Winter happens. Some places are milder than others, but even in southern Arizona, you can get the occasional cold shot. With climate change turning the weather so wacky these days, a sudden chill can happen practically anytime, anywhere. How do you deal with that when you’re living in a van? There are many ways.
Drive Someplace Warm

The most basic way to not be cold is to simply drive somewhere that isn’t. After our mad dash van build and tying up loose ends in New Hampshire, we were still miserably cold despite it being late April. So we cannonballed to Virginia Beach and spent a week enjoying the warmth. Similarly, I’m spending the winter in Quartzsite, Arizona because I don’t want to deal with anything resembling a real winter. The beauty of this life is that if you don’t like where you are, your house has wheels, so you can move it someplace else.
This is particularly true if you’re up at altitude, like Flagstaff, Arizona. The temperature drops 3º for every 1,000 feet of elevation. Flagstaff sits at nearly 7,000 feet above sea level, which makes it about 21º colder. That’s great for staying cool in the summer, but not so good during winter. The lower you are, the warmer you’ll be.
That said, you’re not always going to be able to outrun cold temperatures. If it was that easy, I wouldn’t be writing about it. That’s where the rest of these tips come in.
Insulation

The topic of insulation could be a post in itself. There are so many options out there, from standard household insulation to spray foam to wool. Different solutions work best for different needs, so I’m not going to get into specifics here. What I will say is that you should absolutely have some kind of insulation in your van to help keep the heat in — and, during hot weather, keep the heat out.
We ended up using a combination of Reflectix and wool batting from a fabric store since we couldn’t get my preferred option of Havelock Wool in time. It lines the lower walls of the van. The high-top conversion has about an inch of insulation between the fiberglass layers of the roof, which helps. I also have Reflectix in all the windows, painted black on one side for a little bit of stealth (which doesn’t really exist anyway). Depending on which color is facing out, I can either reflect the heat in rather than let it escape through the windows at night, or bounce the sun out to keep it cooler inside.
For cold weather, floor insulation is also important. Because it already has a special floor as a wheelchair van, I wasn’t able to do this without losing the ability to bolt the interior structure to the floor. Since I actively try to avoid cold anyway, this compromise was fine. If you’re a snow bunny, though, insulate everything, especially the floor because cold sinks. If you’re parked somewhere for a while and stealth is not a factor, you can even add skirting between the ground and the body of your van to trap the air under there and prevent it from getting as cold as the surrounding area. I haven’t tried this, but friends who have done this tell me it works well.
Heater
We’ve covered how to keep the heat in. Now let’s talk about how to generate more of it. These are the three most popular options.
Mr. Buddy Heater

This is one of the simplest ways to heat up your van, garage, or pretty much any other space. It’s self-contained. It runs on those small green propane bottles, or you can get a hose to run it off a larger tank. Many van lifers use a Mr. Buddy heater because it’s fast, easy, and relatively affordable at about $100. If you need a lot of heat right now, this is a good choice. Turn it on and it gives you a fast blast of heat (9,000 BTU). Wake up on a cold morning, crank it up, and you’ll be toasty in 10-15 minutes.
There are also some issues with it. Build quality gets mixed reviews. It can sometimes stop working, especially if things get clogged up inside (you absolutely must use a filter and low-pressure regulator if you run it off a non-self-contained propane tank). That fast blast of heat uses a lot of propane. You may not have the necessary clearances in front of and around the heater if you want to use it in a smaller space like a car or SUV.
The Mr. Buddy heater also shares the problems that any propane heater has. It’s a damp heat, which can cause condensation inside your vehicle, particularly if it’s not well insulated. Most importantly, it’s using the oxygen inside your vehicle to generate heat. You also need oxygen for yourself, for that basic function known as “life.” You MUST open a window a little bit to let fresh air in and keep the oxygen level up. A carbon monoxide detector is a must to warn you if you need more fresh air inside. Of course, opening a window when it’s cold somewhat defeats the purpose of warming up the inside. The heater is certainly powerful enough to offset this heat loss, but it would be more efficient if it didn’t have to.
Olympian Wave 3

I chose the Olympian Wave 3 for myself. Like the Mr. Buddy, it’s a propane catalytic heater. That means there’s no flame, though it does get hot, and you need to maintain certain clearances around it for safety (making it unsuitable for small spaces like a car). While the Mr. Buddy is a fast blast of heat, the Wave 3 is a slow burn. My nightly routine involves putting up my window insulation, turning the Wave 3 on its low setting (1,600 BTU), and running it until I go to bed. In the morning I crank it (3,000 BTU) until the inside of the van warms up. It doesn’t warm it up as quickly as the Mr. Buddy would, but it’s far more efficient on propane.
I’ve had mine for two years (I first bought it for my no-build van build) and I’ve had zero problems with it. In fact, I bought the optional set of legs for it when it was in between vans, and it helped keep us less cold while building this van during a cold New Hampshire winter. (The Mr. Buddy is self-supporting).
The biggest disadvantage is it’s more expensive than the Mr. Buddy, at about $365. I’m quite sure mine cost less, but that was two years ago. It’s also pretty hard to find one of these as I’m writing this in January 2022. Blame supply chain issues — everybody else does. The Wave 3 also suffers from the same propane-specific disadvantages as the Mr. Buddy. You still need to open a window. Since it burns less propane, condensation isn’t as much of an issue, though it could be.
Diesel Heater

