Stay Cool Sleeping in a Car [16 Vehicle-Dweller Pro Tips]

Stay Cool Sleeping in a Car [16 Vehicle-Dweller Pro Tips]
Want to beat the heat, and stay cool sleeping in a car? Use these 16 pro tips!

I’ve lived full-time in a Toyota Prius for the past 13 months. And I can tell you that one of the most CHALLENGING issues is how to stay cool sleeping in a car.

Good news for you…I’m going to share a bunch of really helpful tips to keep you cool no matter how warm the weather is!

Whether your car’s ac isn’t working, or maybe you just don’t want to waste money on fuel by leaving the engine running 24/7, I’ve got you covered.

Let’s get to it…

Don’t Run the Air Conditioning 24/7 to Stay Cool When Living in Your Car!

I put this first for a reason. If you’re going to be car camping on a regular basis - or living in a vehicle full-time - surviving on a tight budget is going to be vital.

And nothing will drain your pockets faster than the air conditioning running in your car all day & night.

While you may be tempted during warm weather and hot summers, you must avoid this practice at all costs.

Instead, follow the top tips below to stay cool while sleeping, or whenever you’re in your or night.

Tip #1: Park in the Shade

Doing just this one easy thing can keep your car cool in even the most scorching of summer heat.

Under a big tree is the best spot to be when it’s really hot. Also, next to large buildings that throw off a lot of shade. And parking garages that are located in malls, casinos, hospitals and convention centers are awesome options, too.

Believe it or not, when you park in a shaded area, the temperature difference can be 15-20 degrees cooler versus parking in direct sunlight. That’s a huge difference on an 80+ or 90+ degree day!

Of course, at night you don’t have to worry about the sun, but if you work in your vehicle during the day like many nomads do, or maybe you like sleeping in the car during the daytime hours, then you absolutely must follow this advice.

Tip #2: Crack the Windows

While this may seem like common sense, I’ve actually seen a lot of nomads overlook this - especially at night.

Maybe they’re worried about theft or a break-in, getting rain inside the car, or some other valid reason. But not cracking the windows prevents ventilation and airflow from entering the car.

Unless you have the air conditioner on, always leave your car windows cracked on both driver & passengers sides, even just 2” or 3”. This will keep the cabin air moving around, which will help you fall asleep easier.

Try attaching rain guards to your car doors, like the ones below. They are a great way to keep moisture out while still leaving the windows slightly open.

Tip #3: Eat Cold, Lighter Foods

Not sure about you, but the last thing I like to do in hot weather is eat a lot of hot, heavy food. Especially before bedtime.

Avoid this if you can, as it will greatly defeat trying to beat the heat.

Things like mashed potatoes, hearty soups, heavy pasta dishes, hot hoagies and similar foods should not be consumed when the heat is high, as they will raise your core body temperature.

Instead, opt for cold, lighter fare, such as; salads, fruits & veggies, trail mix, yogurt, cheese, canned tuna, etc.

Interestingly, spicy foods can both make you hot AND help cool you off. Your body temp will rise after first eating them, but you’ll likely soon start perspiring or sweating heavily, which in turn will help chill you down.

So try noshing on something spicy, or not…this one’s up to you!

Tip #4: Take a Cold Shower Before Turning In

A cold shower before hitting the sack is not only refreshing, but it will help you sleep in your car better on warm summer evenings.

For added benefit, don't fully dry your hair. Leave it damp, and you'll feel crisp and invigorated.

Tip #5: Crack Open the Sunroof

If no bad weather is expected, opening up the sunroof is a fantastic way to stay cool when sleeping in a vehicle.

They even sell magnetic mesh sunroof covers online, that allow you to leave the sunroof open without inviting mosquitos and other bugs into the car!

Tip #6: Add Sunshades and/or Insulate Your Windows

Did you know that the inside of a hot car on a summer’s day can reach temperatures exceeding 130 degrees!

That’s not only mind-blowing, it’s also highly dangerous if you’ll be working, sleeping or lounging in your vehicle during the daytime hours.

