We all know by now that the world is only getting hotter.

Add that fact to the truth of the heatwave that’s breathing boiling hot air across most of the United States this summer, and I think everyone is stressing out about not only how to stay cool, but how to do it for cheaper.

And according to experts, the answer just might be the so-called “caveman method.”

Door and window expert Joseph Holman says that when it comes to keeping your home cool, you should “think of it like a cave.”

“A cave is cooler in heatwaves because it is dark and doesn’t have direct sunlight or a direct entrance for the heat. You want to probably mimic that.”

First of all, make sure all of your doors and windows are closed tight. The movement of air might give the illusion of being cool, but when a heatwave strikes, open doors and windows are just another way for heat to get inside.

“You want to reduce sunlight and stop the movement of the outside air inside. Even switching off the lights will help you with that.”

Keeping light-blocking drapes and blinds closed will also aid in keeping things cool, and there are even more permanent options if you’re into that.

“If you want to protect your home from the heat longer term, I would recommend investing in tinted film for windows to reflect the heat, as well as installing integral blinds as a smart way to control the temperature in your home.”

He adds that integral blinds will last longer, which offsets some of the cost.

Modern glass is also more reflective than older versions, and that roller blind canopies are also a good option for keeping direct sunlight from hitting your windows.

This is all really good advice, and the imagery is really helpful.

Simply stand in the middle of your house and ask yourself how you can turn it into a cave.

Done.

If you think that’s impressive, check out this story about a “goldmine” of lithium that was found in the U.S. that could completely change the EV battery game.