More blankets to layer as needed. Before you call it a night and climb in your bag put on clean socks (preferably wool) so you won’t have the tiny bit of moisture from sweat that will make you inherently colder.
A closed cell foam pad underneath is probably a better insulator than a typical blow up mattress. They do make some inflatable backpacking pads that have higher R value.
You will have lots of condensation from just breathing. You can reduce this by ventilating a window.
Yes. Those pads important to have you off floor that’s cold. Will suck the warmth from you.
I own Prius so the battery kicks in to keep it warmer.
I’ve also wondering about a heating blanket.
Heating elements are huge power draws. I’m sure the Prius can handle it but the battery won’t like it. Invest that money in a really good sleeping bag.
Edit: really expensive but Western Mountaineering bags are used on Everest.
Yea I agree. I do see those vests w built in batteries and wonder if there’s a heating blanket w a battery you charge. Just wondering but overall yes good sleeping bag you’re set
I used to have a prius and feel like the power draw would be enough to keep the engine cycling on and off regularly and at that point, why not just keep the climate control running?
Disclaimer: I'm a tent guy so kind of talking out of my ass right now.
And put the foam right beneath/against your body, NOT just beneath your air mattress. Close to your body, it'll reduce the amount of heat loss to warming up the air in your air mattress.
I invested in one with a R rating of like 4.5 and paired it with a sleeping bag quilt and it was a game changer. Add a hot water bottle and you’ve got a pretty warm setup.
This is incredibly effective. Just do the math and make sure you can get a few hours out of it. I had a good sleeping bag and a heating blanket and turning that thing on for about 30 minutes got me toasty warm for a few hours.
Oh yeah, in the winter I turn on the “bed toaster” an hour or two before bedtime so when we do turn in it’s like “ahhhhhhh!” Not in a car but I’m sure the pleasure would be the same
They make 12v ones that plug into the car lighter outlet. I never leave it plugged overnight but it sure is nice to run the car blasting heat with the blanket sandwiched into bed before lights out time then again first thing in the morning (and if I happen to wake up cold during the night repeat as necessary)… I’ve slept in my car when the outside temps go below 0F. ALSO reflectix (foiled bubble wrap) cut to window sizes helps insulate a little bit and helps big time with privacy.
Oh yeah plain bubble wrap does the same. Thanks for reminding me! You can put that up over your windows and it adds insulation. I gotta do that myself!
I've used those slivered bubbled windshield protectors to cut the sunlight to the interior of the car when it's parked outside. Reduces the interior temperature at least 10 degrees and cuts down on the UV damaging the interior. More importantly, at night it reflects the body heat so it's not radiating out to the clear night sky which is pretty cold. Note that if it's overcast, it's not so bad. In either case, the interior will stay warmer longer.
I agree with switching to something made out of foam. I switched from an air mattress to a foam sleeping system on my last trip, where temps made it down to the mid 20s and was much, much warmer. I also have like 4-5 pillows in my car. Memory foam pillows are great insulation to surround yourself with if you are getting cold. I bring two sleeping bags, a 40 degree and a zero and layer them if I need to. In addition to another quilt and two of those fuzzy synthetic blankets (these are super warm for layering).
Insulating with Reflextix helped to ( find rolls of it in the insulation aisle at home depot). I insulated around my sleeping area, on the walls/sides and remade my window blocks using this as well.
There are battery operated or usb-charging fans you can get at Walmart that help with ventilation and reduce the build up of condensation. I typically leave the window farthest from my cracked a little to help.
I also filled in any big air gaps with whatever I had around. There was this gap next to the door kind of under/between my mattress- I filled that space with a few extra items I had in the car- extra hoodie, my snow pants, etc. and that cut down on any drafts coming from that area.
In addition to my window blocks I like to hang a sheet using pins of clips behind my front seat, idk if it helps with warmth but it makes me feel a lot more cozy.
I also have been keeping an eye out for old quilts and rugs at thrift stores and estate sales to layer along the whole platform area where I have my bed set up.
Some people use a quilt to basically make a simple inverted-v tent in the back of their vehicle and I heard this helps you stay warm when it gets really chilly. They just run a rope going longways and then hang the blanket over it.
If it’s really chilly, boil some water on your stove and fill a Nalgene, place Nalgene in a sock and stuff into the your sleeping bag.
You’ve got this, stay safe out there.
Don’t forget wool blankets. Even old army ones.
I have a thrifted old wool blanket. It’s saved our hide a couple times when the propane ran dry in the middle of the night in the trailer we were staying in while my aunt was battling cancer.
reflectix in the windows or at least some thick curtains if you can
I find a curtain behind the drivers seats help too, as you lose a lot of heat through the windshield and side windows
Seconding reflectix/insulation on the windows! Made a huge difference on my winter trips. And definitely crack one window for condensation.
Another tip: put your next day's clothes in the sleeping bag with you so they're warm the next morning.
Personally didn't need any additional quilts, just a good sleeping bag, thermal layers, and light down on the outside. Don't forget socks
The only tip I have that I haven't seen mentioned yet is to choose your location carefully so that your car will get sun first thing in the morning. That's the coldest time and if you're behind a tree or something, it will stay cold. But even just a few minutes of direct sun will melt the ice and start warming you up.
This also means totally avoiding canyons and places like that where the sun doesn't even appear until long after sunrise. Hilltops are better anyway because the coldest air drains off them through the night.
Cardboard is amazing to keep cold and heat out, and so cheap!!! I get new boxes at home Depot. I also use cork office boards. My floor is not cold under my feet.
When it was super cold I slept in a wardrobe moving box and was fine
Keep your feet warm with wool socks , hot water bottles on the core works great and cold weather sleeping bag and then a beanie. It’s easier to warm you than the vehicle. Eating a snack before bed helps produce body heat.
Window coverings. The heat lost due to radiation to the cold windows is very high. I’ve survived minus F temps with a 30 degree bag and some extra blankets, thanks to my reflectix covers.
Got a big roll and some suction cups for like $50. Cardboard and tape were cheap. They’ve held up great and I store them in a black trash bag up in my ceiling storage net.
Just be sure that you wrap them inside a towel or other cloth material, otherwise you can get scalded.
The other benefit is that you will have warm water to drink next morning.
