As record heatwaves become the norm in the UK, the risk of fire and its associated dangers rises. So, how can you stop a blaze inside your home or in the garden when the heat is extreme?
We explain the risks of fires in hot weather and what you can do to prevent them.
EASY AS HACK
If you have a barbecue, keep water nearby and ensure the coals are extinguished before you go indoors.[1]
At a glance
- Experts expect wildfires to rise by 50% globally by 2100 [2]
- Higher temperatures put homes, businesses and people at risk
- Smouldering cigarettes, lithium batteries, mirrors, glass ornaments and vases in windows are some of the main culprits.
What causes a heatwave?
Experts say heatwaves are a steadily rising global threat caused by climate change. According to United Nations research, our impact on the climate means a 50% increase in extreme fires globally by the end of the century.[2]
As temperatures rise, heatwaves will become more frequent and severe.[3] The UK experienced two heatwaves in 2023, the second-warmest year on record. Dry weather led to wildfires in Wales, the Southwest and Yorkshire. It was the warmest June on record for the UK, with a 15.8C average beating the 14.9C seen in June 1940 and 1976 by 0.9C. In September, the UK saw the longest recorded run of consecutive days of high temperatures, exceeding 30C for seven days.[4]
THE IMPACT OF FIRES CAUSED BY HEATWAVES
Fires during hot weather pose a risk to lives, homes and livelihoods. You may have seen the devastation that grassfires caused in 2022 when temperatures topped 40 degrees Celsius.
A fire possibly started in a compost heap spread to dry fields and properties in Wennington, east London. The fire set fields ablaze and spread to the village, destroying around 20 homes and numerous vehicles. [3]
CAN HOT WEATHER CAUSE FIRES?
A heatwave doesn’t cause fires on its own, but they do create the perfect environment for them to start and spread. [17] Fires need an ignition source, such as open flames or static electricity, to start. [5] But we must also be aware of new or less obvious potential fire starters as our climate changes, such as glass, mirrors and electrical devices with lithium batteries overheating, or being left in the sun.
Fast-spreading wildfires and grassfires in parks, playgrounds, woodland, fields, and our gardens are some of the main risks of a fire breaking out during a heatwave. [6] The trigger can be natural (think lightning strike) or created by humans on purpose (arson) or through carelessness. [5]
COMMON CAUSES OF FIRE IN HEATWAVES
People are the most likely to cause fires during hot weather. Typical fire starters that we could avoid include the following:
- Neglected campfires
- Disposable barbecues
- Unattended garden bonfires
- Discarded cigarettes or matches
- Sunlight on mirrors or broken glass
- Glass vases on windowsills reflecting the sun
- Lithium batteries
HOW TO REDUCE THE RISK OF FIRE IN A HEATWAVE
Read our list of dos and don’ts to reduce the fire risk in your home and garden in a heatwave. Following these tips will help to keep you and other people safe, including the firefighters who battle wildfires and grassfires whenever the heat rises.
1. Check your home for fire hazards
Before a heatwave has started, it pays to check your home and any outbuildings for fire hazards.
- Test your fire, heat and smoke alarms to ensure they work.
- Dig out dead leaves in gutters
- Cut branches touching the property
- Store flammable substances such as car oil or pesticides out of direct sunlight
- Check exits aren’t blocked so you and your family can escape should the worst happen.[1]
All kinds of preventable risks can lead to a blaze. Other less common causes of house fires in the home include a build-up of crumbs in the toaster, overusing an extension cord, and leaving appliances on charge for too long.
2. Maintain your air conditioning
As the climate changes and heatwaves increase, aircon systems may become more popular in UK homes. Demand for them is steadily increasing with 213,0000 units sold in 2021 versus 154,000 in 2012, according to Statista. If you do get one, ensure you clean the a/c unit regularly to prevent dust from building up on the motors and sparking a fire. [7]
3. Move fire pits, chimineas and barbecues away from flammable objects
In the warmer weather, you may want to use heat sources like a chiminea, barbecue, fire pit or pizza oven in the slightly cooler evenings. Remember that branches, leaves, grass, and flammable objects like sheds, fences, wooden chairs, and tables will be dry. So, try to position the heat source on a flat surface away from these and cut back any foliage around immovable objects like a pizza oven. [] Keeping the grass short, vegetation controlled and plants away from buildings will help to reduce the risk of house fires. It’s best to have a bucket or tub of water or sand nearby in case you need to put a fire out.
Essential:
- Never leave fires unattended.
- Let any heat or cooking source cool down.
- Never refuel a barbecue while it remains hot.
