How to Enhance the Warmth of Your Sleeping Bag

Camping expert Jessica LaPolla runs through some easy tips for keeping your sleeping bag in tip-top shape and for keeping you extra warm on your next trip.

A hiker fluffy out his sleeping bag on a mountain summit next to his hiking partner with the sun setting over snowy mountain scenery in the background

Photo by Stefan Schlumpf, courtesy of Deuter

Nobody wants to wake up in the middle of the night in a tent in the backcountry with chattering teeth. If you’ve been there, don’t worry, there are many different ways to enhance the warmth of your sleeping bag, both before and during your overnight adventures. In this article, I’m going to run through some easy at-home maintenance tips for keeping your sleeping bag in tip-top shape, keeping you extra warm on your next trip.

Sleeping Bag Maintenance

At home, it is important to regularly assess the condition of your bag. Is it fluffed up? Insulation, such as down, only works if the loft is intact and fluffy. If your bag seems to be flattened or in need of a wash, put it in a pillowcase to protect it and send it through the wash on a gentle cycle. If you have a down bag, make sure to use a special down shampoo or wash and tumble dry it on low with tennis balls.

Does your sleeping bag have any wear and tear? Patch up any holes where stuffing could escape. When storing your bag at home, take it out of its stuff sack and leave it open and fluffed up, so that it isn’t constantly being compressed and flattened.

What to Wear in your Sleeping Bag

Now, let’s discuss a few practices to use while you are camping or backpacking. To understand how to increase the warmth of your bag, you must also understand the function of a sleeping bag. Sleeping bags keep you warm by trapping and radiating your body heat. This is why wearing dry base layers or long underwear inside your bag is most effective. Opt for wool over synthetic fabric; it will keep you warmer and it doesn't hold onto odor, so you'll stay smelling fresh for way longer. Wearing extra clothes could compress parts of your bag, reducing the insulation qualities. It could also make you sweat. Wearing damp clothes can trap moisture and compromise the insulation of your bag. Make sure your base layers are well fitted, but not too constricting. Clothes that are too tight may restrict blood flow, making you colder. Keep your extremities warmer by wearing good socks and if needed, gloves.

Maximizing the Efficiency of your Bag

When you set up camp and you pull your sleeping bag out of its compression sack, let it fluff up completely before crawling inside. If your bag has a continuous baffle, you should shake it out to distribute the stuffing evenly. If you’re really in a cold pinch, shake the bag so that more of the insulation distributes around your core. This will help keep you warmer at night. You might think it’s a good idea to add blankets over top of your sleeping bag, but this should be avoided. Putting any blankets or jackets over your sleeping bag will compress it and it will lose some of its ability to insulate and keep you warm.

Looking down at two sleeping bags, a yellow and red one, and out at the snowy sunset mountain scenery beyond

Photo by Stefan Schlumpf, courtesy of Deuter

More Tips to Maximize the Warmth of your Bag

Avoid Heat Escape

Some sleeping bags, like mummy bags, have a hood, and usually if they are rated for cold temperatures, a drawstring. Close the bag around your head and face as much as possible to minimize any cold air seeping in. If your bag doesn’t have a hood that you can draw closed, wear a beanie or a balaclava to keep the heat from escaping from your head. Make sure that the zipper on your bag is all the way closed to minimize any draft.

Create Warmth

Another useful trick to make sure you stay as toasty as possible is to use a hot water bottle. You can fill your water bottles with boiling water before bed and put them in your sleeping bag. Put them inside of a dry sack or bag in case they leak. If you’re cold camping, this will ensure you have plenty of unfrozen water for the next day as well. If you’ll be camping in freezing temperatures, make sure you bring wide-mouthed bottles; these are less likely to freeze over.

Eat

Make sure to eat a calorie and fat-rich dinner an hour or so before bedtime. This will give your body the energy it needs to stay warm. Eating right before you go to bed though could actually make you colder, as your body will be using energy to digest food at first, not keep you warm.

Sleeping Pad

Use a closed-cell foam sleeping pad instead of an air pad, or use both. Just an air pad will not provide you with enough insulation to keep you warm. Just think of a time you slept on an air mattress. Even in warm air, it can cause your temperature to drop. Good sleeping pads will not only make you more comfortable but can keep you warmer.

Tent Selection

Make sure your tent is appropriate for the season in which you are camping. A three-season tent is not meant to withstand harsh cold or windy climates, and in extreme situations, could actually suffer damage or be destroyed by weather conditions. Don’t zip your tent completely, even when it’s cold. That’s right, it may sound counterintuitive, but unzipping a small portion of your tent will allow for ventilation, decreasing moisture in the tent and allowing you to stay much warmer inside of your sleeping bag.

Pee (Before Getting in Your Sleeping Bag)

Pee right before you go to bed. This will ensure that your body is not wasting energy on holding your pee at a certain temperature, and it also prevents you from having to leave your bag or tent in the middle of the night. If you regularly wake up in the night to pee, keep a pee bottle in your tent so that you don’t have to go outside. Empty it away from camp the next morning.

Exercise

This tip is not going to sound like fun, but another way to make sure you sleep warmly and soundly is to do some light exercise before you climb into your sleeping bag at night. Some jumping jacks or push-ups will get your blood pumping and your body temperature up, so when you get into your bag, excess heat will radiate off of your body and keep you warm from the start.

What if the Temperature is Way Colder than I Expected?

You set out on an overnight trip with your sleeping bag that is rated to 20°F. However, it becomes much colder than you anticipated, dropping down to about 15°F that night. Now, you’re not going to get frostbite, but you’re probably going to be chilly. There are a couple of things you can do here:

  • Thermal Sleeping Bag Liner: One, use a thermal sleeping bag liner. They are available in silk, cotton, and fleece and can increase the warmth of your sleeping bag by a few degrees. They are typically lightweight, so if you think there’s a chance that the temperature will decline, bring one along for peace of mind.
  • Vapor Barrier Liner: If you know you’ll be camping in extreme weather and it becomes much colder than you are prepared for, utilize a vapor barrier liner. A step up from a regular thermal liner, these are not very comfortable and will make you feel clammy, but they can increase the warmth of your bag by quite a bit and will keep you from freezing.

Final Thoughts

If you are looking to buy a durable winter bag for cold-weather camping and want to maximize warmth, look for a high-fill down insulation (800+) bag with a hood. Synthetic insulation can be good for wet or damp climates but typically is not as warm as down. Ideally, make sure it has a box or continuous-baffling system and, to really go all out, select one with an overstuffed foot box to keep your toes toasty.

Whether you’ll be camping on a mild summer night or in sub-zero Arctic temperatures, be prepared by taking care of your sleeping bag. Make sure you take a sleeping bag that is rated appropriately for the expected temperatures, and bring a liner if you expect it could be colder. Follow these tips and you’ll stay cozy and warm on your next trip. And if you have any questions on finding the right sleeping bag for your next adventure, reach out to me or one of my fellow Camping experts here on Curated for free, personalized advice. Happy camping!

Like this article?
Share it with your network

Written By
Jessica LaPolla
Jessica LaPolla
Camping & Hiking Expert
Hi there! I have always had a deep love for the outdoors, having grown up on my family's horse farm in New Jersey. I began hiking and camping at a young age and started backpacking as a young adult. I now enjoy taking weekend backpacking trips with my dogs and rock climbing with my partner. This yea...
View profile

Curated experts can help

Have a question about the article you just read or want personal recommendations? Connect with a Curated expert and get free recommendations for whatever you’re looking for!

Read Next

New and Noteworthy