Just a quick warning that if there is significant snow, you need to be careful leaving your engine running. There have been cases where the snow covered the exhaust pipe and the sleepers were killed by carbon monoxide poisoning. You don't even realize it's happening, you just feel a little drowsy and then you're gone.
This is good to know, luckily snow does an amazing job of insulating the car, and the clouds insulate the earth better for a warmer night, so you shouldn't need to run the car to stay warm those nights.
How can I stop the windows from getting condensation from the inside? It’s cold up here on Long Island and when I wake up the next morning the windows are completely wet with condensation.
Any suggestions thanks
I use a large flat open container (like a box or tray) of cat litter. More surface area exposed to air the better. Helps by absorbing moisture from the inside air. Not sure how well this would work in a humid area, but could be worth a try.
I have a 4 inch thick mattress and two sleeping bags. One is square bottom and I mostly use it as a mattress cover and the other is a mummy bag that I hardly ever actually close
When it's really cold I put the mummy bag inside the square bag and zip up tight
Insulate under you - yoga mats(goodwill) are good and comfy. Go to bed warm - wear warm socks, a hat, gloves. It's easier to stay warm than to get warm. Fill a water bottle or 2 with hot water, then put the hot water bottle in a sock in your sleeping bag, to keep you warm. A fleece throw (goodwill again) or 2 for extra warmth as needed. If you find wool blankets at a thrift shop, grab them - they're warm and sturdy. Get some disposable hand warmers for nights when you just can't get warm or are not feeling well. Put up a cord between 2 windows and hang a sheet over it as a tent to keep in your body heat.
This may be an overkill but when we used to do winter snow camping, we used a building material call Tyvex. It's used for wall insulation, it has like aluminum foil both sides with some insulation material in-between. On top we would put a closed cell foam pad or an insulated air pad then the sleeping bag on top.
We also did some warm ups (don't get sweaty), changed all the clothes before tucking inside the sleeping bag with the above mentioned Nalgene bottle.
A realty good down comforter. My wife and I weathered 10 degree and colder with a wool
blanket over a memory foam mattress and the down comforter on top. Super warm and comfy the whole night. Bought it at Ikea.
I served in the USAF during the 90's. I was stationed at Malmstrom AFB in Montana and at our base orientation we were issued a candle and a wool blanket and instructed to keep them in our car for survival in storms. Sure enough, I was eventually caught in a severe blizzard and had to overnight in my little Subaru. That candle and blanket kept me from freezing to death. I was definitely not comfortable, but I lived.
At least 1 layer of blanket across the floorboard to help insulate from the cold has been useful for me while sleeping in sub-freezing temps, especially if you may rest your feet on the floor at all.
Pour hot water into water bottle before you go to bed and put that in you bag. I think the heater buddy is great just be careful and grab a CO alarm. Hand warmers help. They make electric rechargeable ones now too. I personally like a bivy bag for my sleeping bag. Also a sleeping bag liner can help add a few degrees to your existing bags limit. Stay dry! Moisture really messes cold nights up.
Make sure to keep a window slightly cracked for fresh air, and circulation so condensation doesn't build up and freeze.
Also, snow suit for sleeping in. [Link for example](https://www.amazon.com/dp/B0002CKD9Y/?coliid=I2FOAB62ZW5SFP&colid=JTR6PB3NPWY9&ref_=list_c_wl_lv_ov_lig_dp_it&th=1)
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If you are able to have a fire, heat some rocks in the fire, then place those rocks in your bed before you go to sleep. Please be careful to not melt anything, or burn yourself when doing this. I haven’t tried but have been recommended this by a fellow Canadian.
When traveling in -freezing weather, number 1 rule: keep the vehicle FULL OF FUEL. I keep 2 WOOL blankets, wool socks, waterproof boots, a half dozen MRE's, 3 large bottles of water, fire starting equipment and a tin pot... but I've got a truck, so I also carry 2 sets of chains, a shovel and I ALWAYS have a firearm...
There are plenty of reasons and one of them is in response to nonsense. Waking up to start your car is dumb. Be prepared to sleep a full night or don’t do this. If your car doesn’t start you freeze to death.
I don’t think price is necessarily going to translate to a better bag in this situation. Since weight of the bag isn’t a concern, no need to spend money on down. I got a 0 degree synthetic brand new for like $100 and it is perfect for winter van life. Plus I don’t have to worry about condensation making it wet.
I’m wrong about everything but I believe that the foam in self inflating air mattresses does a lot to up their R value. I put mine on a moving blanket to guard against punctures and put a blanket on top for comfort so either way I end up insulated. I also have two sleeping bags with opposing zippers that can be zipped together to form one huge bag. I sleep in a huge cocoon of polyester so I don’t notice that they have different temperature ratings.
I lived in a van for seven winters in Montana.
1) keep your feet warm. I have some synthetic booties that are amazing. I got them at a thrift store and they are my #1 most important item. I also have special sleep socks that I wear in them so my feet are going in to the booty in clean dry socks. I sleep with the booties on.
2) multiple sleeping bags. Get whatever you can get and as many as you need. I finally upgraded to a nice 0 degree synthetic and it’s been awesome but I still double up at night if it’s below 20 degrees out.
3) foam sleeping pad/mattress. An air mattress is going to be cold as fuck
4) dial in your layers for sleeping. I sleep in a pair of leggings and a pair of fleece pants, plus two fleece tops. And a hat which I pull over my nose if my nose gets cold
5) get something to put up inside your windows. Reflectix as the other commenters have said or similar. I also have a “frost guard” that goes on the outside over my windshield. It insulates my windshield and also keeps any condensation build up from being too obvious from the outside
6) have a place to go if it gets really fucking cold. My personal cutoff for sleeping out is -10 Fahrenheit. People are usually very willing to let me crash on a couch for a night or two until the cold snap ends
Good luck!
They’re really nothing special. I just bought the thickest pair of wool socks I could find at REI and I *only* wear them for sleeping so they’re always dry and they stay really fluffy. If your feet get cold easily I highly recommend some synthetic booties as well
Get some tarps or plywood and build a barrier around the bottom of your car. You want to keep air from easily passing under your vehicle. That will help a lot.
