Sleeping Bag Information and Advice
Sleeping Bags - Season Ratings Explained
Sleeping Bags are typically categorised into Season Ratings, but these ratings should only be considered as a guide and not a guarantee of the bags suitability for your needs.
The following table shows what is generally meant for each season rating.
Although sleeping bags are grouped into season ratings you should bear in mind the following:-
Sleeping Bags - Temperature Ratings ExplainedYou will typically see two temperature ratings quoted: the Comfort Temperature Rating and the Extreme Temperature Rating. What are they? What do they mean?
The Comfort Temperature Rating - is shown as a range e.g. +12°C to +25°C. The range is generally understood to refer to the ambient temperature around you. The first temperature quoted in this range is the lowest the manufacturer considers you will remain comfortable in. Naturally, the second value is the highest temperature that they consider you will remain comfortable in.
From the beginning of 2005, sleeping bags that meet the standard should display 4 temperature ratings:
Sleeping Bags - Insulation Choices ExplainedDown - is warm, lightweight and packable. If well cared for, it retains its loft up to three times longer than most synthetics. However, when it is wet, the thermal properties of down are virtually eliminated. Down forms clumps if exposed to dampness or moisture and therefore it performs best in cold dry climates.
Synthetic Meterials - the majority of sleeping bags use synthetic materials for insulation (the fill). The most common synthetic threads are usually hollow, reducing their weight and enabling them to trap more air.
The positives for synthetic fill are
Construction MethodThe method used to keep the fill in place. It is no good having an efficient insulation material if it all ends up at one end of the sleeping bag.
The Single Layer Construction:
Sleeping Bag Features
Zips - as well as enabling easy access, zips can be used to control temperature in the sleeping bag - particularly those fitted with, '2-way' zips. On warm nights you can ventilate the bag from the bottom, this is very handy for bags with a high temperature rating. Another aspect of zips to bear in mind is the baffle. Zips create a cold spot, so the baffle insulates it thus avoiding that
cold shock sensation.
Hoods - Ever found you are all snug inside your sleeping bag but the top of your head does not feel quite as confortable - a sleeping bag fitted with a hood will come to your rescue. Many can be adjust
ed with the use of a simple drawcord.
Neck Baffles - the purpose of the neck baffle is to prevent the air your body has already made warm escaping. If this happens cold air drafts in particularly down the back of the neck. Typically they are adjusted by the use of a drawcord.
The Sleeping Bag Shape - essentially bags can be grouped into two shapes - the mummy shaped bags or rectangular bags
Stuff Sacs - these enable easy transport and most incorporate compression straps to reduce the pack size. However, many people make the mistake of storing their sleeping bag in the stuff sac. This is bad for the filling and reduces the efficiency. For long term storage, the bag should be loose, not tightly packed.
Useful Sleeping Bag AccessoriesSleeping Bag Liners
A versatile way of adding extra wamth, making it possible to use your sleeping bag in colder conditions. Most liners are easier to clean than sleeping bags and are made using soft materials that enhance your comfort.
In warm weather, a liner alone can make a comfortable alternative to a sleeping bag.
When laying in your sleeping bag the bottom insulation or 'fill' is compressed making it less thermally efficient. Additionally, the ground temperature is always colder than your body temperature. Mattresses combat these two problems adding extra insulation just where it is needed. They also help to keep the underside of the sleeping bag cleaner.