- Avoid using flammable liquids on barbecues
- And always keep water and sand beside you in case you need to put out a fire.[8]
4. Avoid disposable barbecues in the countryside
Disposable barbecues left unattended or discarded in the countryside when still hot are a significant fire risk during a heatwave. They caused many wildfires in 2022. Only use them when you can reduce the risk, such as in the garden at home, on a beach or camp site. Keep the barbecue away from beach huts, tents and dry grass. Have water or sand nearby in case of emergency and ensure the barbecue is completely cool before moving it. [8] Never leave a disposable barbecue unattended – and avoid using them on a balcony where fire can spread fast.[6]
5. Keep electrical devices out of the sun
Overheating can affect technology and electrical items during a heatwave. Lithium batteries used in electric , such as e-scooters and e-bikes, mobile phones, rechargeable toys, tools and laptops are a specific fire risk. Keep them away from direct sunlight as the batteries contain flammable liquid that could cause a fire or explosion in high temperatures. [9] The charity Electrical Safety First recommends charging e-bikes and e-scooters during the day, away from exits, preferably outside and never in strong sunlight.[10]
6. Never cover a device you are charging
Mobile phones, hair straighteners and other small devices get hot when you charge them. When temperatures are high, it’s even more important to make sure you don’t cover them; as the heat can build up if they are under a blanket or pillow, potentially causing a fire.[7]
7. Don’t forget about cigarettes and matches
Someone throws a cigarette out of a car window or a match smouldering in a wastepaper bin. Remember that these can easily set dry grass or other rubbish alight in a heatwave. Make sure cigarettes and matches are completely put out.[6]
8. Don’t throw rubbish away carelessly
The sun can magnify the glass in discarded bottles and start a fire. Accumulated rubbish can help it to spread. So, reduce the fire risk by taking your rubbish with you and throwing it away safely. [6]
9. Remove mirrors and glass objects from the garden and windowsills
Remove any reflective objects to prevent fires in the garden or your balcony: mirrors on walls and tables, crystal balls and suncatchers, a pair of glasses left on a cushion. Direct sunlight reflecting off them can cause fires. [11]
10. Be careful with candles
The risk of lighting candles in the garden or your home is more significant during a heatwave when a warm gust of wind could spark a blaze and its surroundings are tinderbox dry. Try keeping them in a lantern to protect them from the wind or position them away from fire hazards like wood and dry grass. Be careful not to leave them unattended. Consider using flameless candles with batteries while the weather is hot.
11. Smoke Detectors and Fire extinguishers
Ensure you have smoke and heat alarms installed in your home and remember to regularly check they are working correctly. You can also buy small fire extinguishers in case of an emergency.
Read our tips on staying safe and avoiding house fires.
PROTECT YOUR HOME FROM HIGH TEMPERATURES
A heatwave’s extreme temperatures can damage your home. Here are some measures to prevent the heat from affecting it, especially if you’re in a top floor flat, or you have a loft conversion.
Roof leaks
UV rays and extreme heat from above and the heat from the house below can cause roof damage, leading to leaks.
Action
Installing an attic fan in your loft space can reduce the heat build-up, to help keep you and the roof cooler. [12] Adding a protective UV coating can also help to lessen the sun’s impact, as well as improve energy efficiency.[14] Avoid doing roof repairs yourself to avoid accidents, it’s best to get tradesman to help with any roof maintenance. [14]
Window heat
Windows let in sunlight that increases internal heat and bleaches your soft furnishings and pictures.
Action
Try blinds or sunscreens on your windows to reduce internal heat or film to protect them. [12] You may also be able to use plants or bushes to provide shade over windows to help block the sun’s rays.
Cladding damage
High temperatures can expand external wooden cladding like weatherboarding while humidity lets in moisture, causing the wood and paint to deteriorate.[15]
Action
Your best action is to check the cladding regularly, adding filler and heat-resistant paint when needed. [16] You could also replace the wood with alternatives like fibre cement weatherboarding that’s resistant to fire. [16]
Find out more about keeping your home cool on our Heat Hub.
Sources
[1] https://www.redcross.org.uk/get-help/prepare-for-emergencies/heatwaves-uk/wildfires
[2] https://www.unep.org/news-and-stories/press-release/number-wildfires-rise-50-2100-and-governments-are-not-prepared
[3] https://nationalemergenciestrust.org.uk/wildfires-growing-risk/
[4] https://www.carbonbrief.org/met-office-a-review-of-the-uks-climate-in-2023/
[5] https://www.bbc.co.uk/news/newsbeat-41608281
[6] https://www.london-fire.gov.uk/news/2022-news/june/brigade-issues-safety-advice-over-uk-heatwave
[7] https://metro.co.uk/2022/07/19/how-to-avoid-potential-house-fires-during-a-heatwave-17026490/#:~:text=Regularly%20remov
[8] https://www.rbfrs.co.uk/latest-news/2022/important-heatwave-advice/
[9] https://www.unsw.edu.au/newsroom/news/2023/03/seven-things-you-need-to-know-about-lithium-ion-battery-safety
[10] https://www.electricalsafetyfirst.org.uk/battery-breakdown/safer-use/
[11] https://www.yourharlow.com/2024/01/28/sunlight-reflecting-off-a-crystal-ball-ornament-caused-a-fire-prompting-a-warning-from-fire-services/
[12] https://claddingcoatings.co.uk/news/5-essential-steps-to-protect-your-building-from-heat-damage/
[13]UV Protection Window Film to Reduce UV Rays
[14] https://www.roof-crafters.com/learn/shining-light-uv-protected-roofs-long-lasting-investment#:~:text=UV%20protection%20can%20be%20added,than%20your%20afternoon%20beach%20escapade
[15] https://www.hunker.com/13774520/how-extreme-heat-damages-your-house
[16] https://www.designingbuildings.co.uk/Weatherboarding
[17] Heatwave: Does hot weather cause fires?
