Is your sleeping bag struggling to keep you warm in the winter months? Do you remember it being warmer – does it seem to have lost its warmth over the years? Or maybe you have a sleeping bag that’s better suited to the summer months and you’re about to head out in winter and don’t want to buy another sleeping bag? If this sounds like you, then read on for our 5 toasty tips for making your sleeping bag warmer.
Brrrr, winter camping can get positively arctic if your sleeping bag isn’t warm enough! Image: Sea to Summit
Here are a few tips on how to get more warmth out of your sleeping bag:
1. Wash your old sleeping bag
If your sleeping bag is on the ‘well used’ side and doesn’t seem to be as warm as it once was, you may need to give it a good wash. Over time the oils from your skin, together with moisture caught in the filling, can cause the stuffing to clump together which prevents it from ‘fluffing up’ to keep you insulated and warm.
The filling in the sleeping bag needs to puff up and expand with air which then traps the body heat of the person sleeping inside. Washing your old sleeping bag will clean the filling and enable it to fluff up more effectively, thus trapping more warm air and increasing the insulation between the person inside the bag and the cold air outside.
Avoid adding extra blankets on top of your bedding as the weight will crush the filling, rendering it ineffective for trapping the air. Use them beneath you or under your mat instead.
Wash your sleeping bag to restore its warmth.
How to wash your sleeping bag:
- Put your sleeping bag in a pillowcase to protect the thin outer material from tearing.
- Using a front loader, wash your sleeping bag on a warm, gentle cycle. (Remember to use Down Wash if you have a down sleeping bag.)
- Dry your sleeping bag in a large tumble dryer on its lowest setting. Place a few tennis balls inside the dryer as these will smash into the sleeping bag which will break up the filling and fluff it up again.
- If you don’t have access to a dryer, you can dry the sleeping bag on the clothesline in the sun. But every half an hour or so, beat it with a tennis racket to break up the filling.
In an ideal world, you would have a sleeping bag for every season. But in reality, you can make one sleeping bag a lot more versatile with a few of these hacks. Image: Sea to Summit
2. Add a thermal liner and hot water bottle
If your sleeping bag isn’t rated low enough for the conditions you’re using it in, or if you’ve discovered you’re a cooler sleeper, consider adding a silk, cotton, or fleece liner rather than purchasing another sleeping bag.
There are many different liners on the market, with our favourite being the cotton and silk versions produced by Sea to Summit. A thermal liner is made of the same material as thermal underwear and is specifically designed and rated to boost the warmth of your sleeping bag.
By adding a liner to your bag, not only will you have a great combination for winter, but you can still use the sleeping bag on its own in average conditions, and then just the liner on its own when it’s really hot! A removable liner also keeps your sleeping bag cleaner, and thus, your filling in better condition.
If you’re heading away for a particularly cold weekend, it may be worth packing a good old fashion hot water bottle as well. Or you can use a regular water bottle, just make sure it has a quality seal so it won’t leak and you don’t want the water too hot. Sports style bottles aren’t a good idea but ones like a Nalgene or 360 Degrees Stainless Steel drink bottle work well.
Just heat the billy before bed and pour the hot (not boiling) water into your hot water bottle, then tuck it into your sleeping bag with you for some seriously snug comfort. Or even better if you prepare it ahead of time so you can pre-heat your bed before hopping in!
Layer thermals under your clothes while you sleep. Image: Sea to Summit
3. Wear thermals
Thermal underwear is the warmest set of pyjamas you will ever need when camping in cold conditions. Known as a ‘base layer’ they will trap warmth directly against your skin and make a very big difference to your comfort in cold conditions. Layering clothes on top of your thermal base layer will trap air between the fabric and keep you warmer than adding a single thick layer of clothing.
Make sure you add your layers and warm up by the campfire well before lights out so the heat has time to build and is easier to maintain since it will be trapped inside with you inside your sleeping bag once you do hop into bed.
Keep your extremities warm on a cold winter’s day. Image: Sea to Summit
4. Put on a beanie and socks
Humans lose about 30% of their body heat through their heads. By wearing a beanie to bed, or tightening the hood of your sleeping bag, you can trap more warmth – just keep your mouth and nose free so you are not breathing into your bag which creates moisture throughout the night.
When your body gets cold, it takes blood away from the extremities such as your feet and hands, in order to keep it around your vital organs. By heading to bed with warm socks and gloves, you can keep your feet and hands warm and your body will keep the blood flowing to them, making for a better night’s sleep.
Tuck into a large dinner before bed. Image: Coleman
5. Eat a big dinner!
Your body will use a lot of energy to digest your dinner. All this energy will produce heat and keep you warm. By eating a decent sized dinner, and making sure it’s full of low GI carbohydrates, your body will keep burning fuel all through the night.
Two-minute noodles give you enough energy for 2 minutes. On the other hand, a big bowl of spaghetti bolognese will ensure a good night’s sleep! Just don’t eat too much, and go easy on the garlic or you’ll be awake with indigestion! And contrary to popular belief, if nature calls during the night, you are better off surrendering to it as holding on will override your kidney’s signal to your brain and through a chain of technical temperature regulation measures, our bodies feel colder when our bladder is in need of relief.
