This is unironically how they cooled homes before AC: ice and fans.

So much good advice here already, so I'm just going to send solidarity to you in dealing with this, it's so taxing and pretty scary.

Last summer I did a cold shower at the end of the day just to be able to sleep. We are lucky enough to also be able to go stand in a lake until the core temp drops. Many here are advicing against this, but my middle aged perimeno body really did better with sleep after standing in a cool shower long enough for my core temp to drop to where the shower no longer felt cool. Ended up with a terrible water bill and a bad conscience with the water comsumption, but sleep is important and data centers use a billion showers worth of water for no good reason.

I also like to eat cool things, like watermelon slices frozen or cold soups.

I read somewhere that there is a way to diy paint windowds with white chalk for effective cooling, but the various coverings in this thread are probably more accessible.

I also read a tip somewhere on just putting a cool water bottle or something in your crotch, this will cool you down very well apparently (if you can tolerate it).

Edit. Adding that with the shower also never dry yourself, but just let evaporation do the work, it cools you so well. I like to go stand in front of the fan naked if it's very hot, it's pretty nice and helps you sleep. Sleep fully naked and with no insulation on you, I do a cotton bedsheet only because I can't sleep fully exposed for some reason. I've also gone to sleep on the floor, because it's lower and all the cushioning in a bed gets very hot when it's already hot.

The problem with the Soviet block building I live in is that the thick conrete walls start to accumulate heat after a few hot days and it's impossible to get anything to cool after a point. None of these have AC.

lots of good tips in here. something i would do when i felt like all my tricks weren't cutting it was to put on swimming stuff and then take a cool shower, but not dry off very much. then id lay in some shady spot under / near a fan. even with higher humidity, that can be very cooling in the short term. i set up a hammock on a porch with a fan and would just do that repeatedly to get through the hottest parts of the hottest days.

cool water running over your back, neck, pits, groin cools your body temp quickly.

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other, less drastic: shade trees pull heat from their surroundings with evapotranspiration. si the effect of shade plus being a heat sink. it can be significant with lots of trees. parks a good idea to visit. leaving the city can be good, as they tend to create a heat dome from the lack of plants and all the buildings just absorbing heat, activity creating heat, etc.

don't expose your skin to the sun any more than you must. cover your head or stick to the shade. the sun cooks your ass. wear light color/light weight fabrics that are baggy and allow breezes. breezes save your ass.

mid day siesta. don't gotta sleep, but do not be active. hottest parts of the days tend to be late afternoon. have a plan.

if you can find a way to be cooler at night, sleep is way easier and you will be more rested/less prone to heat exhaustion/heat injury.

Everyone here is mentioning fans, which is completely true. Try to vent the house so that the air moves up & out, bring the cooler air in at night, close up the windows & use blinds / reflectors during the day.

What I wanted to add though, is you. Wear lighter & looser clothing. Take your socks & shoes off. Cut your hair shorter. Sleep on top of the sheets, and take a mid-day siesta if you can.

Just because your home doesn't have A/C doesn't mean no one does. Common trick in the USA is to go see an afternoon movie or walk around an indoor mall. Heck, I can remember going and riding the subway around for 3 hours one summer just to get out of the heat. Not familiar with UK, but I bet there's similar available if you look.

my tip is to open the windows and the doors and wear light weight clothes. we sweat and thats a huge advantage. its not just the heat to be wary about but heatstroke/sunstroke and sunburn. cover your head with a hat. apply sun screen if you stay out in the sun even indoors. drink water and high water content fruits and veggies like cucumbers, watermelon and yogurt. keep ice in the freezer. dont take cold showers because they can be uncomfortable. instead take showers with normal temperature and rinse with cold water at the end. its not just physical but also psychological. its important to vent and complain, isolation makes it harder to bear.

if you have a freezer, freeze plastic bottle of water and hold it for couple of minutes during the day (the bottle would sweat though, so be mindful where you put it) when you feel hot (hands are very quick heat transfer device, and most comfortable with different temperature, feet also work, so if you are sitting you can put legs on top of it and sort of roll it around), if it’s uncomfy you can use cooled bottle, but it heats up much quicker *(forgot to mention, single t-shirt will insulate frozen bottle enough to not be uncomfy). also you can fall sleep with cooled bottle neat legs or face, but thats depending on how much you move around.

it freezes in around 2 hours so you can juggle two bottles (don’t fill it fully leave small air bubbl for ice expansion). probably fancy ice packs work better but eh

If you are out somewhere and need to cool down, running cold water over your wrists is a quick and easy way to cool down.

Putting a wet towel on your head is also an easy way to have evaporative cooling.

Aussie here, didn't have aircon till recently.

• Open house at night, doors if you can (i.e. it's safe), get a cross breeze going. Ceiling fans or range hoods that vent outside or in roof space can help pull air through.

• Close the house at the arse end of dawn. Draw curtains over windows facing the sun. Shading them outside is ideal, or pinning reflective mylar over them on the outside.

• Stay hydrated. You want to sweat, and you need water.

• wet your body where arteries run near the surface, front sides of neck, back of the skull, groin, armpits.

• Sweat needs airflow. Dress in light natural fabric, use fans. Even fanning yourself with a lid can make a huge difference.

• Keep the sun off ya. Hat, long light sleeves, long light pants. Think about how desert peoples dress. Naked is fine inside lol.

• Cold showers are nice.

• The elites don't want you to know this but you can put your pajamas or bedsheets in the freezer. Ice packs in bed are nice too. You can drop the temp (but raise humidity) with a fine mist of water from a spraybottle.

• You're allowed to sleep outdoors if you have the room.

• Sleeping on the floor will be cooler than a raised bed.

