As Britain braces for a potentially record-breaking heatwave, millions of people are looking for the best way to keep cool.
A powerful ‘heat dome’ settling over western Europe is expected to send temperatures soaring beyond June’s record of 35.6C today, with some forecasters predicting highs of up to 38C in parts of the UK.
With the tropical conditions set to continue this week, Britain’s hottest-ever temperature of 40.3C, set during the famous heatwave in 2022, could also be broken.
As health chiefs issue a ‘red alert’ weather warning – meaning there is a risk to life for citizens – there are important questions being asked: Should the blinds be closed during the day? Is it safe to sleep with an electric fan running? Would changing your bedsheets help you stay cooler at night?
There are health concerns, too: How much water should you really be drinking? Is there such a thing as drinking too much? And when it comes to cooling down, is a cold shower actually the best option?
With so much to consider, it can be difficult to know what is best to do. So, to find the most effective way to handle the heat, we asked experts for their top tips on staying comfortable and safe.
People shade from the sun under umbrellas on the River Cam, Cambridge
Keeping your home cool
Trying to keep your home at a comfortable temperature can be difficult, particularly if you are going to be in your workplace for much of the day and unable to control conditions as temperatures rise.
Dr Ben Roberts, senior lecturer in healthy buildings at Loughborough University, tells the Daily Mail: ‘Traditionally we’ve been a quite a cold country so we’ve been looking at keeping our houses warm in winter.
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‘It’s only since 2022 that we’ve had building regulations which have started to look at keeping our homes cool in summer. So, we’ve got a bit of catching up to do.
‘We see thousands of excess summer deaths, and those are deaths that wouldn’t have ordinarily happened had it not been for some kind of heatwave event. It is affecting people’s health and wellbeing, and at worst it’s killing people.’
This raises the question of whether blinds should be kept down, windows left open, and fans kept on.
But the answers can vary depending on the type of property you live in.
Top-floor flats, for example, tend to become hotter as heat rises, while homes with larger windows can also warm up rapidly in direct sunlight and shaded properties may be far cooler.
As a general rule of thumb, however, Dr Roberts advises that most people should always put their blinds down during the day.
He said: ‘If they are light in colour, or some kind of reflective metal, then it is worthwhile keeping your internal blinds or curtains closed during the day to stop the sun’s heat coming in because it will reflect some of that heat back out.’
For ventilation, the best approach is to open windows on opposite sides of a home during the coolest parts of the day, typically overnight or in the early morning, when temperatures are at their lowest.
Creating airflow through the home in this way allows cooler air to circulate more effectively than opening windows on just one side of the property.
Dr Roberts said: ‘Whenever it’s warmer outside than in, opening your windows just lets that hot air in. The general advice is that, during the peak of the day during heatwaves, it’s almost always that it’s going to be hotter outside than in – so that’s when you should be keeping your windows closed.
People seek shade, use umbrellas and fans, and spend time in parks
‘Then at night, when it’s likely to be cooler outside than in, that’s when you should open your windows if it’s safe to do so.
‘Obviously for a lot of people, especially if they’re living in ground floor flats or noisy polluted areas, there’s a variety of reasons why people might not want to open their windows. But the general advice is open your windows at night close them during the day during heatwaves.’
If a home has only one window, a fan positioned nearby can help move cooler outside air further into the room and improve flow throughout the property.
Leaving a fan on during the day, however, is not advised by experts.
Dr Roberts says: ‘There’s no benefit to having a fan on if you’re not in the home because all the fan is doing is it’s moving the air – it’s not changing the temperature of the air.
‘Unless you’re there to receive that air movement and feel that air movement across your skin, and to have that additional sweat evaporation that the fan creates, it’s doing nothing.’
How to dress
It’s often difficult to know what to wear when the temperatures rise, especially for those working in offices where formal dress codes are still expected.
While it may seem logical to wear as little clothing as possible, experts say loose, lightweight layers are often more effective at keeping the body cool than exposing more skin while wearing heavier fabrics.
Natural materials such as linen and cotton are among the best choices, as they allow air to circulate more freely and help the body control its temperature.
Traditional office attire can also be adapted by opting for lighter shirts and trousers made from breathable fabrics.
Loose-fitting clothing is generally recommended, as tighter garments can trap heat and restrict airflow.
Official guidance from the UKHSA also advises people to wear sunglasses and a hat when outdoors, particularly during the hottest part of the day, and to apply sunscreen regularly.
A wide-brimmed hat is considered especially effective, as it provides shade for the face, eyes and neck, helping to reduce exposure to direct sunlight.
A person uses an electric fan to cool down on the London Underground
Swimmers at Cullercoats Bay, North Tyneside, in the north east of England
What to do at bedtime
Trying to sleep during a heatwave is often one of the most frustrating parts of hot weather.
Tossing and turning, waking up drenched in sweat and feeling as though your bedroom has become a sauna, can make getting a good night’s rest seem impossible.
Fortunately, experts say there are several steps that can help improve sleep quality during the sizzling temperatures.