With temps like this, you must beat the heat at all costs. That’s where sunshades come in. They are lifesavers for nomads!

You can make these yourself or buy them, but they are MANDATORY items for vehicle-dwellers, and one of the best ways to stay cool.

I couldn’t imagine living without window covers in my car. They’re not only excellent for providing privacy, but they also drop the temperature significantly during the daytime.

Want to make a set of cheap sunshades? Maybe buy a set? Check out my post: Car Camping Window Covers [How to Make & Where to Buy]

Tip #7: Use a USB or Battery-Powered Fan

Most nomads don’t have big fancy campers, nor do we stay at a campsite often. So we have to conserve what little energy we have since we can’t connect to electrical hook-ups. Usually, we get our power from battery banks or portable power stations.

Fortunately, they sell a ginormous amount of battery-powered fans nowadays, and you can easily run these on any of the options I mentioned above.

Not only does a fan provide excellent air flow, it also creates a soothing breeze in your sleeping space, which leads to a better nightly snooze.

Luno USB-Powered Car Camping Fan

Check Amazon’s Price

Amacool Battery-Powered Camping Fan

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Tip #8: Tint Your Windows

This one is a bit tricky, since each U.S. state has differing rules when it comes to tinted car windows. You need to find out first what the laws are where you are primarily based out of, and then go from there. However…

Most states do allow some form of tinting, though the exact amount and what windows obviously varies.

Bottom line, if you want to keep cool during the daytime hours in your car, having tints will drastically help reduce the heat that enters your vehicle.

Tip #9: Wear a Damp T-Shirt to Bed

One of the most simple tips for sleeping in a hot car is wearing a cold, damp t-shirt to bed…and it works like a charm!

Just douse your t-shirt with the iciest water shortly before bedtime, and then ring it out so that the shirt is slightly damp.

Doing just this alone will help drop your body heat a lot. Couple this with opening your car windows or with using  a small fan, and you’ll feel totally refreshed throughout the night.

Tip #10: Use a Cooling Sleeping Pad

This tip is great for car campers, nomads, or anyone else who lives in a vehicle during the warmer months.

While a cooling sleep pad won’t reduce the air temperature in your car, it WILL provide cozy cushioning and a nice body chill, due to its gel infused properties.

For nights when it’s not too too hot, or maybe for those who don’t like air blowing on them while they sleep, a pad like this would be perfect.

Cool Care Cooling Sleep Pad

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Tip #11: Open Your Vents Up

Did you know that a car’s air vents can still bring fresh air into a vehicle even if the climate control is off? Yes, they can!

It amazes me that many people don’t realize this. They think just because the air conditioner or heater is turned off that the car is completely sealed, and no air is being circulated. Now you know.

So make sure your vents are fully open, and point them towards you when you’re sleeping. Every little trick helps when it comes to escaping the heat, and this one is important.

Tip #12: Use Proper Bedding

Another super way to cool your body down while sleeping is to only use cotton, linen or bamboo sheets. These are made from natural fibers, which are much more breathable.

Avoid fleece, polyester and acrylic sheets like the plague if you get hot easily, or when the weather is very warm.

On the same note, consider an air mattress instead of one made of foam, as the former is WAY better when it comes to staying cool because there is less material to retain heat.

Tip #13: Avoid Sleeping Bags

I totally get it. Sleeping bags make you feel cradled, homey, and snug as a bug. But you must ditch yours when the hotter months arrive!

This should really be common sense, but I see many of my fellow nomads using these even during periods of extreme heat. Which is kind of like stuffing yourself in a burrito of warm air all night.

If you’re sleeping in your car during times of higher temps, try using just a sheet, or only wearing your undergarments when turning in for the night.

Maybe even go full commando!

Tip #14: Sleep with Water Bottles or Nalgene Bottles

Just like people sleep with hot water bottles to keep warm during the winter, you can do the opposite in the summer!

Simply fill up a couple of empty water bottles, a Nalgene bottle, or even a hot water bottle with the coldest H2O that you can, and place them beside you before going to sleep at night. You can even put one or two directly on your body.