Since I bought my Olympian Wave 3, there is a new contender in the arena: the cheap Chinese diesel heater. This is just one of countless options available on Amazon these days. You can get a self-contained unit like this, or one with separate components, some of which live underneath your van, which can be good if you want to save interior space. Don’t worry if you don’t have a diesel engine. You can use a small plastic jug that holds a few gallons of diesel, which will last you a good long time. When you run low, simply refill it when you get gas.
The primary advantage of these heaters, besides the price, is that the combustion process uses air from outside your vehicle. The integrated heaters draw air in from the outside, and the component heaters place their combustion chamber under the vehicle. You can close your windows nice and tight and not worry about running out of oxygen. It’s safe to let it run all night while you sleep. They typically come in either 3 kilowatt or 5 kilowatt versions. The smaller one should be more than enough to heat a van. Consider a larger one for an RV or trailer.
There are two disadvantages to these heaters. The first is that, unlike the propane heaters I’ve mentioned, they require electricity. If you already have a decent battery system or design yours with this usage in mind, this isn’t a big deal. Just keep in mind that you’re going to be mainly using this during the winter when days are short and you’re going to be getting your minimum amount of solar charging.
The other disadvantage is the inconsistent quality of these heaters. This is why they’re so inexpensive. Manufacturer support for them is virtually nonexistent. Bob Wells had a great suggestion for going this route: buy two, and keep one either as a replacement or for spare parts! Because of course the one time your heater is going to fail is on the coldest night of the year.
You should also be aware that they are not designed to work at higher altitudes above 7,500 feet. The thinner air messes up the air/fuel ratio, causing problems with combustion.
Despite their disadvantages, if I was building a home on wheels today, this is probably the option I would choose. I’d also follow Bob Wells’ suggestion, and make sure I have a backup.
Other Options
While these three are the most popular, there are other ways to heat up your van.
High Quality Gasoline or Diesel Heater

These are the units that the Chinese copied in order to make their more affordable, lower-quality versions. Look for brands like Webasto or Espar. They cost well over $1,000, but they are the Cadillac of heating systems. They’re well built and extremely reliable. You can also get heaters that burn either diesel or gasoline and plumb them directly into your vehicle fuel tank. That way you don’t have to run a separate fuel for your heat. Vancity Vanlife has a gas Webasto heater, and even in Canada, he reports no significant change in how quickly his gas tank drains when he’s using the heater.
Even the quality units like these suffer from the same altitude limitations as the cheaper Chinese units. That’s a limitation of the overall design of these heaters and not lower quality construction.
Wood Stove

People have used wood stoves for heating since long before vans were invented. The theory is still sound, and some people actually use wood stoves in their vans. The biggest issue is the space they require, both for the stove itself as well as around it to not overheat parts of the interior. It also requires a chimney. On the plus side, it simply takes wood for fuel, which is cheap to get or free if you’re in a forest. They’re extremely efficient since once the stove itself warms up it radiates heat for hours, even after the fire inside is out.
Passive Solar Heating

There’s one other way to heat your van that’s already built-in: passive solar. As much of a problem as it is to keep sun and heat out of the van in the summer, you can use this to your advantage in colder weather. I’m parked facing the southeast. When the sun comes up, I remove my windshield cover, letting the sun in and heating up my van. Before long I can turn off my propane heater, as the power of the sun is enough to maintain a comfortable temperature inside. I also take down some window covers on the passenger side to keep collecting the heat as the sun moves across the sky.
Since I have a former wheelchair van, I have windows on all sides and can open and close whatever I want no matter what direction I’m pointing. But you can do exactly what I’m doing even in a windowless cargo van. Every van has at least a windshield and side windows in the doors. I honestly don’t find I need any more than that.
Layers and Layers

Of course, you can’t take advantage of passive solar heating at night, nor is it safe to allow propane heaters to run while you’re asleep. The answer here is to simply layer up in bed. Wear warm pajamas. Wear socks. Even wear a warm hat if you need to. Huddle under multiple warm blankets. Have a good sleeping bag rated for low temperatures handy. If it’s particularly cold you can crawl inside. At other times, you can unzip it and use it as yet another warm layer on top of you. Flannel sheets are also more comfortable when it’s cold.
There are also 12-volt electric blankets available, designed specifically for use in a car. These work, but you have to be careful about how much electricity you use, especially if you let them run overnight while you sleep.
Snuggle a Pet

I’m only half-joking. Cats and dogs have a higher body temperature than humans. If you can get them to snuggle you under the blankets, that’s one more heat source you have in the bed with you. You’re warm, they’re warm, and everybody wins.
I suppose you could snuggle a human as well, but sometimes that gets complicated.