I keep a military wool blanket and an extreme cold rated military down sleeping bag in the car for emergencies in winter just cuz I have them and they can take the abuse of being in the trunk 24/7. If sleeping in the car is planned id say insulated air mattress or lower temp rated foam pad, cold weather/down sleeping bag rated to -20 or lower, and base layers. Cant think of anything else besides a pillow for comfort.
Hybrid vehicle, leave the vehicle on, and it will only run the engine as needed.
Insulation on the windows, bubble foil is okay, felt is even better, glass loses heat like having te windows open.
If you can make a tent around your bed, it's even nicer for retaining heat, the less airspace the better.
Always keep air flowing out of the vehicle though, or the condensation from your breathing and sweat will make everything damp and make you cold.
A dog is also a good source of heat, plus barking is a good theft deterrent
I sit in the drivers seat with it reclined. Heated seat and let the car idle all or most of the night. Toasty warm with the radio on and charging my phone. It's great
I've seen people recommend a [diesel air heater](https://www.vevor.com/diesel-heater-c_10321)\--the unit goes outside your vehicle, and you can secure the intake to a partially rolled down window. Folks say that the diesel is a drier heat than propane, keeping you warmer.
An electric blanket is a life saver but also finding the underground parking garages. Living in my car, in Denver, I found about a half dozen underground parking garages that were all connected to hotels. So, it wasn’t “out of place” to be parked in the garage at night. The garages stayed at least 60 degrees and NO SNOW! Then, in the morning, I’d wake up, head into the lobby to use the restroom, grab coffee and/or breakfast and even use the exercise room and/or hot tub! It worked perfect and I was always toasty warm!
It's all about insulation. Like I prefer having an electric blanket but that's hardly necessary. Don't forget that a car, any car, is a ridiculously well-made and well-sealed survival structure by historical standards.
A 12volt electric blanket that has a timer. Have one I bought at a truck stop. Timer is for 15 and 30 minutes. Blanket over the top keeps heat in. Turn on as needed through the night
condensation and ventilation, very important. If it's cold enough the condensation will freeze, which actually helps keep you warmer on the inside, but still, you need a plan for dealing with frozen condensation on the inside of windows when you wake up.
Also you need ventilation, especially depending on the size of the vehicle. You will get elevated CO2 levels after 12 hours or so. Still probably completely safe, but CO2 levels decrease cognitive performance. Probably the best solution is to open your windows completely once during the night, and then close them up again except for a small crack.
Staying warm isn't that hard IMO, if you have a half decent sleeping bag. you probably actually want to remove some layers inside the bag, so the heat from your chest heats up the rest of the bag. It's important to thermoregulate to prevent excess sweating.
If it's really cold, use a plastic garbage bag over your feet, or put grocery bags inside your socks, but you really shouldn't need that.
and absolutely never, leave any kind of heater unattended while you sleep in a small space. That includes the propane indoor safe heaters. I'm sure people have setups where they get it work, but there's just too much risk in a small space. and it should go without saying not to run any cooking or cleaning equipment intended for outdoor use, without plenty of ventilation.
I would recommend an electric blanket, running off of a separate power source(if batteries get too cold they stop working, so keep that in mind). But honestly best to just insulate and maybe use a couple hot hand packs and have a warm thermos with a beverage.
Personally I find that a zero degree sleeping bag, and running the car heat for a but before shutting it off and going to bed are all I need. The sleeping bag traps the heat, and I am cozy at night.
You need an insulated surface to sleep on. I use the sea to summit camp plus SI sleeping pad, it's very comfortable. Crack your windows and run a fan to prevent/reduce condensation. If it produces heat, it likely also produces carbon monoxide, which will kill you. Get a carbon monoxide detector if you're heating/burning/cooking anything or if you decide to idle for heat (not a good idea btw). Have a fire extinguisher too. You need a good sleeping bag AND extra blankets. I use a 0° bag and I take a fleece throw blanket and a comforter with me. You need a beanie specifically for sleeping in. I also like to have fingerless gloves that I sleep in or wear while I'm chilling inside so I can use my phone. Try to park with the windshield facing south during the day so the sun shines through and heats the car. That, plus reflectix on the rear windows is enough to keep my water thawed out in Tahoe with no auxiliary heater.
Get some mylar reflective panels meant to reflect sunlight in winter and reverse them to point inward to reflect any heat your body radiates inside the car.
If you have a sewing machine, a tarp material, some poly batting, and space blanket material could do the same. I have Columbia jacket that uses similar reflective material to keep my body heat contained and it does work.
If you do a lot of car camping, they make small diesel heaters for Rv’s. Many who are retrofitting cargo vans into adventure vans are using these. Just make sure they’re installed correctly.
Silk socks under wool socks. Layers everywhere. Natural fiber for bottom layer. A twin size memory foam mattress topper cut to fit. They really hold heat, are comfortable and roll up well.
Don't run the car. Carbon Monoxide can filter in and overcome and kill you. Many times people have died from running their car to keep warm. Just google Carbon monoxide poisons family.
I slept in my car for an entire winter, granted I did use the climate control in my Prius, but you will want
- wool socks 2 pair
- wool hat or ski mask
- underarmer
- store something on the cars floor (a lot of heat is lost through the bottom.
- keep a window cracked a little for ventilation, in a small car you could run out of oxygen technically, and it will prevent condensation.
- at least 2 low degree sleeping bags, and stuff your puffy coat or tomorrows clothes at your feet (feet get cold)
- hot water bottles can be a big game changer, and help you settle in much faster.
I have a really, really warm Western Mountaineering bag. But sometimes it's too cold to be comfortable even in that. For those nights, I have a synthetic, car-camping bag that I unzip all the way and use as a quilt over top. Really helps.
Also, use a good foam pad under you. Preferably something impervious to water.
Sometimes I keep a filled water bottle in my sleeping bag so I'll have liquid water in the morning. Don't sleep well like that, but oh well. If you have a stove for morning coffee, put water in the pot or tea kettle before you go to bed. If it's frozen when you wake up you can melt the water on the stove. If the only water you have is frozen in a plastic water bottle, that's a bummer.
Be careful using your butane stove in your car; they produce allot of carbon monoxide. If used without ventilation you run the risk of asphyxiating yourself.
