Choosing The Right Sleeping Bag
We all know how important it is to get a good night's sleep, and none more so than after a long hike on the fells. So, whether you are camping wild on the hills or enjoying the facilities of a well run campsite and bar, a good quality and warm sleeping bag will pay dividends in aiding recovery for the next day.
In this guide we will look at:
- Selecting the Correct Comfort Rating
- EN Ratings
- Shapes and Features
- Storage and Care
Selecting the correct comfort rating
Sleeping outside at altitude will be much colder than at lower levels, and so choosing a suitable sleeping bag will be defined by the worst case scenario of your planned camping location, and by the weather/temperature expectations.
You may not require a four season Down bag for summer family camping in Cornwall, but a higher rated sleeping bag is easier to vent off than trying to get warm in one that is unsuitable; if in doubt, choose a higher rated sleeping bag.
The comfort rating of a sleeping bag relates to the lowest temperature at which the bag will keep the average person warm and should be used only as a guide.
The minimum recommended temperature relates to the lowest temperature recommended by the manufacturer, but beware, do not expect a restful nights sleep using that bag at the extreme end of the temperature rating.
- 1-2 Season Bag: Comfortable down to +5 degrees C
- 2 Season Bag: Comfortable down to +1 degree C
- 2-3 Season Bag: Comfortable down to -2 degrees C
- 3 Season Bag: Comfortable down to -5 degrees C
- 4 Season Bag: Comfortable down to -7 degrees C
EN 13537 Ratings
Sleeping bags sold in the EU should now clearly display the standard EN Ratings for temperature. As with all things bureaucratic, these are not the easiest to understand, but they do provide a standard measure of temperature across different types and brands of sleeping bag.
As a baseline the clever blokes doing the testing identified that Women tend to get colder than men, given the same temperature. With this in mind they came up with 3 distinct temperature ratings:
- EN Comfort - This is the lowest temperature at which a Woman will have an uninterrupted night's sleep.
- EN Comfort Limit - This is the lowest temperature at which a Man will have an uninterrupted night's sleep.
- EN Extreme - This is a survival rating only. It shows the lowest temperature at which a Woman should avoid hypothermia.
The most important point to make here, is the EN Extreme rating is NOT a suitable rating to base your choice of sleeping bag on.
Most of the sleeping bags we sell on Webtogs.co.uk will have a graphical EN Rating chart in the description area, that looks like this:
Other important factors that may affect your overall comfort and warmth may include:
- Sleeping Mat: Invaluable item, designed to insulate the user from the ground and offer a greater degree of cushioning. Big Agnes Sleeping Mats do a great range of these.
- Tent: The air trapped in your tent will be warmer depending on how well it is insulated and draught free. Also, the smaller the tent, the warmer the tent will be. Check out the range by Vaude.
- Metabolism: we're all individuals, and our bodies react differently at night, some people are `cold sleepers', and wrap up well, while others can be `warm sleepers' and prefer to have some space to kick off the covers.
- Clothing: That comfort rating we spoke of earlier is gauged with the assumption that the sleeper is wearing both top and bottom base layers, so the amount that you wear when sleeping will greatly affect your temperature. Always a bonus too, is to wear only clean, dry clothing when crawling into your 'maggot' for the night.
- Gender: Women on average are colder sleepers than men and may benefit from using a warmer sleeping bag.
- Hats and Hoods: A great deal of heat is generated and lost through an unprotected head. Close the hood of the sleeping bag around your head for added insulation, or wear a hat.
- Hydration: Keeping yourself fully hydrated during the day will help towards a good nights sleep, as will a hot drink just before bed – just keep your torch and slippers handy!
- Sleeping Bag liner: This is a great way to upgrade the warmth factor of your bag and keep the bag clean too. Silk liners are lightweight and effective, fleece is the warmest but bulky, and cotton liners are an excellent cheap compromise.
Remember: Select your bag with the most suitable 'comfort rating' to gauge the lowest temperature for a good nights sleep.