The method behind this madness is easy…the bottles will act as ‘ice packs’ that help reduce your body temperature and provide a refreshing chill.

Tip #15: Drink Lots of Cold Fluids

Hydrate, hydrate, hydrate!

Drink LOTS of fluids when the temps are scorching. While any fluids will do, water is obviously the best, and it's the cheapest and healthiest, too.

Try drinking fluids as cold as you can tolerate, since they will help drop your core body temperature, which in turn will take the edge off the heat.

Tip #16: Blast the AC Before Bed

Sometimes the heat and humidity are so bad that you desperately need a blast of cold air to make your car comfortable.

If this is the case, run the air conditioning on high for 20-30 minutes before bedtime. Doing so will eliminate any warm, stale air in the interior of a car, and will help keep your body cool.

Questions & Answers

When is it Too Hot to Sleep in Car?

This is a difficult question to answer, as each person has a different tolerance for hot weather. Coupled with other factors, there is no definitive set temperature threshold.

If you’re being sensible and following these tips, making it through a hot 100 degree night is more than doable, though it may not be the most comfortable. Of course…

If you’re going to try sleeping in a car during the day when it’s 90+ with the windows up and no sunshades, then you’re asking for trouble.

Practice common sense at all times and be aware of your limits. And if you need to, crank the ac up in the car. Spending a few bucks on gasoline to run the vehicle for the night for comfort is better than risking heatstroke.

Do Portable Car Air Conditioners Work? What About Arctic Air?

There are a slew of these mini ac units being sold online, and they have become wildly popular over the last few years. Arctic Air is probably the most famous, though there are a zillion copycats. In short, save your money, because they mostly don’t work.

I say “mostly” since they can bring some relief from the heat, but very very little, and it’s highly location dependent.

These devices are basically evaporative coolers (also called swamp coolers in the south), and they operate by blowing lukewarm air over a tank of cold water. This will surely provide some cooling effects, however, there are many drawbacks, such as…

*When the cold water warms up (usually within a few minutes on very hot days), these units will just be blowing mild air out.

*Due to the size of these devices (very tiny), you would literally have to be directly in front of them within a few inches to feel anything.

*Evaporative coolers only work well in NON-humid environments.

*Having to add cold water to the tank of these devices many times per day isn’t realistic or manageable.

Imagine a fan blowing on you when it’s 95 degrees with sky high humidity. And you’re holding a big chunk of ice in front of it. As the fan blows hot air over the cold ice, the air will be chilled, and it’ll make you feel colder.

This is the same EXACT way that evaporative coolers operate. As I said though…

Due to the reasons I mentioned above, they are terribly ineffective in 99% of situations.

Don’t waste a nickel of your money on these contraptions. Follow the tips I’ve laid out in this article and you’ll be more than fine.

Can a Roof-Top Car Tent Help in Keeping Cool?

A lot of nomads enjoy tent camping from time-to-time, and some even keep a tent mounted to the top of their vehicle that they use on a regular basis.

As we all know, hot air rises, and one would think that spending the night in a tent that’s higher than a car would lead to a hotter night’s sleep, but this isn’t the case.

A difference of a few feet - laying inside a car versus on top of one - isn’t going to change the temperature by much...if at all.

Matter of fact, it is probably easier to stay cool in a roof-top tent since a larger amount of air will make its way inside versus through the hard walls of a vehicle.

Final Thoughts

Dealing with extreme weather - hot or cold - when living and sleeping in a car can be tough.

But if there's one thing I've learned from my time on the road, it's this...

There's usually a fix to whatever problem just have to find the solution.

I've provided you with 16 solutions that all work. I know because I've tried them all, and still do. But...

Don't make the mistake of trying just 1 or 2 of these. The real "trick" to beating the heat is to practice as many of these as you can at once. When done together, they all add up and help bring relief.

Finally, don't write these tips off because they are simple. Oftentimes, the best solution for a problem is the simplest. These are usually the most effective, too.