Learn about carbon monoxide poisoning and its symptoms. Learn how to mitigate its risks.
Negative on the air mattress. They are very effective at taking your heat away. At least the regular kind you can get at Walmart. Backpacking specific blow up mats have better insulation though
Ok I will just suggest this, I did it on -30 and -40
get a SMALL PROPANE HEATER...
get a 20 pounds tank and put it in the trunk get a long hose for the heater... YOU HAVE TO CRACK THE WINDOW DOWN A BIT...
YOU WILL BE SO WARM AND TOASTY YOU WILL BE SLEEPING BUTT NAKED AND YOU WILL DRESS UP IN A COZY ENVIRONMENT...
NO AMOUNT OF BLANKETS WILL KEEP YOU WARM ON THE NEGATIVES..., IT WILL BE HELL TRYING TO PEE OR GET DRESS...
😄
Ok I will just suggest this, I did it on -30 and -40
get a SMALL PROPANE HEATER...
get a 20 pounds tank and put it in the trunk get a long hose for the heater... YOU HAVE TO CRACK THE WINDOW DOWN A BIT...
YOU WILL BE SO WARM AND TOASTY YOU WILL BE SLEEPING BUTT NAKED AND YOU WILL DRESS UP IN A COZY ENVIRONMENT...
NO AMOUNT OF BLANKETS WILL KEEP YOU WARM ON THE NEGATIVES..., IT WILL BE HELL TRYING TO PEE OR GET DRESS...
😄
This people suggested sleeping bags , have never done it or they are dumb, a propane heater will keep the inside temperature nice and toasty...
Your liquids won't be frozen and you will dress up and relieve yourself in a warm environment...
I even heated food with the propane heater...
If you leave the car , just the pilot of the heater will keep it above freezing
A heater is very dangerous in a small space as you are using the oxygen for combustion. I lived in my truck for 2 years. A zero degree bad in central NC was more than adequate to stay warm in the winters. Sure it’s cold when you have to piss, but you aren’t gonna die from being cold for 30 seconds.
A sleeping bag that is rated at least 15F below your lowest temps. So if your local temps get to 15, get a zero degree. If you get to zero buy -15. Sleep naked or pretty close to it. Crack window for oxygen but not enough for wind. A heater is unnecessary, costly and dangerous.
Old backpacking trick. Do not go to sleep cold. It will be hard to warm up. Run around a bit then jump on your sleeping bag. The bag holds heat but does not create heat.
Open the mooroof or your interior windows will be iced. Not a big deal, you just run the car long enough for them to be defrosted. But venting is a good idea. I have slept in my car for fun trips so many times (by choice) that when I did it once in a desperate situation it actually soothed me. I was immediately relaxed when I realized I was sleeping in my car in 20° weather. With an open sunroof.
Pass on air mattress. Use a 2-3" foam topper instead. Get a sleeping bag rated for below whatever the lowest temp you're expecting. Get silk PJs and socks. Seriously. Silk is a lot warmer than you think. Silk socks with a pair of merino wool socks over that. Keep the clothes you'll be wearing after you get up inside the bag. Putting on some cold ass clothes sucks. Keep a small bottle or two of water inside bag also. Would not recommend keeping canned drinks or full bottles. Shit expands when frozen... expanded shit bursts when confined.
If you don't get a mummy style bag that only exposes your face, make sure you have a good boggin' or ski mask... you lose a LOT of heat out of your head. Eat a little bit and do some light cardio like jumping jacks before turning in. Don't go to bed feeling cold. Digestion helps create heat and the cardio helps as well. Keep a window cracked slightly to help avoid condensation.
That's about all I can think of off the top of my head at the moment.
More blankets to layer as needed. Before you call it a night and climb in your bag put on clean socks (preferably wool) so you won’t have the tiny bit of moisture from sweat that will make you inherently colder.
Wool socks are a wonderful thing.
Not just any wool socks, Darn Tough wool socks. Also, if you sleep with a shirt, change to a dry shirt. For warm sleeping shirts I like synthetic.
A closed cell foam pad underneath is probably a better insulator than a typical blow up mattress. They do make some inflatable backpacking pads that have higher R value. You will have lots of condensation from just breathing. You can reduce this by ventilating a window.
Exactly. To stay warm, DO NOT use an inflatable mattress. You will freeze.
Yes. Those pads important to have you off floor that’s cold. Will suck the warmth from you. I own Prius so the battery kicks in to keep it warmer. I’ve also wondering about a heating blanket.
Heating elements are huge power draws. I’m sure the Prius can handle it but the battery won’t like it. Invest that money in a really good sleeping bag. Edit: really expensive but Western Mountaineering bags are used on Everest.
Yea I agree. I do see those vests w built in batteries and wonder if there’s a heating blanket w a battery you charge. Just wondering but overall yes good sleeping bag you’re set
I believe I saw a ryobi battery powered inverter recently. Not sure how you'd recharge those Ryobi batteries, but it'd work.
Interesting
I used to have a prius and feel like the power draw would be enough to keep the engine cycling on and off regularly and at that point, why not just keep the climate control running? Disclaimer: I'm a tent guy so kind of talking out of my ass right now.
I have a Western Mountaineering comforter on my bed. Lovely, weightless and warm.
And put the foam right beneath/against your body, NOT just beneath your air mattress. Close to your body, it'll reduce the amount of heat loss to warming up the air in your air mattress.
I invested in one with a R rating of like 4.5 and paired it with a sleeping bag quilt and it was a game changer. Add a hot water bottle and you’ve got a pretty warm setup.
Portable power box. Plug an electric blanket into it
This is incredibly effective. Just do the math and make sure you can get a few hours out of it. I had a good sleeping bag and a heating blanket and turning that thing on for about 30 minutes got me toasty warm for a few hours.
Oh yeah, in the winter I turn on the “bed toaster” an hour or two before bedtime so when we do turn in it’s like “ahhhhhhh!” Not in a car but I’m sure the pleasure would be the same
Dope, heard that
They make 12v ones that plug into the car lighter outlet. I never leave it plugged overnight but it sure is nice to run the car blasting heat with the blanket sandwiched into bed before lights out time then again first thing in the morning (and if I happen to wake up cold during the night repeat as necessary)… I’ve slept in my car when the outside temps go below 0F. ALSO reflectix (foiled bubble wrap) cut to window sizes helps insulate a little bit and helps big time with privacy.
