Passive or Active Ventilation. The idea is to encourage air to pass through the home, which helps with removing heat from inside. Passive Ventilation would be opening windows, using wind catchers, etc. This depends on the design of your home, among other things that you probably don't really have control over. Active ventilation is the same idea, but you use strategically placed fans to induce good airflow. For example, if you have two windows that are opposite to each other, you can place a fan at one window to intake air, and a fan at the other window as exhaust.
this post was submitted on 27 Jun 2025
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When its hot, avoid cooking indoors if you can. Especially iff you dont have proper exhaust in your kitchen. Buy some food that require less heat or none. Sandwiches, Fruits, Salads, etc.
Keep your home cool and yourself too.
My method is "live in Alaska."
Live somewhere it doesn't get hot.
If your roof is not shaded by trees, a light colored roof makes a huge difference. This can be accomplished a number of ways. Replacing your roofing material with a lighter color is ideal but expensive. Coating it with something like Henry Tropi-cool is durable but the product is also a little pricey. The absolute budget way to do this on an asphalt shingled roof is with a slurry of masonry lime. I've experimented with all of these methods and the results are dramatic. In my case the coating paid for itself within one season and made the house noticeably more comfortable.
Open upstairs windows after 8-9 PM to let cool air in, blackout blinds work really well too
This works really well. I also open the downstairs windows. The hot air going up and out creates a draft effect, sucking in cold air from the downstairs windows.
Not really a thing you can just do, but thick walls. I live in an old house with double layered exterior brick walls. It has such a massive impact that sometimes I wear a vest inside, while it's heatstroke temperatures outside.
Pretty good (but long) answer with historic solutions here : https://solar.lowtechmagazine.com/2025/06/dressing-and-undressing-the-home/
My short answer : do not let the sunshine in (stores, awnings, shutters), let it flow let it go (air), I like big walls and I cannot lie
Came here to point to this.
Also, if outside noise is preventing one from keeping the windows open over night, get custom-fitted silicone earplugs.
Probably not exactly the answer you're looking for.
If you have access to sun and are tech savvy, hop on Facebook market place or equivalent. You can probably get very cheap used solar panels that still have plenty of output. Rig up a AC unit in one room and cool just it.
Surprised this hasn't been mentioned yet, but awnings. Glass is a superb thermal conductor. Not even the best curtain in the world would prevent air getting hot through the window if the sun is hitting it directly. An awning is meant to shade the window glass, preventing heating way more than a curtain alone.
Also, if the home has several levels, open the upper floor windows more than the lower ones. Hot air expands and raises. If it has somewhere to escape it will keep the house cool and the windows will draw in wind. Wind moves faster at higher altitudes. That's why attic fans are so effective.
Sleep outside, if you have a space. Get a deck umbrella, a mosquito net and a cot and a sleeping bag (actually on super hot days I used to just sleep on a towel). It's so much cooler than trying to get by indoors with no AC, even with fans. And it's rather pleasant.
Close on the sunny side during the day. If the air on the shadow side is cooler, less humid or same as inside, open that side. If your home is more humid or hot than the sunny side, close it just enough to prevent sun ray for entering.
If the heat is not also damp, put wet clothes next to windows or fan for natural refreshment. You can also spray water on your curtain.
Wear natural fiber, coton or lint. Loose clothes, that does cover you body. This way, the evaporation of sweat cools you down. You will also smell much less than if you are wearing synthetic fibers.
Wash your feet, your face, your forarm with water regularly. Do not use cold water, room-temperature or fresh is better but go all the way to the articulation (ankle, elbow), wash inside and outside and let the water dry on you.
Drink small amount of water regularly. Once again not cold.
Keet your heat cover when you expose yourself to the sun. When you get home change out of your clothes that were heated by the sun.
Do not over exercice.
I was also wondering if plants could also help inside, any ideas ?
They shouldn't. Plants can raise humidity, but they have no power to break the the laws of thermodynamics. Once heat is in your house you can only really move it out of your house; there is no destroying it in place. Note this does not apply to plants just on the outside of your home, like on a roof.
Watch your use of appliances carefully. Even a fridge generates heat - it might be better to place it outdoors or semi-outdoors if you're going to be really hardcore about your approach.
A better insulated house will keep heat out as well as cold, so all usual tips on building or renovating your envelope apply.
Curtains are a god send. Make sure you have them to isolate things coming into and out of your house. So have a curtain to isolate your entry way. That way the heat stays there. Same things at the stairs so you can keep the cool in the baseline while you stay there
Also to note that depending on your house and the outside temp its not worthwhile to open the windows at night. But generally it is better. Make sure you have a fan in the window blowing the hot air out as well. Its best if its upstairs to draw the cool air in.
Sorry about the content in spanish, but some years ago there were news about someone placing agave or some succulents/cacti in people's roofs, since some species "absorb" the heat, something along those lines.
Here https://youtu.be/BOjYB7qaESE
Also this plant seems to help refreshing the room in general
https://wikipedia.org/wiki/Dracaena_trifasciata
I haven't tested them yet since I am just growing my little garden on the roof of my house, but hope something of that helps.
Pretty much anything on a roof will cool you down. The soil which will contain water is slower to heat while the plants will be be absorbing solar energy and "perspiring" to cool you down.
Locations under large trees can be locally up to 10 degrees colder in the summer and 10 degrees warmer in the winter.
Years ago I was watching Doomsday Preppers and one fella dug a long trench, 100 foot if I'm not mistaken.
In the trench he laid a large PVC pipe and filled in the trench. At the far end of the pipe there was an air inlet. He ran the pipe into his basement and up inside a wall with an inline fan. Cool air, as well as fresh air.
Didn't do anything for the humidity, I suspect.
He claimed it worked, I can not confirm.
It does make since as it's about 4c/39f four feet/1.2m underground.
So DIY ground source heating/cooling, basically.
I suspect that's not long and deep enough, but if it is, it will produce air at the local year-round average temperature, at all times. (Whatever that happens to be)
Thats basically how earthships are cooled. You can also run the pipe through an evaporative cooler to cool the air even more.
You can also run the pipe through an evaporative cooler to cool the air even more.
At some point there, you've just reinvented AC.
Only if you use a better working fluid and add compression and expansion steps, but a long pipe in a ditch filled with water isn't what I would call AC quite yet.
Aren't there AC systems that just evapourate water from municipal supplies to the atmosphere?
I mean, yes, I'd agree that blowing air over a standing water body isn't AC, but we're getting close.
You're thinking of a swamp cooler. In some places they work great, in other places they're next to useless.
Air conditioners are called that because they "condition" the air by not just cooling but also by reducing the humidity.
I think on a purely technical note, Air Conditioning goes beyond just cooling the air and involves reduction of humidity. Personally, I wouldn't consider it AC because you'd have to keep refilling the evaporator resivor, instead of just powering the device, but that is a nitpicky item that isn't technically a requirement.
I put foil insulation on some of my bigger windows in the summer. Especially southern facing windows (in northern hemisphere). That mixed with tons of fans and the occasional cold towel when needed helps tremendously.
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