Fire safety in a garage with a classic car

Old cars catch fire for the same reasons as new ones, but they have more of the causes and fewer of the safeguards.

Wiring

Insulation hardens and cracks with age, connections corrode, and previous owners add accessories with whatever wire was to hand. Many older cars also have little fuse protection: specialist technical notes say many British sports cars of the 1950s and 1960s had only two fuses, leaving circuits such as the headlamps unfused. A short on an unfused circuit can heat a wire until its insulation burns. Rodents add to the risk: Hagerty UK warns that mice gnawing old wiring can cause short circuits and dashboard fires (see mice and rats).

Have unknown wiring checked, and ask a specialist about adding in-line fuses to unprotected circuits. Hagerty UK also advises checking that fuses are the correct rating: one that is too big protects nothing.

Fuel leaks

Hagerty UK says one of the most common sources of engine bay fires is a perished petrol hose leaking fuel onto something hot. Rubber hose ages, and the FBHVC warns that rubber exposed to petrol containing ethanol can swell and soften, then shrink and crack as it dries, causing fuel leaks. Check hoses and clips each year, and treat any smell of petrol in the garage as a fault to find, not the normal smell of an old car.

Batteries and chargers

Hagerty UK warns that a badly secured battery can tip, short against metal and start a fire. Charging a lead-acid battery also gives off hydrogen. The HSE says that hydrogen and oxygen are produced inside a battery while it charges, especially as it nears full charge, and that the mixture is ideal for an explosion if a spark or flame reaches it. Many battery explosions happen while leads are being connected or disconnected.

Other electrical equipment

Dehumidifiers, heaters, compressors and freezers all add load and heat. Hertfordshire Fire and Rescue Service advises keeping portable heaters at least one metre from anything that can burn, on a flat, stable surface, and not leaving them running in an empty room. Do not use paraffin or bottled gas heaters in a garage with a car in it: they add water vapour as well as fire and carbon monoxide risks (see damp and condensation).

Extension leads

A cable reel left partly wound can overheat. Dorset & Wiltshire Fire and Rescue Service advises always unwinding reels fully, even for a short run. Council fire safety guidance adds: do not overload a lead beyond its rating (typically 13 amps, or 3,000 watts, in total) and do not plug one extension lead into another. A dehumidifier that runs all winter is better on a fixed socket.

The simplest way to remove the battery as a source of fire is to disconnect it. A battery isolator switch, fitted in the main battery lead, does the same job with a turn of a key and also stops small drains from clocks and radios. If you fit one, have it rated for the starter current and mounted securely.

When disconnecting, the HSE advises removing the earthed terminal first, and refitting it last when you reconnect. Remember that many British cars built before the mid 1960s are positive earth, as Hagerty UK points out, and some have since been converted, so check which terminal is earthed on your car before you start. The winter lay-up guide covers whether to use a conditioner or disconnect over winter.

If you leave a charger connected through the winter:

• Use a charger designed to be left connected. The RAC advises checking that your charger can be left on a battery indefinitely. Smart chargers and battery conditioners monitor the battery and adjust their charge. The HSE warns that continuing to charge a battery once it is fully charged produces a lot of gas.
• Ventilate. The RAC says to charge in a well-ventilated, dry place, because charging can release a flammable gas. The HSE advises keeping hydrogen well below its explosive limit by ventilation, with air entering low and leaving high.
• Avoid sparks at the battery. Switch the charger off at the mains before connecting or disconnecting the clips, unless the maker's instructions say otherwise, as the HSE advises.
• Place it safely. Stand the charger on a firm, non-flammable surface where it cannot fall, get wet or be covered, not on upholstery, cardboard or rags.
• Check it on each visit for a swollen, hot or smelly battery and damaged leads.

Petrol vapour is heavier than air, as Merseyside Fire and Rescue Service points out. The HSE says it does not disperse easily, tends to sink to the lowest level and may travel long distances, and that there is always a risk of fire or explosion if a source of ignition is present. Keep as little as you can.

The HSE's guidance under the Petroleum (Consolidation) Regulations 2014 for homes and other non-workplace premises is:

Suitable containers, in the HSE's guidance, are:

• Plastic containers of up to 10 litres each;
• Metal containers of up to 20 litres each;
• a demountable fuel tank of up to 30 litres.

Petrol must not be stored in living accommodation. Petrol in a car's own tank does not count towards the total. The HSE also says petrol stored indoors needs a direct exit to the open air, with ventilation to that exit, and that it must be kept away from sources of ignition and heat, and must not be dispensed (pumped from a tank) where it is stored. If you intend to store more than 30 litres, read the HSE's guidance in full: there are further conditions, including on the fire resistance of a garage attached to a house. Never fill, drain or decant petrol inside a closed garage.

A smoke alarm in a garage is likely to be set off by exhaust fumes: Greater Manchester Fire and Rescue Service says heat alarms suit rooms where steam, fumes or moisture could cause nuisance alarms. Cornwall Fire and Rescue Service warns never to disconnect an alarm or take its batteries out if it goes off by mistake. A heat alarm responds to a rise in temperature and ignores smoke and fumes.