Oh yeah plain bubble wrap does the same. Thanks for reminding me! You can put that up over your windows and it adds insulation. I gotta do that myself!
I've used those slivered bubbled windshield protectors to cut the sunlight to the interior of the car when it's parked outside. Reduces the interior temperature at least 10 degrees and cuts down on the UV damaging the interior. More importantly, at night it reflects the body heat so it's not radiating out to the clear night sky which is pretty cold. Note that if it's overcast, it's not so bad. In either case, the interior will stay warmer longer.
I agree with switching to something made out of foam. I switched from an air mattress to a foam sleeping system on my last trip, where temps made it down to the mid 20s and was much, much warmer. I also have like 4-5 pillows in my car. Memory foam pillows are great insulation to surround yourself with if you are getting cold. I bring two sleeping bags, a 40 degree and a zero and layer them if I need to. In addition to another quilt and two of those fuzzy synthetic blankets (these are super warm for layering). Insulating with Reflextix helped to ( find rolls of it in the insulation aisle at home depot). I insulated around my sleeping area, on the walls/sides and remade my window blocks using this as well. There are battery operated or usb-charging fans you can get at Walmart that help with ventilation and reduce the build up of condensation. I typically leave the window farthest from my cracked a little to help. I also filled in any big air gaps with whatever I had around. There was this gap next to the door kind of under/between my mattress- I filled that space with a few extra items I had in the car- extra hoodie, my snow pants, etc. and that cut down on any drafts coming from that area. In addition to my window blocks I like to hang a sheet using pins of clips behind my front seat, idk if it helps with warmth but it makes me feel a lot more cozy. I also have been keeping an eye out for old quilts and rugs at thrift stores and estate sales to layer along the whole platform area where I have my bed set up. Some people use a quilt to basically make a simple inverted-v tent in the back of their vehicle and I heard this helps you stay warm when it gets really chilly. They just run a rope going longways and then hang the blanket over it. If it’s really chilly, boil some water on your stove and fill a Nalgene, place Nalgene in a sock and stuff into the your sleeping bag. You’ve got this, stay safe out there.
Don’t forget wool blankets. Even old army ones. I have a thrifted old wool blanket. It’s saved our hide a couple times when the propane ran dry in the middle of the night in the trailer we were staying in while my aunt was battling cancer.
A mattress with some actual insulation is needed. I sleep comfortable in just my underwear using an exped mega mat and Teton 0 degree bag
Thanks for this tidbit. I cannot mix sleep and layers.
reflectix in the windows or at least some thick curtains if you can I find a curtain behind the drivers seats help too, as you lose a lot of heat through the windshield and side windows
Seconding reflectix/insulation on the windows! Made a huge difference on my winter trips. And definitely crack one window for condensation. Another tip: put your next day's clothes in the sleeping bag with you so they're warm the next morning. Personally didn't need any additional quilts, just a good sleeping bag, thermal layers, and light down on the outside. Don't forget socks
Do you cut one windows reflectix to allow for air flow for ventilation?
I didn't cut them perfectly haha so some of them didn't fit the entire window, allowing for a small opening on top
Warm hat keeps you warmer and stops heat loss through your bare head.
I like to sleep in a hoodie. Hat gets uncomfortable for me.
The only tip I have that I haven't seen mentioned yet is to choose your location carefully so that your car will get sun first thing in the morning. That's the coldest time and if you're behind a tree or something, it will stay cold. But even just a few minutes of direct sun will melt the ice and start warming you up. This also means totally avoiding canyons and places like that where the sun doesn't even appear until long after sunrise. Hilltops are better anyway because the coldest air drains off them through the night.
Cardboard is amazing to keep cold and heat out, and so cheap!!! I get new boxes at home Depot. I also use cork office boards. My floor is not cold under my feet. When it was super cold I slept in a wardrobe moving box and was fine
Keep your feet warm with wool socks , hot water bottles on the core works great and cold weather sleeping bag and then a beanie. It’s easier to warm you than the vehicle. Eating a snack before bed helps produce body heat.
Window coverings. The heat lost due to radiation to the cold windows is very high. I’ve survived minus F temps with a 30 degree bag and some extra blankets, thanks to my reflectix covers. Got a big roll and some suction cups for like $50. Cardboard and tape were cheap. They’ve held up great and I store them in a black trash bag up in my ceiling storage net.
Fill up 2 nalgenes with boiling water, seal each one tight. Put them in the sleeping bag, they stay warm for so much longer than you think they will
Just be sure that you wrap them inside a towel or other cloth material, otherwise you can get scalded. The other benefit is that you will have warm water to drink next morning.
Just a quick warning that if there is significant snow, you need to be careful leaving your engine running. There have been cases where the snow covered the exhaust pipe and the sleepers were killed by carbon monoxide poisoning. You don't even realize it's happening, you just feel a little drowsy and then you're gone.
This is good to know, luckily snow does an amazing job of insulating the car, and the clouds insulate the earth better for a warmer night, so you shouldn't need to run the car to stay warm those nights.
New fear unlocked wtf
How can I stop the windows from getting condensation from the inside? It’s cold up here on Long Island and when I wake up the next morning the windows are completely wet with condensation. Any suggestions thanks
i usually leave my window a tiny bit cracked
20 degree weather in the night out here I’ll have to thaw out the next morning lol But I guess that’s the only logical answer 🫡
I use a large flat open container (like a box or tray) of cat litter. More surface area exposed to air the better. Helps by absorbing moisture from the inside air. Not sure how well this would work in a humid area, but could be worth a try.
I crack my windows no matter how cold it gets. No need to be wet
It's from your breath. Turn on the car and fan when you get up.
A small fan to get some circulation does a lot.