Keeping you warm
A sleeping bag is designed to keep you warm by trapping the non-circulating air between you and the bag. Your body warms the trapped air inside and depending on the level of insulation, the warmer you will be. The less empty space there is to heat between yourself and the inside of the bag (the tighter the fit) the quicker you will warm up, and stay warm.
Sleeping bag insulation generally falls into two categories: Goose Down or man-made Synthetic fibres, and each system has its own advantages and disadvantages:
- Goose Down: A quality Goose Down bag is the lightweight sleeping system of choice for Mountaineers, serious backpackers and most certainly for those who count the grams such as expedition cyclists when the weight-to-warmth ratio is paramount. Although a quality down bag will be constructed with a durable water repellent outer fabric (DWR), this will not keep it waterproof, and a down bag will bunch-up and loose it's insulating qualities rapidly when wet and takes forever to dry. Before climbing into your down bag for the night, you should also lay the bag out, puff it up, and allow a few minutes for the down to do its work and trap the air. Lightweight, reassuringly expensive, compact and oh-so comfy! A down bag should be treated with respect and cared for, choose the best that you can afford and you will be blessed with many years of quality sleep.
- Synthetic: Modern Synthetic Bags are more durable in their capacity for all-round use and are excellent for base or family camping. Through modern technology, quality synthetic sleeping bags have had their bulk and weight greatly reduced to become a viable alternative to down when buying on a budget or when transportation is not such an issue. As with a down bag, a quality synthetic sleeping system will be constructed using a DWR coating and as previously mentioned helps to protect the bag, but will not keep it waterproof. The good news is though that a synthetic bag will keep much of its insulating qualities when wet and will dry quickly compared to a down bag. Needless to say, but if you are heading out to a typically wet area (UK summer!) then a synthetic bag might well be high on your list of priorities.
Outer shell construction of a quality sleeping bag is typically constructed from Ripstop Nylon/Polyester for durability and will have a Durable Water Repellent (DWR) coating to help protect the insulation from moisture ingress.
A DWR coating is not used in the lining of the bag, this is to enable body moisture to pass through the bag, moderating the body temperature.
Shapes And Features
The most common shapes for sleeping bags are mummy or rectangular and are constructed that way for different reasons.
Mummy: Following the natural shape of the body, a mummy shaped bag will be wider at the top to accommodate the shoulders, tapering sharply towards the feet and into a box shaped foot section. Contouring the body vastly reduces the amount of dead air trapped between you and is the most efficient way of keeping you warm.
Women are well catered for here, where many manufacturers produce a women's shaped bag: narrower at the shoulders and wider in the mid (hip) area and have extra insulation in the foot box and upper body sections
For some people, a mummy bag can feel a little claustrophobic so its worth trying one out first, but that said, if you are venturing out high into the wilds or cold climes, then a mummy bag should be seriously considered.
Some mummy shaped bags are designed be zipped together if required to form a blanket, but only when left and right bags are used and have compatible zips
Look out for internal storage compartments near the shoulder areas to stash and keep your socks or M&M's warm. With most bags you will also find a handy, small external pocket for your MP3 player etc...
Rectangular: These basic sleeping bags are cut wide at the shoulders and maintain the same width down to the feet, thus giving you plenty of room to thrash around in but tend to be much less effective at keeping you warm in cooler temperatures.
On the plus side, they do have the added ability to easily to zip together to form a large blanket if required and if the zippers are compatible.
Rectangular bags are ideal for low level family camping and when weight, bulk and transport is less of an issue.
Storage And Care
Always air and dry your sleeping bag at every opportunity, even when out on the hill before de-camping for the day – weather permitting of course, and remember to empty those dirty socks from the foot section too!
On returning home after an expedition or camping holiday it's always worth taking time out to hang the sleeping bags for a few days in a suitable dry place to get rid of any lingering smells, and to let the bag breathe.
If going into storage for any length of time, leave the bag out of its compression sack (some may come with a storage bag) so that the insulation fibres or down are not restricted or break down under prolonged compression.
Always read and follow the manufacturers recommendations for cleaning your sleeping bag for long-term durability and comfort.