Sleeping bag

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A mummy bag, so named because it has an insulated hood which keeps the head warm. A foam sleeping pad can be seen underneath the sleeping bag. Mummy bag.jpg
A mummy bag, so named because it has an insulated hood which keeps the head warm. A foam sleeping pad can be seen underneath the sleeping bag.

A sleeping bag [1] is an insulated covering for a person, essentially a lightweight quilt that can be closed with a zipper or similar means to form a tube, which functions as lightweight, portable bedding in situations where a person is sleeping outdoors (e.g. when camping, hiking, hill walking or climbing). It is also commonly used indoors for people who do not have beds or at sleepovers. Its primary purpose is to provide warmth and thermal insulation through its synthetic or down insulation. It also typically has a water-resistant or water-repellent cover that protects, to some extent, against wind chill and light precipitation, but a tent is usually used in addition to a sleeping bag, as it performs those functions better. The bottom surface also provides some cushioning, but a sleeping pad or camp cot is usually used in addition to that purpose. The bottom surface of a sleeping bag may be moderately water repellent, but a plastic tarp or groundsheet is often used to protect against moist ground.


There are a range of sleeping bag models designed for different purposes. Very lightly insulated sleeping bags are designed for summer camping use or indoor use by children during slumber parties. Well-insulated bags are designed for cold weather use. The most well-insulated and lightweight sleeping bags, which are designed for serious hikers and adventurers, are more expensive than lightly insulated sleeping bags. One subcategory of cold-weather sleeping bags, the mummy bag, is so named because it has an insulated hood for the head. A bivouac sack (bivy) is a waterproof cover for a sleeping bag that may be used in place of a tent by minimalist, experienced hikers. A bivy bag may also be carried by day hikers as a backup or emergency shelter, to be used if they cannot make it back to their starting point by nightfall due to inclement weather or getting lost.


A three-person buffalo sleeping bag used during Arctic exploration circa 1880 Three person buffalo sleeping bag.jpg
A three-person buffalo sleeping bag used during Arctic exploration circa 1880

The "Euklisia Rug", from Ancient Greek εὖ (well) and κλισία (cot, sleeping-place), patented by mail-order pioneer Pryce Pryce-Jones in 1876, [2] may have been the first forerunner of the modern sleeping bag. Pryce-Jones, a Newtown, Montgomeryshire Welsh entrepreneur developed the bag and exported it around the world in the late 19th century. Documents show he sold 60,000 of these rugs to the Russian army – and the British Army also bought them. There are records of civilian uses among missionaries in Africa and pioneers in the Australian outback. [3]

Design types

Russian sleeping bag used in space station Mir and International Space Station Sleeping bag for space.JPG
Russian sleeping bag used in space station Mir and International Space Station

A basic sleeping bag is simply a square blanket or quilt, fitted with a zipper on two or three sides, which enables users to get into the bag and then close it up. A sleeping bag of this type is packed by being folded in half or thirds, rolled up, and bound with straps or cords with cord locks. The basic design works well for most camping needs but is inadequate under more demanding circumstances.

The second major type of sleeping bag, sometimes called a mummy bag because of its shape, is different in several important ways. It tapers from the head end to the foot end, reducing its volume and surface area, and improving its overall heat retention properties. Some bags are designed especially to accommodate women's body shapes. Most mummy bags do not unzip to the feet, because the zipper is a weak point in any sleeping bag's insulating qualities. Together with the tapered shape, this design feature helps protect the feet, which are more vulnerable to heat loss than other parts of the body. [ citation needed ] Another design feature is a drawstring, equipped with a cord lock, at the head end to help prevent the escape of warm air. A mummy bag often cannot be rolled neatly like a rectangular bag. Instead, it is simply stuffed into a stuff sack or compression sack.