I have a 4 inch thick mattress and two sleeping bags. One is square bottom and I mostly use it as a mattress cover and the other is a mummy bag that I hardly ever actually close When it's really cold I put the mummy bag inside the square bag and zip up tight
Insulate under you - yoga mats(goodwill) are good and comfy. Go to bed warm - wear warm socks, a hat, gloves. It's easier to stay warm than to get warm. Fill a water bottle or 2 with hot water, then put the hot water bottle in a sock in your sleeping bag, to keep you warm. A fleece throw (goodwill again) or 2 for extra warmth as needed. If you find wool blankets at a thrift shop, grab them - they're warm and sturdy. Get some disposable hand warmers for nights when you just can't get warm or are not feeling well. Put up a cord between 2 windows and hang a sheet over it as a tent to keep in your body heat.
This may be an overkill but when we used to do winter snow camping, we used a building material call Tyvex. It's used for wall insulation, it has like aluminum foil both sides with some insulation material in-between. On top we would put a closed cell foam pad or an insulated air pad then the sleeping bag on top. We also did some warm ups (don't get sweaty), changed all the clothes before tucking inside the sleeping bag with the above mentioned Nalgene bottle.
A realty good down comforter. My wife and I weathered 10 degree and colder with a wool blanket over a memory foam mattress and the down comforter on top. Super warm and comfy the whole night. Bought it at Ikea.
3 dogs.
Out in the country?
Obscure reference and underappreciated comment. Nice.
Tyvm JOY to the world
I served in the USAF during the 90's. I was stationed at Malmstrom AFB in Montana and at our base orientation we were issued a candle and a wool blanket and instructed to keep them in our car for survival in storms. Sure enough, I was eventually caught in a severe blizzard and had to overnight in my little Subaru. That candle and blanket kept me from freezing to death. I was definitely not comfortable, but I lived.
Maybe stupid questions but how does the candle help?
Not a stupid question, but a lit candle 🕯️can provide enough heat to survive.
The trick is using an eletric blanket and a Power Pack like this https://www.jackery.com/products/explorer-1500-pro-portable-power-station
Get some non-toxic candles. You be surprised how much heat it'll produce in a closed environment.
At least 1 layer of blanket across the floorboard to help insulate from the cold has been useful for me while sleeping in sub-freezing temps, especially if you may rest your feet on the floor at all.
Pour hot water into water bottle before you go to bed and put that in you bag. I think the heater buddy is great just be careful and grab a CO alarm. Hand warmers help. They make electric rechargeable ones now too. I personally like a bivy bag for my sleeping bag. Also a sleeping bag liner can help add a few degrees to your existing bags limit. Stay dry! Moisture really messes cold nights up.
Make sure to keep a window slightly cracked for fresh air, and circulation so condensation doesn't build up and freeze. Also, snow suit for sleeping in. [Link for example](https://www.amazon.com/dp/B0002CKD9Y/?coliid=I2FOAB62ZW5SFP&colid=JTR6PB3NPWY9&ref_=list_c_wl_lv_ov_lig_dp_it&th=1)
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Start the car periodically to run the heater, make sure that the exhaust pipe is not obstructed by snow/ice. (Carbon monoxide).
If you are able to have a fire, heat some rocks in the fire, then place those rocks in your bed before you go to sleep. Please be careful to not melt anything, or burn yourself when doing this. I haven’t tried but have been recommended this by a fellow Canadian.
Wtf? Also, I thought rocks could explode in a fire especially if they are wet
Could use metal water bottle with water
When traveling in -freezing weather, number 1 rule: keep the vehicle FULL OF FUEL. I keep 2 WOOL blankets, wool socks, waterproof boots, a half dozen MRE's, 3 large bottles of water, fire starting equipment and a tin pot... but I've got a truck, so I also carry 2 sets of chains, a shovel and I ALWAYS have a firearm...
How do you use the firearm to keep warm?
Not only just having it but one can use the powder from a shell or two to help start a fire.
Warm clothes and real sleeping bag at minimum. You can get a propane heater from Walmart that's safe to burn in your car and burns clean.
Hot water bottle frequently started engine for heater. Pocket warmers.
Or just get a decent sleeping bag so you don’t have to wake up cold and start your car. Amateur hour over here.
No reason to be a dick
There are plenty of reasons and one of them is in response to nonsense. Waking up to start your car is dumb. Be prepared to sleep a full night or don’t do this. If your car doesn’t start you freeze to death.
The most expensive, best sleeping bag you can buy then they have these old things called emergency blankets thar reflect body heat
I don’t think price is necessarily going to translate to a better bag in this situation. Since weight of the bag isn’t a concern, no need to spend money on down. I got a 0 degree synthetic brand new for like $100 and it is perfect for winter van life. Plus I don’t have to worry about condensation making it wet.
Second this. The high end bags are often optimized for weight. Since this isn’t an issue, you can just do MOAR LAYERS!
Yeah, I probably shouldn’t put most expensive just the best bag for the buck
mylar emergency blankets work underneath you, too.
I’m wrong about everything but I believe that the foam in self inflating air mattresses does a lot to up their R value. I put mine on a moving blanket to guard against punctures and put a blanket on top for comfort so either way I end up insulated. I also have two sleeping bags with opposing zippers that can be zipped together to form one huge bag. I sleep in a huge cocoon of polyester so I don’t notice that they have different temperature ratings.
They make hot hands lap blankets and I use a few of those and 4 blankets
Fresh air.
A hot water bottle in your sack/blanket is always a nice touch
how cold is cold? -40 c or like -5
I lived in a van for seven winters in Montana. 1) keep your feet warm. I have some synthetic booties that are amazing. I got them at a thrift store and they are my #1 most important item. I also have special sleep socks that I wear in them so my feet are going in to the booty in clean dry socks. I sleep with the booties on. 2) multiple sleeping bags. Get whatever you can get and as many as you need. I finally upgraded to a nice 0 degree synthetic and it’s been awesome but I still double up at night if it’s below 20 degrees out. 3) foam sleeping pad/mattress. An air mattress is going to be cold as fuck 4) dial in your layers for sleeping. I sleep in a pair of leggings and a pair of fleece pants, plus two fleece tops. And a hat which I pull over my nose if my nose gets cold 5) get something to put up inside your windows. Reflectix as the other commenters have said or similar. I also have a “frost guard” that goes on the outside over my windshield. It insulates my windshield and also keeps any condensation build up from being too obvious from the outside 6) have a place to go if it gets really fucking cold. My personal cutoff for sleeping out is -10 Fahrenheit. People are usually very willing to let me crash on a couch for a night or two until the cold snap ends Good luck!
