Open windows (at the right time)
It’s tempting to throw the windows open all day in the hope of a breeze, but when it is really hot outside, you only let in hotter air.
Open the windows nice and wide overnight (if it is safe to do so) or early in the morning to let cooler air in, then shut them as the outside temperature climbs.
Try to generate a through breeze by opening windows on opposite sides of your home or from top to bottom.
Close the curtains
A lot of heat comes through windows as thermal radiation, which warms the surfaces and air in a room, raising the ambient temperature.
Closing the curtains or blinds acts as a barrier, helping to prevent the heat from going further into your room beyond the window.
Keeping windows covered helps prevent thermal radiation from entering your room. Photograph: Oleksiy Boyko/Alamy
Cover windows from outside
If you can, hanging a sheet or other barrier over the outside of the window helps prevent thermal radiation from entering your room, which can keep it significantly cooler on very hot days.
There’s a reason homes in hot and sunny climes have shutters on the outside of their windows.
The British Blind & Shutter Association says research it commissioned at a London block of flats found that temperatures reached 47.5C in rooms without shading, whereas rooms that had external blinds fitted reached a maximum of 28C.
Get a fan …
Using an electric fan to move air around your home can help cool you, as long as the air temperature is less than 35C. It will not cool down a room.
Of course, fans come in various shapes and sizes, including pedestal, tower and desk versions, and with varying price tags.
This week the Guardian published an article that included our pick of the best fans. The best overall was named as the AirCraft Lume, a pedestal fan costing (at the time of writing) £119 from the online retailer AO. The one named as best budget fan and best desk fan is made by Devola and was available this week for £49.99.
Buying an energy-efficient model will help with running costs and reduce the amount of heat that the fan’s motor creates.
You can also position it in front of a window when it is cooler outside to encourage air to enter your home.
No fan of the heat? You could try blowing air over ice or bottles of frozen water to lower the temperature. Photograph: Tommaso Altamura/Alamy
… or an evaporative cooler
A step up from a standard fan is an evaporative cooler, which is essentially a fan that blows through a damp material. The water evaporates into the air, absorbing some of the heat energy and cooling the resulting breeze from the fan by a few degrees.
They work best in dry conditions, though, so can struggle in relatively humid British summers.
This week’s Guardian article on fans also looked at evaporative coolers, and the one our writer liked the best was the Swan 5 Litre Nordic Air Cooler (£69.99).
For a free version, you could – in theory – try pouring some cold water across a sealed, tiled floor, which will then evaporate to cool the tiles, though this could damage flooring material and will increase the humidity in your home.
Use a dehumidifier
Dehumidifiers are usually associated with the wet winter months, but one of the factors that makes heat less bearable is high humidity, because it reduces the body’s ability to cool itself effectively by sweating. A dry heat is much easier to deal with than a humid one.
If it is really humid in your home a dehumidifier can help keep you cool, though many generate their own heat as part of the process, so it is a balancing act.
DIY air conditioning
It won’t be nearly as effective as actual air conditioning, but to make a DIY air cooler, all you need to do is blow air over something cold. There are many YouTube videos showing different ways to create your own air conditioning surrogate, but the most basic is a bowl of ice water in front of a fan. Just be very careful with water and electricity.
Another popular technique is to use an old coolbox or polystyrene tub with a fan. Cut a hole in the top of the box big enough for a fan to blow into it, then cut an exhaust hole for the air to leave. Fill the box with ice packs or bottles of frozen water and let the fan blow straight down into the box over the bottles to pump colder air into the room.
Fire up the barbie? You could take your cooking outside. Photograph: Martin Godwin/The Guardian
Buy a portable air conditioner
Getting a proper “split” air conditioning system installed can be very expensive, but portable air conditioning units aren’t nearly as pricey. They are usually the size of a small filing cabinet and contain the compressor and the fan in one unit. They have the downside of generating heat in the place you are trying to cool, which has to be pumped through a tube and out of a window.
For short-term use in a heatwave, they can effectively cool one room, such as a bedroom or lounge. Cheap units cost from about £130, with good ones more in the £300 range. They consume a lot more electricity than a fan and are rated in British thermal units (BTU) for cooling power, so make sure you buy one powerful enough for the size of your room.
Turn things off and cook outside
When it’s very hot, turn off anything that generates heat.
Electrical appliances such as washing machines, dishwashers, TVs, stereos, games consoles and computers can all generate quite a lot of heat over time when in use, while other devices such as your router or lights also emit a little heat.
Cooking generates a lot of heat, so use the hob and oven sparingly and consider only cooking late at night when you can have the windows open.
Alternatively, take your cooking outside using a barbecue, camping stove or similar.
Lick a lolly: ice lollies can cool you down whatever your age. Photograph: Cultura Creative (RF)/Alamy
Eat cold food
Keeping yourself cool and hydrated can help you deal with heat.
Consider eating cold food such as sandwiches and salads or water-rich foods such as cucumbers and ice lollies.
Fill up bottles of water during the evening and store them in the fridge overnight so you have cold water to drink during the day.
Take cool showers
Taking a tepid but not freezing cold shower is an effective way of cooling your body. You want to cool the skin as much as possible without exposing it to very cold water, which can cause your blood vessels to contract, trapping the warm blood from radiating your core heat away through your skin.
As cool as Kvaratskhelia: a cold compress to the back of the neck – as enjoyed by PSG’s players this week at the Club World Cup – is particularly effective. Photograph: Mike Blake/Reuters
You can also use a cold compress to cool parts of your body – something that can be particularly effective on the back of your neck, your armpits or wrists.
If all else fails, take a trip to a place with air conditioning such as a shopping centre, supermarket, cinema or other cool space to recuperate.
Some say that checking into a cheap hotel with air conditioning can also be a lifeline in the hottest of nights.