Five tips to choosing the perfect sleeping bag

Staying safe and dry is the most significant comfort factor when travelling, and staying warm and well-rested is a close second. The latter comes down to your bedding, and when camping that often means sleeping bags.

Sleeping bags are the bedding of choice for many RVers, no matter their method of transport; even for caravanners, who may need to leave their rig behind in order to get off the beaten track.

And, given the importance of a good night’s sleep, making the right choice is important.

THE BASICS

Choose a sleeping bag that is comfortable and appropriate to your circumstances. Sleeping bags come in many shapes and sizes, so make sure you have room to move around. The most common shape for ‘vehicle camping’ is rectangular, and that’s what we’ll concentrate on here.

Using an unzipped bag as a single layer, like a doona, can be effective as long as it’s not too cold and you have good insulation underneath. However, if you prefer to use it like this all the time, it’s probably better to consider an actual quilt.

Sleeping bags are rated by the lowest temperature at which they will keep a ‘warm sleeper’ comfortably warm, but be cautious. There is no agreed standard on these ratings and manufacturers apply their own evaluations. When choosing a bag, add 10ºC to the coldest temperature you expect to experience.

Gender and age are also factors. Men and the young are known as ‘warm sleepers’. Women and older people typically require a warmer bag (rating 5-10ºC), as they have a lower cold tolerance.

INSULATION

The bag’s outer covering is known as the shell. It has to retain the air and warmth but also allow moisture to escape (your body exudes up to a litre of moisture per night).

To trap warmth, sleeping bags have a layer of insulation between two shells. This can be either down or synthetic. Down is lighter, longer lasting (when cared for), expensive, very compressible so takes up little room, warmer, more difficult to care for and not hypoallergenic. Synthetics are cheaper, heavier, bulkier, more easily cared for, hypoallergenic but lose their insulating capacity more quickly.

Down is the undercoating of waterfowl. It can be from geese or ducks, but not chickens, and it is not feathers, although it’s common to get up to 15 per cent feathers in a down mix. Down does deteriorate with age, depending on care and use. The bag should be stored in a loose cover so it stays ‘lofted’. Loft may be described as fill power. The more down can expand, or loft, after being compressed, the better it is. This can be measured, and the higher the number, the better the loft, or insulating power. Around 850 is top-of-the-range.

Synthetic fillings, which are basically a tangled mesh of fibres, can be very good. They can provide more insulation than down if damp, and can withstand more rough treatment or washing. Generally, the higher the measure of grams per square metre of insulation, the better the insulating capacity, but also the heavier, it will be. The insulation is held within the shells by either stitching or baffles.

Do not add other coverings over the bag as this compresses the insulation and makes it less efficient. If you are still cold, wear extra clothing.

A neck muff – a roll of padded material around the shoulder/neck of the bag – helps to retain warmth. Hoods can be important in very cold conditions, allowing you to pull a drawstring tight around your face. A good bag will also provide a drawstring at the neck so you can tighten that opening, but ensure this slides easily.

ZIPPERS

Zippers are important. They leak heat and frequently snag on the linings, so a draft tube on the inside of the zipper will help retain heat. All zippers should be auto-lock, which prevents it opening during use.

The difficulty in Australia is that our climate can range from sub-zero to tropical, so sleeping bag choice is difficult. Either you require two bags – one for winter and one for summer – or use a dual-mode models.

Most bags have a hook and fastener tab at the top, over the head of the side zip, which retains the bag around your shoulders but permits you to control the inner temperature by partially opening the zip.

LINERS

We all like to think we live clean lives, but after a long day of driving or even lazing around camp, you are still likely to need a shower once a day, which may not always be possible. Even if you do, you will still lose fluid and a little body odour into your sleeping bag, and it will gradually accumulate.

To minimise this, use a liner, which is a lightweight inner bag that you can wash after each trip. A liner will also add to the bag’s thermal efficiency.

CARE AND MAINTENANCE

Packing your sleeping bag is important. Avoid rolling the bag tightly for storage if you can. This compresses the insulation and ruins its thermal characteristics. If possible, shove the sleeping bag into its stuff bag randomly until it’s all inside. This maintains a random packing of the insulation which keeps it performing at its best.

When you get home, wash your liner and air your bag (out of the sun) for at least one or, preferably, several days. Store the aired bag loosely so it isn’t compressed. On a long trip, you may feel your bag is losing its performance, but this is more likely due to accumulated moisture, so give it an occasional airing.

Sleeping bags can become dirty and can require washing. This should be kept to a minimum as it can cause the loss of loft in down and the compaction of fibres in synthetics. Look for instructions with your bag and follow them closely.

Rules of thumb to assist your sleeping bag perform: eat a full meal before bed to ensure your body has the fuel to produce heat; remove tight or restrictive clothing (including bras and watches) to encourage blood flow; have good insulation beneath your bag, especially around your feet where hard points can flatten insulation; camp among or near trees as they trap warmer air; if possible, have a tent partner with whom you can share heat; keep the top of your bag as tight as possible to limit heat loss; use a liner or wear pyjamas or thermals if cold; and avoid alcohol as it does not warm you up.