Hopefully, this advice will help keep you snug while you sleep. Image: Sea to Summit
Keep warm on your next adventure
No matter how old or the quality of the sleeping bag you own, these tips will help you get the best performance out it, but a couple of other points worth noting are that your sleeping bag is part of a whole sleep-system, meaning that your choice of mat will also influence how cold or warm you’ll be throughout the night.
An airbed is not one to keep you warm as the air within the mattress will stay cold. Instead, choose a closed-cell foam or filled mat to trap air and help insulate. Sleeping inside a smaller tent that’s double-walled (ie. using a fly) and having decent ventilation to reduce moisture build-up are also tips worth bearing in mind.
Here’s hoping you can get a good night’s sleep even on those freezing cold winter nights and you won’t have to resort to the ancient Native American method of creating a hot rock bed or the extremely dangerous (and not recommended) tactic of using a heater inside your tent!
Do you practice any of these tricks? Got any more to add? Comment below.
About the writer...
G’day! My name is Dave and there is nothing I enjoy more than getting out in the bush and enjoying the challenge and serenity of travelling around this beautiful country of ours.
After 6 years working as an Outdoor Ed Instructor, I’ve joined the team down at Snowys to help others get geared up and head to the outback!
As an enthusiastic photographer and freelance writer for 4WD Action magazine, I love to get out and capture God’s stunning creation and share it with the world.
After getting married at the end of 2010 and having our first child January 2012, I’m looking forward to seeing more of this beautiful country with my family.
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I had a freezing night on the Overland Track and heeded some advice from the ranger on the second night. He suggested vigorous activity just before bed, then jumping inside with only a thinnish layer, and trapping your body heat in. The second night was much better.
I know people who swear by this method as well, Maggie! Extra layers don’t equal extra warmth, and with the right gear, less is more. Cheers mate
Thank you for your excellent, unique and original article. I’ve tried to locate clear information on this topic many times. You have helped make this interesting as well as clear.
Cheers David!
Great article, but just to clarify something, humans do not lose 30% of their body heat through their head (or feet , as many people believe). It is an urban myth, the rate of heat lose is roughly the same for all parts of the body. The head represents 10% of your body, therefore it loses 10% of your body heat
We certainly feel warmer with something on head, which I guess is half the battle of keeping toasty!
That’s really interesting Chris! Cheers mate
How do I wash my sleeping bag in a pillowcase? ??♂️
G’day Chris, if your sleeping bag is too large to fit inside a pillowcase, you could turn it inside out (zipped up) and wash on the delicates cycle in your machine. Alternatively, if your bag is filled with down, you might be keen to have a read of this blog for a few extra tips…
https://www.snowys.com.au/blog/wash-down-sleeping-bags/
Cheers
Put it in a duvet cover if it’s to big for a pillow case
Bought my goose down sleeping bag before heading off for a year’s backpacking around Europe in 1991. I cost me a fortune at the time but was bought for its minimal weight and size, as well as warmth.
It’s proved one of the best investments I have ever made in bedding or camping gear. It’s accompanied me across 5 continents and kept me warm in some truly remote locations.
It has been well used as a sleeping bag but just as regularly, unzipped, as a “travel” doona. I find the latter works if I do not need the full extent of its -4 mummy style insulation.
I’ve always used it in conjunction with a liner. Sometimes it wears a doona cover, when it gets used as such and gets stored, as per the origiinal instructions, unpacked on a coat hanger, so it is able to loft, rather than remain utterly compressed.
If using it as a doona, I do have to make allowances for its mummy shape, but, I’ve always made it work.
Stuffing it into its compression bag remains hard work; however compression bags have come a long way since the 1990s and I should probably investigate shouting it an updated compression bag, that is a bit more user friendly!
It is about to receive its first wash, before it moves into my camper van, to continue to serve me.
Guess my trusty sleeping bag is living proof that investing in quality gear and looking after it accordingly, is really worthwhile!
I have one I bought to take to Nepal in 1988 – I still get excited every time I use it and it is still in fabulous condition. Heavy, I suppose by today’s standards, but I love it and it was worth every cent. We use it as a doona in the camper as well. Mine is a Salewa I think.
I made the freezing mistake in getting too cold on my motorcycle and not taking off the waterproof liner and pants before getting into my -20c down sleeping bag in combination with a Exped winter 9cm down mat, as a result the bike gear prevented any warmth I could generate from warming the loft in the bag. It got down to only -3 and I was so cold all night thinking that my 25 year old down bag has lost it’s warmth.
The trick after some research is not to insulate the body from the bag but to allow body heat to warm the bag loft which traps the heat, and give your down bag a good shake when getting it out of the compression sack.
It’s a shame you had find that out from a freezing cold long night, but at least you know how to stay warm for the future, Rob – cheers!
Boil the kettle and fill up a hot water bottle, perfect for camping
Can’t go wrong with a tried and tested hot water bottle, Linda! Cheers.