The bottom of a sleeping bag typically does not provide significant insulation, because body weight crushes the loft of the insulation material. It is therefore necessary to use a pad or other less crushable insulation underneath the sleeper, especially in cold weather. Due to this, some sleeping bags do not include insulation on the bottom. Some include a sleeve for holding a sleeping pad. Additionally, some campers, especially ultralight backpackers or hammock campers, have started to use a top quilt, essentially a sleeping bag without a back. Some top quilts include a foot box, while others are just simple blankets.


A highly compact sleeping bag measuring 23 cm (9 in) with a diameter of 12 cm (5 in) when packed but 210 cm x 65 cm (6.89 ft x 2.13 ft) when unfolded. Compactsleepingbag.jpg
A highly compact sleeping bag measuring 23 cm (9 in) with a diameter of 12  cm (5 in) when packed but 210 cm × 65 cm (6.89 ft × 2.13 ft) when unfolded.

Many insulating materials are available for sleeping bags. Inexpensive sleeping bags for warm weather use or use by children indoors typically have a layer of synthetic quilt insulation. Outdoor professionals and serious amateur adventurers usually prefer either synthetic fill (e.g. PrimaLoft), or natural fill (e.g. down), and they have debated the merits of these materials for years.

Synthetic fill does not readily absorb water, dries easily, and provides some warmth even when thoroughly soaked. These properties may save the user's life if, for example, the sleeping bag is accidentally dropped into water on a cold day. Synthetic material is also firm and resilient, so it insulates well even underneath a person's weight. However, synthetic fill cannot be compressed as much and is heavier, so the load volume and weight are greater with synthetic fill bags. Furthermore, synthetic insulation tends to break down faster than its natural counterpart.

Downfill weighs less than synthetic and retains heat better, but usually costs more. Down must be kept dry; a soaked down sleeping bag may provide even less insulation than no sleeping bag at all, leading to hypothermia. Newer, more technically advanced sleeping bags often have water-resistant shells and can be used in damper conditions. It is also recommended to keep a sleeping bag in a larger sack (storage sack) as opposed to a small traveling sack (compression bag) during long periods of storage. However, many regular backpackers and hikers agree that hanging a sleeping bag, and taking care to move the position of the bag on the hanger at intervals to not create a "dead spot" (a spot where the fill has been crushed so that it is no longer useful), is the best method of storing a bag for long periods.

Other materials, notably cotton and wool, have also been used for sleeping bags. Wool repels water nicely and also resists compression, but it weighs much more than any alternative. Cotton suffers from high water retention and significant weight, but its low cost makes it an attractive option for uses like stationary camping or car camping where these drawbacks are of less consequence. Cotton insulation does not provide warmth if it becomes wet (due, for example, to the sleeping bag falling into water), so cotton-insulated sleeping bags are not used by professionals or serious hikers.

Temperature ratings

A person in a sleeping bag Israel 2 021 Sleeping Rucksack-Tourist.jpg
A person in a sleeping bag

In Europe, the EN 13537 standard (introduced in 2005) normalizes the temperatures at which a sleeping bag is rated for use. In March 2010, REI began requiring American manufacturers to follow the EN 13537 standard, [4] and in October 2016, ISO 23537-1:2016 standard replaced the EN 13537 standard. [5]

TheA test, relying on a heated mannequin, provides four temperatures:

The transition zone, in between the comfort and lower temperature, is usually considered as the best purchase guideline.

A sleeping bag's rating typically indicates the lowest temperature at which it will keep the average sleeper warm. For example, with a 0 °C bag, a person should be able to sleep in 0 °C temperature, but not necessarily comfortably.

Girls with sleeping bags at a sleepover. Detske6.jpg
Girls with sleeping bags at a sleepover.

There is no standard measurement rating in the U.S., so a 20 °F (−7 °C) bag from one company may not provide the same warmth as a 20 °F (−7 °C) from another company. Other important variables include what the user plans to wear while sleeping, what type of sleeping pad is used, and how well the user holds heat in the bag.