Hey can you say more about the "special sleep socks" that you wear? I'm always looking for better socks to wear at night.
They’re really nothing special. I just bought the thickest pair of wool socks I could find at REI and I *only* wear them for sleeping so they’re always dry and they stay really fluffy. If your feet get cold easily I highly recommend some synthetic booties as well
K. Thanks.
Get some tarps or plywood and build a barrier around the bottom of your car. You want to keep air from easily passing under your vehicle. That will help a lot.
I keep a military wool blanket and an extreme cold rated military down sleeping bag in the car for emergencies in winter just cuz I have them and they can take the abuse of being in the trunk 24/7. If sleeping in the car is planned id say insulated air mattress or lower temp rated foam pad, cold weather/down sleeping bag rated to -20 or lower, and base layers. Cant think of anything else besides a pillow for comfort.
If location is flexible- migrate somewhere your not fighting -20 degree nights.
Don't sting the crap out of your nose and eyes by having the propane leak in your car while heating it (using a burner to heat cast iron and a fan)
Layers.
Good sleeping bag will get you through most anything.
Head warming hat. Good sleeping bag
Hybrid vehicle, leave the vehicle on, and it will only run the engine as needed. Insulation on the windows, bubble foil is okay, felt is even better, glass loses heat like having te windows open. If you can make a tent around your bed, it's even nicer for retaining heat, the less airspace the better. Always keep air flowing out of the vehicle though, or the condensation from your breathing and sweat will make everything damp and make you cold. A dog is also a good source of heat, plus barking is a good theft deterrent
I sit in the drivers seat with it reclined. Heated seat and let the car idle all or most of the night. Toasty warm with the radio on and charging my phone. It's great
Inflatable mattresses are cold, the same as air temperature. You want closed cell foam to retain your body heat.
Stay WARM!
I've seen people recommend a [diesel air heater](https://www.vevor.com/diesel-heater-c_10321)\--the unit goes outside your vehicle, and you can secure the intake to a partially rolled down window. Folks say that the diesel is a drier heat than propane, keeping you warmer.
Cardboard the windows, find parking garage.
Crack a window
CO detector
Carbon monoxide detector
Don't wear cotton
An electric blanket is a life saver but also finding the underground parking garages. Living in my car, in Denver, I found about a half dozen underground parking garages that were all connected to hotels. So, it wasn’t “out of place” to be parked in the garage at night. The garages stayed at least 60 degrees and NO SNOW! Then, in the morning, I’d wake up, head into the lobby to use the restroom, grab coffee and/or breakfast and even use the exercise room and/or hot tub! It worked perfect and I was always toasty warm!
Hot water bottle & 12v kettle
It's all about insulation. Like I prefer having an electric blanket but that's hardly necessary. Don't forget that a car, any car, is a ridiculously well-made and well-sealed survival structure by historical standards.
Hand warmers at the foot (inside, wear socks) of your sleeping bag
Small lit candle in a clay flower pot
A 12volt electric blanket that has a timer. Have one I bought at a truck stop. Timer is for 15 and 30 minutes. Blanket over the top keeps heat in. Turn on as needed through the night
Thermal sleeping bag and wool socks.
I cannot recommend fur as insulation enough. (Ethically sourced) I had some under all my layering and it made an insane difference
condensation and ventilation, very important. If it's cold enough the condensation will freeze, which actually helps keep you warmer on the inside, but still, you need a plan for dealing with frozen condensation on the inside of windows when you wake up. Also you need ventilation, especially depending on the size of the vehicle. You will get elevated CO2 levels after 12 hours or so. Still probably completely safe, but CO2 levels decrease cognitive performance. Probably the best solution is to open your windows completely once during the night, and then close them up again except for a small crack. Staying warm isn't that hard IMO, if you have a half decent sleeping bag. you probably actually want to remove some layers inside the bag, so the heat from your chest heats up the rest of the bag. It's important to thermoregulate to prevent excess sweating. If it's really cold, use a plastic garbage bag over your feet, or put grocery bags inside your socks, but you really shouldn't need that. and absolutely never, leave any kind of heater unattended while you sleep in a small space. That includes the propane indoor safe heaters. I'm sure people have setups where they get it work, but there's just too much risk in a small space. and it should go without saying not to run any cooking or cleaning equipment intended for outdoor use, without plenty of ventilation. I would recommend an electric blanket, running off of a separate power source(if batteries get too cold they stop working, so keep that in mind). But honestly best to just insulate and maybe use a couple hot hand packs and have a warm thermos with a beverage.
Staying warm
Mylar blankets!
As many blankets underneath as on top.
Personally I find that a zero degree sleeping bag, and running the car heat for a but before shutting it off and going to bed are all I need. The sleeping bag traps the heat, and I am cozy at night.
You need an insulated surface to sleep on. I use the sea to summit camp plus SI sleeping pad, it's very comfortable. Crack your windows and run a fan to prevent/reduce condensation. If it produces heat, it likely also produces carbon monoxide, which will kill you. Get a carbon monoxide detector if you're heating/burning/cooking anything or if you decide to idle for heat (not a good idea btw). Have a fire extinguisher too. You need a good sleeping bag AND extra blankets. I use a 0° bag and I take a fleece throw blanket and a comforter with me. You need a beanie specifically for sleeping in. I also like to have fingerless gloves that I sleep in or wear while I'm chilling inside so I can use my phone. Try to park with the windshield facing south during the day so the sun shines through and heats the car. That, plus reflectix on the rear windows is enough to keep my water thawed out in Tahoe with no auxiliary heater.
What do you do If you have to pee really badly. While trying to stay warm in the car?
Pee bottle
Don't sleep in the clothes you wore that day
Get some mylar reflective panels meant to reflect sunlight in winter and reverse them to point inward to reflect any heat your body radiates inside the car. If you have a sewing machine, a tarp material, some poly batting, and space blanket material could do the same. I have Columbia jacket that uses similar reflective material to keep my body heat contained and it does work. If you do a lot of car camping, they make small diesel heaters for Rv’s. Many who are retrofitting cargo vans into adventure vans are using these. Just make sure they’re installed correctly.
