Three things are crucial to a good night’s sleep: shelter from the elements, a sleeping mat and a good sleeping bag to keep you warm.

As with most outdoor products, when it comes to selecting a sleeping bag there’s a confusing array of options. But as it often does, knowing what the intended use is for your sleeping bag makes narrowing down the selection much easier. If you’re planning on attempting to climb Mt Everest, you are going to need a top of the range goose-down sleeping bag, while if you’re just planning to do a bit of fishing in northern Australia you are only going to need a lightweight bag to keep you comfortable at night.

It’s important to realise that no sleeping bag can cover every sleeping scenario. Selecting a sleeping bag is all about compromise. If you like to go snow camping in the High Country in winter and also bushwalk in the middle of the Australian summer you’re going to have to buy two different sleeping bags, otherwise you’ll be uncomfortable in one or both situations. But if you aren’t going to camp anywhere too cold (like snow camping), then it’s possible to get by with a good all-round sleeping bag that will keep you comfortable for most of the year. An all-round sleeping bag will mean you have to make some compromises in temperature extremes, for instance, in winter you might have to wear some extra clothing or, in summer, zip the bag right out and use it like a doona.

There are a number of crucial factors in sleeping bags that affect their performance:

The Type of Insulation

The type and amount of insulation in a sleeping bag is probably the single most crucial factor in the warmth of a bag. The lightest, warmest material for insulating a sleeping bag is down, with goose down generally being considered superior to duck down. The quality of down is rated according to how well it ‘lofts’ or expands, trapping warm air – the higher the number the better the down. While it is extremely light, warm and packs to a smaller size than any other insulation, down has a few disadvantages: it’s useless when wet and it’s expensive. However, provided you take care with your sleeping bag (and you aren’t a paddler) it’s very rare for sleeping bags to get wet, while a down sleeping bag properly cared for can last a really long time, making it a good investment.

The other popular insulation material is various kinds of synthetic fills (usually made from polyester). While the technology in synthetic fills is improving all the time, in respect to weight-for-warmth, synthetics do not perform as well as down. However, synthetic sleeping bags will keep you warm even when damp. Synthetic sleeping bags are also much cheaper, although they are said not to last as long as a well cared-for down bags.


The construction of a sleeping bag is another important factor. Top-of-the-range down sleeping bags will have complex baffle structures to hold the down where you need it, while many bags also incorporate special barriers that reflect radiant heat. A lot of sleeping bags are also available with water-resistant outer shell fabrics. These can add to the warmth of a bag, and are worth considering if you like to sleep out under the stars, although they won’t keep you dry in anything but light rain as they are not seam-sealed.


The shape of the sleeping bag is another big determinant of warmth. Narrow mummy-shaped bags are the most efficient as there is little dead space to heat with your body warmth. On the other hand, mummy-shaped bags don’t allow much wiggle room compared to a more rectangular shaped bags, which most people find more comfortable to sleep in. Zips also affect warmth. Some of the lightest, warmest bags don’t have full length (or any) zips. However, having zips makes the bag more versatile, as a full length or half zips allow you to vent the bag when you are too warm (which is quite often the case in Australia).


People vary a lot as to how ‘warm’ or ‘cold’ they sleep. Generally women need a warmer sleeping bag because they have less body mass, but some men are also ‘cold’ sleepers. Often women’s sleeping bags will have a bit of extra down or insulation. Most sleeping bags also come in women’s size, which are shorter (so you don’t have to heat any dead spaces in the bottom of the bag).


Sleeping bags are often given warmth ratings, but it is worth taking these with a pinch of salt as everyone sleeps differently. It is also important to realise that often these ratings are survival rather than comfort ratings. So, for instance, if a bag is rated to -15°C, it may not mean you will be toasty at -15°C, rather you will survive the night – speak to a knowledgeable salesperson to establish what the ratings refer to so that you don’t get caught out.


If you can afford a down sleeping bag, it’s hard to beat the combination of weight-for-warmth, packability and longevity. While synthetic bags outperform down sleeping bags in the wet, generally it’s less likely for sleeping bags to get wet, particularly if you take care to pack it in a dry bag. The main reason to choose a synthetic bag is because they are much cheaper – if you are on a tight budget synthetic bags are an excellent choice.

As a general guide for down sleeping bags, if you are planning on going above the snowline in Australia, look for a sleeping bag with a minimum of 650 to 700 grams of down. If you are looking for a good all-round sleeping bag for south-eastern Australia, look for something in a semi-rectangular shape, with full-length zips and around 500 grams of down. The full length zips mean that you can open it right out during the warmer months, while when it’s a bit colder you can always put on a few extra layers of clothing inside the bag. If you are only planning on camping in warm climates, you can probably get away with 350 grams of down.

Finally, don’t forget that any sleeping bag needs to be teamed with a sleeping mat to insulate you from the ground. Even the best sleeping bag will struggle to keep you warm if you’re sleeping directly on the ground.


A well-cared-for sleeping bag can last a very long time. There are a few simple things you can do. It’s always best to use a liner; to keep the bag clean and stop oils and dirt from damaging the insulation. Sleeping with a liner (silk or silk-cotton blends are best) will also keep you a bit warmer.

Try to avoid washing a down sleeping bag, as it will degrade the down. If you do decide to wash it, follow the care instructions carefully and use an appropriate detergent (or get it cleaned professionally).

Finally, don’t store your sleeping bag compressed in its stuff sack. Keeping the bag compressed is bad for the down and will affect its ability to loft. Most good quality sleeping bags will come with two storage sacks – one a stuff sack and the other a large cotton bag for storing uncompressed at home in a cupboard.

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