• if out and about parasols (or large umbrellas) are awesome for shading you

From someone who lives in Wuhan (one of the original Three Furnaces of China) as well as Australia:

• Spicy food in a ventilated area. Works in Chongqing, works in India, works in Wuhan, works in Thailand, works in Mexico, etc etc. Spicy food causes sweat (without actually increasing your body temperature any more than eating the exact same food without the spice). This will cool your body down so long as there's even a mild breeze. Note: This won't make you feel cooler, at least not initially, but the sweat drawing heat from your body will reduce your temperature and help avoid things like heat stroke.

• Drink loads of water. Room temperature is counterintuitively better than iced water.

• Cool showers. Not cold, you might get your body confused and think you're freezing and start retaining heat.

• Air dry after. Supposedly this is actually better for your skin but that's not why we're doing this. As the water evaporates, it will take heat with it.

• Eating iced cream or other frozen things in excess can also trigger that response.

• Expose your belly. I'm not sure if this actually works or is just a Chinese unc tactic. Cigarette optional

• Peat bogs. Just go and submerge yourself in a peat bog, like the Britons of old before the Romans arrived. Alternatively just a bathtub filled with room temperature water could do the trick, if you don't have a peat bog handy.

• Unironically try and get a shirt cricket players wear. Long sleeve, white coloured and breathable. Loose polyester or polyester/cotton blends. Try and avoid wearing standard polyester, that shit isn't nearly as breathable.

• While we're on the topic, try and get cotton weaves that aren't intended to retain heat, but breathe. Linen is probably the best choice, but linen is a pain in the ass to iron. Bamboo does alright. Obviously avoid wool. Shirts with large logos/prints on them will also block ventilation, so try and avoid wearing those.

• A spray bottle of water in front of a fan does wonders. Seriously, just have the fan pointed at you and spray your face or body.

Grew up in Florida, our AC broke for at least a week almost every summer.

Most of the tips here are good, especially opening the windows at night with fans pointed out to create a cross breeze, pulling fresh cooler air through the house.

Tip for quick relief, put damp washcloths in the freezer. Apply frosty rag to your forehead and neck. Replace when warm. I would sometimes just spend the peak of the day laying down with cold rags waiting for it to cool down.

Similarly, just hold onto an ice pack. You have a lot of blood vessels in your hands, and any sort of reusable freezer pack can pull a surprising amount of body heat out through your hands.

Using fewer rooms and closing the doors to the unused ones can increase the effectiveness of the cooling methods discussed here. Also true for heating in winter.

hey comradde... i know u...

Haven't tried it, but a science trick I heard was putting something reflective like tinfoil on the outside part of the windows so that no radiation is entering the house and getting trapped by the insulation. It might look funny but it sounds promising

I've seen multiple sources recommend that you open your windows at night and run fans to bring the cool night air into your house. Then close your windows during the day so that the cool air stays trapped in your house. As someone from the US, I'd worry about wildlife flying into the window, especially bats. Maybe your windows have mesh window screens.

Today, London is 33C during the day but only 20C at night.

Avoid using appliances that generate excessive amounts of heat like an oven or gaming pc. Use these appliances at night if needed.

Having large trees near your house could help shade the house from sunlight.

Avoid physical activity and excessive labor.

Maybe you could have a designated cold room your house? If there is one room in your home that is cooler than others, you could spend more time in that room. Probably want to avoid being near the refrigerator as it produces heat. If you have a basement it might be cooler under ground level.

If things are really bad, you could try sleeping during the day and being awake during the night. I'm not a doctor, so I shouldn't really tell people when to sleep. I like being awake during the night because it's quieter and cooler.

Go to public spaces during the day time which have air conditioning. Perhaps a grocery store or a coffee shop.

Buy an air conditioning unit. Things are only going to get worse. Maybe just get a window unit if you don't have resource.

If covering your windows makes it worse your home is heating up from a different source, primarily. Should investigate what that is. If it's outside your control you need an AC.

Take showers to cool yourself. It'll force evaporation on you and cool you a bit directly. Don't take super cold showers, that can make your body respond as if you're in icy weather and heat you up.

I think the best thing that you can really do without having more resources is stuff like evaporative/swamp coolers (which only work at certain relative humidities, but they might work for you. Basically evaporation cools everything the same way your sweat cools you. But if sweat isn't cooling you bc humidity, they don't work either) or things like putting frozen bottles/etc in front of fans, cool water sprayed as a mist, etc

I wish I had better advice but I don't. Wet bulb events terrify me. I wish we could get you at least a portable air conditioner, but Iirc you still need donations for a washing machine and I just know everybody's resources are very limited :/

fans, preferably ceiling fans but desk fans and standing fans also work. for ceiling fans make sure the fan is spinning the correct way. for desk fans you can do a poor man's version of water AC and put a thin damp rag (not dripping otherwise the water might damage the fan) on the cage so it blows the air through the rag. it probably only works in dry climates though.

if your building doesn't trap heat well, open the windows and doors to have air circulation but have your curtains closed to minimise the amount of light entering the building.

Fans

What helps me is cognitively reframing it as a vacation. Get one of those 20€ ice cube boxes that come with two trays to easily make full sized ice cubes. I bought two of those, so now I can fill the box with 400 ice cubes each day, for plenty of iced coffee and cold water for my cats.

Fans seem to get a bad rap by people used to AC ("They just blow hot air in your face!") but I don't really get the hangup. On hot days I mount a little clip on fan outside on my balcony pointed at me and I feel it helps a lot with staying cool, even at 40°C.

I guess I just try to enjoy the heat, rather than doing my best to fight it. Sure it gets uncomfy but you also get to enjoy lots of showers, homemade lemonade and spicy bean burritos. Wear flip flops, pretend you're in Mexico or what have you.