One of the easiest ways is to pay attention to bedding. Warm conditions cause the body to sweat more, while increased oil production and higher temperatures can encourage the growth of bacteria.
As a result, experts recommend washing and changing bedsheets more frequently during the summer months, ideally around once a week.
Heavy duvets should also be swapped for lighter alternatives where possible. Some people may even find they are more comfortable sleeping under a thin cotton sheet, with no duvet at all.
Fans can also help, though Dr Punam Krishan, an NHS GP, says many people do not fully understand how they work.
She says: ‘A fan doesn’t actually lower the temperature of a room. It works by moving air across your skin, helping sweat evaporate more efficiently and allowing your body to lose heat. During warm weather this can improve comfort and help some people feel cooler overnight although, in very extreme heat, a fan on its own may be less effective and additional cooling measures may be needed.
‘So, while methods such as opening windows and using electric fans to cool your room’s temperature are widely recognised, it’s important to also focus on cooling down your body. This is particularly essential for older adults who often sleep lighter and feel heat more acutely as the body’s temperature regulation becomes less efficient with age.’
People on a boat in Stratford-upon-Avon in Warwickshire on Monday June 22, 2026
Sun worshippers enjoy the weather on the River Cam in Cambridge, on Monday, June 22, 2026
Another way Dr Punam recommends to beat the heat is by taking a lukewarm shower rather than a cold one.
She says this can ‘work wonders’ because it draws warm blood away from the core and towards the skin, where it can cool in the air.
Dr Punam also advised keeping water by the bed because it can help prevent dehydration , while alcohol is best avoided as it can also contribute to dehydration.
Furthermore, once in bed, she says sleeping with wrists, ankles and neck outside of the covers can help to stay cool.
Don’t overdo the simple things
Certain groups are more vulnerable to the effects of extreme heat than others – and must take more care during the hottest days.
Those most at risk of serious complications from overheating include adults aged over 65, young children under five, people with long-term health conditions, particularly heart and breathing problems, pregnant women, and those who live alone, according to the UKHSA.
As temperatures rise, experts advise everyone – particularly those in higher-risk groups – to avoid unnecessary activities that could increase their body temperature or make overheating more likely.
That includes household chores such as cooking, cleaning and laundry, because ovens, hobs, tumble dryers and washing machines can generate significant amounts of heat and, in turn, raising temperatures.
Where possible, people are encouraged to choose lighter meals that require little or no cooking, such as salads, fruit and other cold foods.
It’s also key to recognise the warning signs of heat-related illness.
Symptoms of heat exhaustion can include dizziness, weakness, sweating, nausea, headaches, muscle cramps and clammy skin.
Signs of life-threatening heatstroke, meanwhile, can include confusion, nausea and loss of consciousness. A person may have very hot skin and a body temperature above 40C, but may stop sweating.
Anyone suspected of suffering from heatstroke should be treated as a medical emergency and emergency services should be contacted immediately.
A person drinks water at Parliament Square, central London, on Monday June 22, 2026
Stay hydrated
Becoming dehydrated is one of the biggest risks to human health during a heatwave because as temperatures rise, the body produces more sweat in an attempt to cool itself down.
While this is essential to keep the body functioning, it also causes the body to lose large amounts of fluid, increasing the risk of dehydration if not replenished.
Adults are typically advised to drink between six and eight glasses of fluid a day – roughly 1.5 to 2 litres.
However, experts believe people may need to increase their intake during periods of extreme heat, with up to three litres often recommended.
The NHS advises people to drink fluids regularly throughout the day when the weather is hot, even if they do not feel thirsty, and to opt for cold drinks where possible.
It is also advised that alcohol is avoided during hot weather, while caffeinated and hot drinks should be limited. As they are diuretics – meaning they take more fluid from the body – this can contribute to dehydration.
Dehydration can become serious if left untreated and, in extreme cases, can be fatal.
Common symptoms include feeling thirsty, headaches, dizziness or light-headedness, fatigue, a dry mouth, lips and tongue, and passing dark yellow or strong-smelling urine. People may also find they are urinating less often than usual.
More severe dehydration can cause confusion, sunken eyes, rapid breathing and a rapid heartbeat.
There are also dangers of having too much water – overhydration.
In some cases, excessive water intake can overwhelm the body’s ability to maintain the correct balance of electrolytes, particularly sodium, leading to a condition known as hyponatraemia.
When this happens, water flows through the body’s cells in an attempt to restore balance, causing them to swell, which can be dangerous and lead to symptoms including headaches, confusion, nausea, vomiting and, in severe cases, seizures or loss of consciousness.
Overhydration is most likely to occur when large amounts of water are consumed in a short period – causing the body to be overwhelmed.
Visiting air-conditioned and shaded facilities
For those struggling to keep cool at home, experts recommend spending time in air-conditioned or shaded public spaces during the hottest parts of the day.
While air conditioning remains relatively uncommon in many UK homes, it is found in places such as shopping centres, cinemas, libraries and museums.
Even a few hours spent in a cooler environment can help reduce the strain heat places on the body.
Public parks and green spaces can also provide relief from the heat, particularly areas with tree cover and plenty of shade.
