Warmth – an essential element
Many people tell me they won’t go camping unless the weather is very hot, as they don’t want to be cold overnight. If done right, even in surprisingly cold weather, you should be able to stay toastie-warm. The tips I listed below should help you remain warm.
Active or passive
First things first – there are active and passive ways to keep warm. Active ways to keep warm are things that generate heat and make you warm. Passive ways don’t generate heat – all they do is offer insulation, to preserve the heat your body naturally generates.
Fire (of some sort)
In the most basic form, active heat could be making a fire. (Side note: please don’t make fires when camping, unless there are dedicated facilities just for that? Fires leave ugly scars on the landscape, and goes against the most important rule for camping: Leave No Trace). Of course, fires are simply one way, and there are others, including your camping stove. Those aren’t the only options, though. You could place a tea-light candle inside a china cup. The tea-light will warm the cap, and that will give off extra heat. You should be able to do that for a short while in an unvented tent, but don’t expect lots of heat. Obviously, you need to be extremely careful with any open flame near synthetic (and therefore flammable) kit!
No, you should never use your gas stove inside your tent. Carbon monoxide poising has killed far too many people who thought they would get away with using a gas stove in the tent. If you want to cook, or make warm drinks, you do so outside your tent! Yes, even if it’s raining. Also, remember that tents are made from very flammable material, and plenty of campers suddenly found themselves without a tent, and usually also without a sleeping bag, after a flame came too close to their tent.
There are single-use hand-warmers available, often even from supermarkets. Please don’t use those? Yes, some people swear by them, but we’re in the middle of a climate crisis. The last thing we need is more single-use products, that cannot be recycled and contain lots of plastic.
There are better options available – simply search for “re-usable hand warmers”. Those are thick plastic pouches containing an over-saturated sodium acetate solution, as well as a metal disk. Clicking the metal disk caused the sodium acetate to start crystallising. During that process, it will generate a fair amount of heat that will last a few hours. Afterwards, they can be re-set for the next use by boiling them in water, until all the sodium acetate crystals dissolved again. On a cold night, you’ll appreciate several of those inside your sleeping bag! Just ensure you don’t hold them against bare skin for too long. Also consider saving a few unused pouches, in case you wake, feeling cold, at 4am.
You can get heated gilets, that run off a USB power bank. Obviously, you’ll be limited by the capacity of the power bank. You can also get USB-powered heated insoles, and I sometimes use mine to pre-heat my sleeping bag.
Passive heat is not a heat source, but a heat preservation strategy. A very simple example is your sleeping bag. The bag doesn’t generate any heat, it only traps some of your body heat. The best insulation material is feather down, but hollow-fibre synthetics come reasonably close. Hollow-fibre insulation has one enormous advantage over down, in that it dries far quicker. When down gets wet, you’re in for a cold night, so it’s important to protect your sleeping bag from wet at all times. Yes, even if it’s a synthetic bag.
It would help to understand how insulation works. Your body warms the air immediately around you. If that warmed air can escape, to be replaced by cooler air, you will start feeling cold. The idea is to trap little pockets of warm air near your skin. Fleece is really good at doing just that, but ultimately, what you’re after is not one superinsulation layer. Instead, you want lots of different layers. The more layers your body is covered with, the warmer you’ll be. My sleeping bag is really only meant for summer use, but in cold weather I use a fleece blanket as an inner. That makes a huge difference. I’ve camped in temperatures down to -7 degrees Celsius and was nice and warm in my sleeping bag.
Remember your feet! If camping when it’s cold, go to sleep wearing at least 2 pairs of socks, to help keep your toes toasty warm. Because I shave my head, in cold weather I sleep with a Thinsulate beanie on. Related, ever heard the story that you lose 50% of your body heat through your head? Well, it’s simply not true but wearing a hat when cold will help you stay warm.
Topping up body heat
Your body amazing, and is quite efficient at generating the heat you need to not only survive, but remain comfortable. Having said that, remember when getting into your sleeping bag it will be cold at first. To warm it, you will sacrifice some precious body heat. A neat way to preserve that body heat is to pre-warm your sleeping bag. There’s a great, old-school way of doing that: a hot-water bottle. Whether you use an actual rubber hot-water bottle, or just a heat-resistant flask is irrelevant. As long as it will release the heat from the hot water, and won’t leak, you’ll be fine. I prefer a flask, as water can be in short supply when camping. That way, I can use the water from the flask for coffee in the morning.
Eat a warm meal before getting into your (pre-heated!) sleeping bag, and have a hot drink, too. If you wake up from the cold, don’t ignore it! Get out of your sleeping bag, but close it up behind you. That’s to preserve the warmth it contains, for when you get back inside it. Next, make a hot drink. Topping up your body heat from the inside is one of the best ways to help remain warm. Boil more water than you need, then refill your hot-water bottle while you’re at it. When done, do yourself a favour and go for a wee. Well, you’re already out of your sleeping bag, aren’t you? Afterwards, with the tent zipped up behind you again, crawl back inside your still-warm sleeping bag. Hug your hot-water bottle, and drift off to sleep.