Cornwall Fire and Rescue Service lists heat alarms as the right type for kitchens and garages, and the National Fire Chiefs Council (NFCC) recommends heat alarms rather than smoke alarms in garages where e-bikes or e-scooters are stored or charged. Linked alarms all sound when one of them detects a fire, as Cornwall Fire and Rescue Service explains; in Scotland, interlinked alarms have been required in all homes since February 2022. A garage heat alarm linked to the house alarms means a fire at night is heard where people sleep. Test alarms regularly: Greater Manchester Fire and Rescue Service says at least once a month, and the Scottish Fire and Rescue Service says every week.

Fire services are clear that the first priority is to get out. Devon & Somerset Fire and Rescue Service advises that if a fire starts you should get out, stay out and call 999, and Derbyshire Fire and Rescue Service says to tackle only small fires in their early stages, after making sure everyone is out and your escape route is clear. If in doubt, do not tackle it.

If you keep an extinguisher in the garage, it must suit the likely fires: solids such as trim and tyres (class A), flammable liquids such as petrol and oil (class B), and electrical equipment. Fire services' guidance on vehicle fires names dry powder or foam extinguishers made to BS EN 3, and never water on an engine fire, because it can short wiring and spread burning petrol.

Buy one made to BS EN 3 with independent certification such as the Kitemark or the British Approvals for Fire Equipment (BAFE) mark, keep it by the door, check its pressure gauge regularly and have it serviced regularly; Devon & Somerset Fire and Rescue Service warns that extinguishers can explode if they have not been maintained properly. Hagerty UK also advises carrying one in the car.

A fire blanket puts out a small fire by smothering it. Fire services recommend them mainly for kitchens, and Surrey Fire and Rescue Service says not to use one on a large fire. In a garage, one may deal with a small fire on a bench, but not a car fire. Look for one made to BS EN 1869.

Cloths soaked in linseed oil, and in some other oils, can heat up as the oil reacts with air. If the heat cannot escape, a heap of rags can catch fire on its own, hours later. Northamptonshire Fire and Rescue Service advises:

• do not keep oil-soaked cloths indoors;
• hang them outside to dry, so moving air carries the heat away;
• or soak them in water, seal them in a plastic bag and put them in the household bin;
• if you must keep them, use an airtight container, preferably metal.

Many garage fires start during work on the car. Gloucestershire Fire and Rescue Service advises never using welding equipment near fuel tanks or fuel lines. Before welding or grinding:

• strip out interior trim from near the work, including hidden sound deadening and rust-prevention wax, as Classics World advises;
• move petrol, tyres, rags and solvents well away from sparks;
• never weld or cut a tank or drum that has held petrol or another flammable liquid;
• have an extinguisher within reach, and keep checking the area for an hour after you stop. Hot-work guidance for builders from the Scottish Fire and Rescue Service says to inspect frequently for the first 30 minutes after the work ends and again 30 minutes later, to make sure nothing is smouldering.

E-bikes, e-scooters and tool batteries are often charged in garages. They can catch fire very quickly if their batteries are damaged or failing, and London Fire Brigade described e-bikes in 2023 as the capital's fastest-growing fire trend. The NFCC advises:

• use the manufacturer's charger, and unplug it when charging is finished;
• charge while you are awake and in, not overnight or while you are out;
• do not cover chargers or battery packs, and keep them away from anything that burns easily;
• fit heat alarms in garages where batteries are charged or stored.

Keep e-bikes and spare batteries away from the classic car, and away from the garage door if that is your way out. If a lithium battery catches fire, do not try to put it out: get out and call 999.

If an electric car shares the garage or driveway, charge it from a dedicated charge point installed by a registered electrician. Electrical Safety First, the electrical safety charity, says a dedicated charge point is far safer than charging from a wall socket, and warns against joining extension leads together. Never charge an electric car from the lead that feeds the dehumidifier and conditioner.

Read your policy schedule, not just the summary. Some classic policies restrict cover overnight unless the car is in a locked garage: one insurer's policy summary excludes loss or damage between 10pm and 6am within 500 metres of your address unless the car is in a secure locked garage. Read any endorsements on your schedule too. If you store petrol, have a workshop in the garage or add equipment such as a welder or a car lift, tell your home and car insurers. See storing a classic car for laid-up cover.

1. Get everyone out, closing the garage door and any door to the house behind you if it is safe. A closed door slows a fire.
2. Call 999 and ask for the fire service. Tell them about the car, petrol, gas cylinders or lithium batteries in the garage.
3. Do not go back in for the car or anything else.
4. Only tackle a very small fire if your exit is behind you and you have the right extinguisher. If it does not go out quickly, leave.
5. Do not open the bonnet if the engine bay is on fire. Fire services advise releasing the catch but not lifting the bonnet, and aiming an extinguisher through the grille or under the edge.
6. Do not use water on a petrol or electrical fire.

If the car catches fire on the road, the same services advise pulling over, switching off, releasing the bonnet catch without opening the bonnet, getting everyone out and well away, calling 999 and warning other traffic.

Our winter lay-up guide and printable checklist include the battery and fuel steps in order, and the main storage guide covers everything else.