sensible option. Used well, they are. Used with a worn flex, an overloaded extension lead or a blanket from the back of the airing cupboard, they are a leading everyday cause of home fires. This post covers electric heater fire safety UK households can sort in one evening.
Plug portable heaters straight into a wall socket, never leave them running unattended or while you sleep, keep them well clear of anything that can burn, and replace any electric blanket that is old, creased, scorched or has no thermostatic control. Most of these fires are preventable with checks that take minutes. None of it needs an electrician unless something looks damaged.
Why heaters and blankets are a problem
A typical portable heater draws a lot of current, commonly around 2 to 3kW, which is far more than a lamp or a phone charger. That puts continuous heavy load on the plug, socket and cable. Anything weak in that chain, such as a loose socket, a damaged flex or a cheap extension lead, heats up. That is where fires start.
Electric blankets are different. They run at low power but sit against bedding and are folded, creased and tucked for years, which damages the internal heating wires. Old blankets can overheat in a way you will not see until it is too late.
Safe heater habits
Where to plug it in
Use a wall socket, not an extension lead. If you must use a lead, choose a good-quality cable-unwound one, rated for the heater’s power, and fully unwind it. A coiled lead under heavy load heats up. Feel the plug and cable after an hour: warm is acceptable, hot or discoloured is a stop sign.
Where to put it
Keep it at least a metre from curtains, bedding, furniture and clothes.
Never dry washing on or over a heater.
Use it on a flat, hard surface, and never in a bathroom unless it is specifically rated for it.
Choose a model with a tip-over switch and overheat cut-out.
How long to run it
Turn it off when you leave the room and before bed. If you need warmth overnight, a thermostatic electric blanket or properly heated bedroom is safer than a running fan heater. Our guide to electric heating costs shows which options are cheaper to run for longer periods.
Electric blanket checks
My view: if you do not know how old your electric blanket is, replace it. A new one costs less than the fire. Electrical Safety First advises checking blankets regularly and replacing them after about ten years, and having them tested by a professional every few years.
Look for fraying, scorch marks, exposed wires, creases or stiff patches, and check the label shows the British Standard marking. Always follow the instructions on whether it is an underblanket, to be switched off before sleeping, or an overblanket, which is designed to be left on. Never use a blanket that is damp, and never fold it while it is warm.
Wider home fire safety
Heaters and blankets are one part of winter fire risk. The basic safety net is working smoke alarms on every floor, which is covered in our post on smoke alarm rules. Test them monthly and keep a clear escape route. For the wider picture of what you must and should do, see our guide to home safety rules in the UK.
Other winter electrical habits worth changing
Heaters are rarely the only load on a winter circuit. Tumble dryers, kettles and dehumidifiers all draw heavily. Avoid running several high-power appliances from the same socket or lead, and do not daisy-chain extension leads. If a plug top is warm every time you use an appliance, or a socket is scorched, stop using it. Fuse trips that happen repeatedly are a sign of overload or a fault, not an annoyance to reset and ignore.
Older homes with unmodernised wiring deserve extra care, because circuits were not designed for today’s mix of appliances. If your fuse board is old or you have not had an electrical inspection for years, it is worth booking one before winter.
Choosing a safer heater
If you are buying a new heater, look for a recognised UK safety mark, a thermostat, a timer and a tip-over cut-out. Oil-filled radiators and panel heaters with a fixed thermostat are generally easier to run safely than basic fan or bar heaters. Do not buy second-hand heaters with a worn flex, and recycle old ones properly rather than passing them on.
If you rent out a room or let a property
Landlords and anyone letting a room should note that portable heaters are one of the more common sources of complaint and risk in rented homes. Provide safe, fixed heating where you can, tell tenants or lodgers the basics in writing, and keep the safety certificates up to date. It is cheaper than an incident, and it makes insurance conversations simpler.
What to do in the next 30 minutes
Unplug every portable heater and inspect the flex and plug for damage or discolouration.
Move any heater that sits closer than a metre to curtains, bedding or furniture.
Take extension leads out of the heater circuit and plug heaters straight into wall sockets.
Check the age and condition of every electric blanket, and bin any you cannot date or that look worn.
Press the test button on each smoke alarm.
If you want a reminder before next winter, add to your Home+ checklist a yearly check of heaters, blankets and alarms, so it happens before the cold hits rather than after.
FAQ
Can I leave an electric heater on overnight? It is safest not to. If you need warmth in bed, use a thermostatic electric blanket that is designed for it, following the instructions, or heat the room beforehand.
Is it safe to use an extension lead with a heater? Plug straight into the wall wherever you can. If you must use a lead, use a good-quality, fully unwound one rated for the heater’s power.
How old is too old for an electric blanket? About ten years is a common limit, and sooner if it shows wear.
Can I leave an electric blanket on all night? Only if the label says it is designed for that, typically a thermostatically controlled overblanket. Switch off underblankets before sleeping.
What should I do if a plug or cable feels hot? Switch off and unplug it, and do not use it again until checked. A hot plug can mean a loose socket or damaged flex, so call an NICEIC-registered electrician if the socket itself is warm.
