How to stay warm in a sleeping bag: Pro tips

Megan Smith
 min read

How to stay warm in a sleeping bag:

How to stay warm in a sleeping bag: Pro TipsThis post will tell you what won’t work, what will cost you money, what won’t and the bare essentials.

Using a sleeping bag in (really) cold temperatures can be very pleasant, provided you don’t get cold!

After reading these tips on how to stay warm in a sleeping bag, check out our tips to buy the top sleeping bag for big guys.

How to stay warm in a sleeping bag: Introduction

Here are a few tips to make sure you have a good night’s sleep when bivouacking under the stars or in a tent.

We have classified the tips for not being cold in your sleeping bag in 4 categories:

  • the myths
  • tips that will cost you some money
  • tips that are simple and free (or almost)
  • tips that are essential

How to stay warm in a sleeping bag


  • Don’t drink a glassful of whisky (or other spirits): alcohol dilates the veins
    • In the long term alcohol will increase the feeling of cold by an increased loss of heat.
  • Don’t start your stove in an enclosed space (tent): risk of death due to CO fumes.
  • Don’t wrap your sleeping bag in a survival blanket: it creates condensation, and you’ll shiver all night long.
  • Don’t sleep naked: This was true decades ago, when we only had wet cotton to wear.
    • Even if you’re hairy, merino wool underwear will be much more suitable.
  • Don’t stuff yourself with food during the evening meal: you’ll sleep badly (stomach aches).
    • Eating too much will use up your body’s energy for digestion instead of heat.
  • Don’t use a silk bag sheet: contrary to popular belief, silk is not warm. It actually cools the body.
  • Don’t pile up all the layers of clothes we have: Too much will prevent the sleeping bag from warming up.

Slight expenditure

  • Use a real thermal bag. There are light, warm thermal sleeping bag sheets which improve the temperature of your sleeping bag considerably.
  • Use soft hot water bottle in your sleeping bag: the old remedy that still works.

No expenditure

  • If you sleep in a tent, tighten the outer fabric so that it does not touch the inner fabric (insulating air layer).
  • Do not hold back from urinating. Besides stomach kidney pain, holding back consumes calories.
  • Do not overdress in your sleeping bag.
  • Merino wool underwear is sufficient (long sleeve t-shirt, 3/4 or long tights, socks, hats, gloves).
  • If we are too hot, we sweat, we wet our sleeping bag and we get cold.
  • Build a small wall to protect against the wind (stones, embankments, snow, etc.).
  • Besides wind insulation, it increases body heat (just don’t sweat).
  • Do some exercises before going to bed (squats, push-ups, reels, jumps, etc.)
  • Keep your mouth and nose out to avoid creating condensation inside.
  • If possible and permitted, build a fire nearby.
  • Beware of wind and twigs that can ruin your tent, your sleeping bag causing it to lose feathers, etc.
  • Eat a light, digestible meal in the evening before going to sleep. Eat enough, but not too much, and eat hot if possible to conserve energy
  • Keep the (precious) warmth and don’t wait get cold to dress up.
  • Drink something warm before going to bed: sweetened herbal tea for example.
  • If there is too much space in the loins or abdomen, put an open down jacket under or over you.
  • Close the sleeping bag well to avoid cold draughts: zipper, shoulder collar, elastic tightening of the hood.
  • Remove the day’s sweat/grease: even if it’s cold, cleaning or washing ensures better skin breathability.

The essentials

  • Cover the extremities (hat, socks, and gloves).
  • In very cold weather, the body will send heat to vital organs (chest and brain), to the detriment of the extremities.
  • Be careful not to get your sleeping bag wet on a rainy day. Use garbage bags, plastic bags, waterproof bags, etc.
  • Make sure his sleeping bag is the right size.
    • A sleeping bag that is too small will make your feet and head feel cold.
    • A sleeping bag that is too large results in more volume to heat.
  • Wear merino wool underwear (the same as the ones used during the day).
  • Sleep on an inflatable mattress or a great camping bed. Much of the cold felt comes from the ground.
  • A good quality mattress allows us to insulate ourselves against the cold of the earth.
  • Opt for the best type of sleeping bag. Not necessarily the warmest, or the most expensive, but one that adapts to our needs (a down sleeping bag in dry weather, synthetic in wet weather, etc.).

How to stay warm in a sleeping bag: Conclusion

Sleeping outside with a sleeping bag is great but you don’t want to feel cold and chances are it will get dirty so you will definitely have to wash the sleeping bag thoroughly when you get back home.

If planned well, you can ensure that you make your trip in the best possible conditions.

Most of the time, simple tricks based on common sense allow you to go camping.

It would be a missed opportunity to do otherwise and suffer the cold unnecessarily.

Other posts related to sleeping while camping:

About Megan Smith

Megan has been fighting overweight and her plus size since her teenage years. After trying all types of remedies without success, she started doing her own research. Megan founded Plus Size Zeal to share her findings. She also developed various detailed buying guides for plus-size people in order to make their lives easier and more comfortable. Read More