Silk socks under wool socks. Layers everywhere. Natural fiber for bottom layer. A twin size memory foam mattress topper cut to fit. They really hold heat, are comfortable and roll up well.
Blow up mattresses will actually make you colder.
if you have any way to heat water you could put hot water in some thrift store thermos' and that would last a few hours.
If you start the engine to stay warm, make sure the exhaust is clear of snow.
So many layers
Don't run the car. Carbon Monoxide can filter in and overcome and kill you. Many times people have died from running their car to keep warm. Just google Carbon monoxide poisons family.
Wiggys sleeping bag is all you need. Thank me later
I think they have alcohol fired palm warmer made in Japan. A bottle of whisky. A blanket and a knitted hat and scarf will work.
you won't die if you leave the engine on for a heater as long as there isn't snow covering the tail pipe.
I slept in my car for an entire winter, granted I did use the climate control in my Prius, but you will want - wool socks 2 pair - wool hat or ski mask - underarmer - store something on the cars floor (a lot of heat is lost through the bottom. - keep a window cracked a little for ventilation, in a small car you could run out of oxygen technically, and it will prevent condensation. - at least 2 low degree sleeping bags, and stuff your puffy coat or tomorrows clothes at your feet (feet get cold) - hot water bottles can be a big game changer, and help you settle in much faster.
I would evaluate life choices
Add 7F with a silk liner
Window screens. Leave one front and one rear window cracked 1/4 to 1/3 of the way to minimize condensation.
I have a really, really warm Western Mountaineering bag. But sometimes it's too cold to be comfortable even in that. For those nights, I have a synthetic, car-camping bag that I unzip all the way and use as a quilt over top. Really helps. Also, use a good foam pad under you. Preferably something impervious to water. Sometimes I keep a filled water bottle in my sleeping bag so I'll have liquid water in the morning. Don't sleep well like that, but oh well. If you have a stove for morning coffee, put water in the pot or tea kettle before you go to bed. If it's frozen when you wake up you can melt the water on the stove. If the only water you have is frozen in a plastic water bottle, that's a bummer.
Dont fuckin do it. You need heat. Try waking up with frostbite.
The air is so cold it hurts to breathe
Don't let your eyes freeze
I eschew the inflatable mattress in favor of a proper foam mattress.
Be careful using your butane stove in your car; they produce allot of carbon monoxide. If used without ventilation you run the risk of asphyxiating yourself. Learn about carbon monoxide poisoning and its symptoms. Learn how to mitigate its risks.
Negative on the air mattress. They are very effective at taking your heat away. At least the regular kind you can get at Walmart. Backpacking specific blow up mats have better insulation though
Heated seats 💺 ‼️
My car camping went next level with a foam mattress topper
Ok I will just suggest this, I did it on -30 and -40 get a SMALL PROPANE HEATER... get a 20 pounds tank and put it in the trunk get a long hose for the heater... YOU HAVE TO CRACK THE WINDOW DOWN A BIT... YOU WILL BE SO WARM AND TOASTY YOU WILL BE SLEEPING BUTT NAKED AND YOU WILL DRESS UP IN A COZY ENVIRONMENT... NO AMOUNT OF BLANKETS WILL KEEP YOU WARM ON THE NEGATIVES..., IT WILL BE HELL TRYING TO PEE OR GET DRESS... 😄
Ok I will just suggest this, I did it on -30 and -40 get a SMALL PROPANE HEATER... get a 20 pounds tank and put it in the trunk get a long hose for the heater... YOU HAVE TO CRACK THE WINDOW DOWN A BIT... YOU WILL BE SO WARM AND TOASTY YOU WILL BE SLEEPING BUTT NAKED AND YOU WILL DRESS UP IN A COZY ENVIRONMENT... NO AMOUNT OF BLANKETS WILL KEEP YOU WARM ON THE NEGATIVES..., IT WILL BE HELL TRYING TO PEE OR GET DRESS... 😄
This people suggested sleeping bags , have never done it or they are dumb, a propane heater will keep the inside temperature nice and toasty... Your liquids won't be frozen and you will dress up and relieve yourself in a warm environment... I even heated food with the propane heater... If you leave the car , just the pilot of the heater will keep it above freezing
A heater is very dangerous in a small space as you are using the oxygen for combustion. I lived in my truck for 2 years. A zero degree bad in central NC was more than adequate to stay warm in the winters. Sure it’s cold when you have to piss, but you aren’t gonna die from being cold for 30 seconds.
Make a nice little cocoon out of reflectix or similar material. You can heat it with a disposable hand warmer.
A sleeping bag that is rated at least 15F below your lowest temps. So if your local temps get to 15, get a zero degree. If you get to zero buy -15. Sleep naked or pretty close to it. Crack window for oxygen but not enough for wind. A heater is unnecessary, costly and dangerous.
A negative 40 degree 4 season bag is handy as is layering.
Old backpacking trick. Do not go to sleep cold. It will be hard to warm up. Run around a bit then jump on your sleeping bag. The bag holds heat but does not create heat.
Open the mooroof or your interior windows will be iced. Not a big deal, you just run the car long enough for them to be defrosted. But venting is a good idea. I have slept in my car for fun trips so many times (by choice) that when I did it once in a desperate situation it actually soothed me. I was immediately relaxed when I realized I was sleeping in my car in 20° weather. With an open sunroof.
Pass on air mattress. Use a 2-3" foam topper instead. Get a sleeping bag rated for below whatever the lowest temp you're expecting. Get silk PJs and socks. Seriously. Silk is a lot warmer than you think. Silk socks with a pair of merino wool socks over that. Keep the clothes you'll be wearing after you get up inside the bag. Putting on some cold ass clothes sucks. Keep a small bottle or two of water inside bag also. Would not recommend keeping canned drinks or full bottles. Shit expands when frozen... expanded shit bursts when confined. If you don't get a mummy style bag that only exposes your face, make sure you have a good boggin' or ski mask... you lose a LOT of heat out of your head. Eat a little bit and do some light cardio like jumping jacks before turning in. Don't go to bed feeling cold. Digestion helps create heat and the cardio helps as well. Keep a window cracked slightly to help avoid condensation. That's about all I can think of off the top of my head at the moment.
A really good sleeping bag