A good sleeping bag will be EN rated but many people do forget that the EN testing is done with the use of and assumption that the mannequin/people are already wearing medium weight or winter weight thermals plus gloves and socks and a beanie.
So while adding warm clothing will boost a cheap bag doing so only allows a tested bag to achieve it’s rated minimum temperature. Also as we get older we do tend to need more sleeping insulation, it’s about 5C extra needed for every decade after 30 [ the EN testing assumes a fit and healthy young adult too] so my almost 70YO body will need a bag rated at -25C if I am camping in the Outback in winter where night time temperatures can drop as low as -12C These bags are very expensive An ultra lite synthetic blanket over the top or an overquilt is a great way to extend the temperature downwards, a synthetic quilt using 100GSM insulation can boost a bags rating by up to 10 degrees
Thanks for sharing your expertise Ted, especially about how you need extra insulation as you get older as that’s something a lot of people might not know – cheers.
You can pack you’re clothes that you are wearing the next day down near your feet as well. Also you can put your feet into a bag of some kind, if allowed you can make a heat shield with some green logs & direct fire back towards your shelter I’ve done this whilst it was the middle of winter & snowing on the Barrington tops national park in a swag for three week’s.
Do not eat a big meal. Your body will divert blood from your extremities to your GI tract to digest the food leaving your feet and hands cold. Drink a decent amount of hot water/broth/tea.
Put a hot water bottle in the sleeping bag an hour before you go to sleep. Nice and toastie!
The hot water bottle trick is a classic, and it’s the next best thing when you’re away from your electric blanket Vaughan.
Putting a decent layer between you and the ground makes such a difference. Having a ground mat or anything to line the tent floor under you helps. This goes for Under blowup mattresses too. It can get SO COLD otherwise.
Insulation is everything especially in those cold winter months, Rosie. 🙂
Foam mats are great under a blowup mattress, really insulation from the cold ground.
Agree, insulate your base to prevent heat loss.
if you are using a stretcher then placing a beach towel or even spreading news paper on the strecher can make a big difference.
And don’t forget to unpack your sleeping bag as early as possible to give it time to fully loft.
You’re on the money there Chippy, especially if it’s a down sleeping bag. Cheers!
Shake it out first too!
Make sure your store your down sleeping bag outside of its stuffsack. An intellectual friend of mine has failed to heed my advice on this and keeps it in the stuffsack. Perhaps he is not so intellectual. Keeping it stored loosely or fully stretched out under a bed means the down is more likely to retain its memory of being able to expand fully enabling it to loft more therefore providing greater warmth. If kept in a stuff sack the down and feathers can get crushed to the extent this memory is lost with minimal lofting and decreased thermal efficiency of the bag.
Well done to Snowys for providing these helpful articles and handy hints.
A down bag? Kept in its stuff sack? Definitely not the best way to do it that’s for sure!
Thanks for the compliment, we’re so glad you’ve enjoyed the tips in the article.
My sleeping bag is a good quality high performance one which packs down light and small for kayaking trips but in the freezing cold of the outback it was found wanting – so I bought an el cheapo $40 bag from Target – (packing small not a problem for the Prado roof rack), and I put my good bag inside the cheap one – that extra layer of trapped air between them working wonders – and I can open up the out side bag as needed when the nights are warmer. Predawn ice on the outside of my little tent but snug as a bug inside.
There is nothing better than feeling snug and warm when it’s icy cold outside, thanks for sharing your hack for making your sleeping bag warmer Trev.
These are all good tips. It is important to put new socks on at bed time, so wear tomorrow’s socks. This is because socks take up moisture from the feet and when that moisture evaporates, your feet will feel cold.
That’s an important distinction Meredith, we hadn’t thought of that but you’re right – clean socks are the way to go!
The dog is a great foot warmer if you have it with you! Haha!
A cute companion is almost better than a hot water bottle on a cold winter night 🙂
Foot warmer, sure mine tend to snuggle next to me. I was up in the Rockies in Colorado early spring, snow still on the ground. My two Samoyeds/with packs were more than content to be in the tent with me. They would typically sleep on both sides of me and I was as warm as sleeping at home.
I did leave the tent unzipped a bit cause of all the breathing.
Something I am surprised that no one mentioned, that I saw, was a bivy sack. I got one long ago so I did not have to set up the tent so often. The bivy sack will help a bit on the temperature if your not in a tent.
Best tip: share your sleeping bag with a furry friend!
Touché Sam – nothing like a friendly (and cuddly) portable heater to share your sleeping bag with. 🙂
Dogs actually have a higher body temperature than humans and whippets and greyhounds, higher again than other dogs. My whippet beats a hot water bottle and keeping him warm is as vital as keeping myself warm!
With that big meal, drink plenty of Port to stave off the cold, along with whatever other preferred tipple you may prefer.
As a bonus you may get to miss the early morning frost as well.
Assuming you made it to your sleeping bag.
The next day will be horrendous but you will sleep undisturbed.
Too right Glenn – a cheeky glass or two always helps send you off to sleep on a cold night!
Number 1 tip to keep warm is take your partner to bed with you. ????
Agreed! 😀