It has been shown that moisture (either externally, or from sweating) severely decreases the insulating effect of sleeping bags. [6]

Indoor sleeping bags

Indoor sleeping bags, sometimes called slumber bags, are widely available, often for use, particularly by children. These are usually not designed to be weatherproof and are often made of natural fabrics instead of synthetic fabrics commonly used for outdoor sleeping bags. Children's sleeping bags in particular often feature elaborate, brightly colored printed designs, such as images of popular media characters. Slumber bags make floor sleeping more comfortable, and are often used for sleepovers, family visits, and other situations where there are not enough beds for everyone or someone does not feel comfortable sharing a bed.

A child in an infant sleeping bag. Alvi Babyschlafsack.jpg
A child in an infant sleeping bag.

The Icehotel in Jukkasjärvi, Sweden provides polar-tested sleeping bags for use while sleeping on their beds, which are bedded with reindeer furs and have frames carved from ice.

Infant use

An infant sleeping bag is a bag-like garment or covering worn by infants for sleeping in. Infant sleeping bags differ from regular sleeping bags in design and purpose, being designed primarily for indoor rather than outdoor use, and usually featuring either arm holes or sleeves.

In the market, there are available for winter and summer baby sleeping bags. Also, some brands make all-season baby sleeping bags.

A toddler in a merino wool sleeping bag Woolrex Merino Wool Baby Sleeping Bag.jpg
A toddler in a merino wool sleeping bag

The definition used in the British Standard [7] For the safety of children sleep bags are "sleep bags for the use of children with a minimum weight of 4  kg designed to provide sufficient warmth to remove the need for additional bedding when sleeping in a cot or similar product in which a child is contained." It goes on to exclude "garments with sleeves and feet, i.e. sleep suits or baby grows, or to products designed primarily for outdoor use or to keep children warm when in a pushchair."

See also

Related Research Articles

<span class="mw-page-title-main">Backpack</span> Bag carried on ones back

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<span class="mw-page-title-main">Sleeping pad</span>

In camping, a ground pad, sleeping pad, thermal pad, sleeping mat, or roll mat is lightweight pad, common among hikers, backpackers and budget travelers, often used in conjunction with a sleeping bag. Its purpose is to provide padding and thermal insulation. All types currently available use air as their primary form of insulation.

<span class="mw-page-title-main">Duvet</span> Type of bedding

A duvet, usually called a comforter or (down-filled) quilt in American English, and a doona in Australian English, is a type of bedding consisting of a soft flat bag filled with either down, feathers, wool, cotton, silk, or a synthetic alternative, and is typically protected with a removable cover, analogous to a pillow and pillow case. The term duvet is mainly British, especially in reference to the bedding; when rarely used in US English, it often refers to the cover. Sleepers often use a duvet without a top bed sheet, as the duvet cover can readily be removed and laundered as often as the bottom sheet. Duvets originated in rural Europe and were filled with the down feathers of ducks or geese. The best quality feathers are taken from the eider duck, which is known for its effectiveness as a thermal insulator. Prior to the uptake of the duvet as a popular bedding option in Britain from the 1970s onwards, the British "eiderdown", while also a feather-filled object, was essentially thinner than its "continental" equivalent and was used on top of a regular sheet and blankets for extra warmth when needed, and thus did not simplify the process of making the bed.

Earthbag construction is an inexpensive building method using mostly local soil to create structures which are both strong and can be quickly built.

<span class="mw-page-title-main">Backpacking (hiking)</span> Outdoor recreation of carrying gear on ones back, while hiking for more than a day

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<span class="mw-page-title-main">Bedding</span> Bed covering fabrics

Bedding, also called bedclothes or bed linen, is the materials laid above the mattress of a bed for hygiene, warmth, protection of the mattress, and decorative effect. Bedding is the removable and washable portion of a human sleeping environment. Multiple sets of bedding for each bed are often washed in rotation and/or changed seasonally to improve sleep comfort at varying room temperatures. Most standardized measurements for bedding are rectangular, but there are also some square-shaped sizes, which allows the user to put on bedding without having to consider its lengthwise orientation.

<span class="mw-page-title-main">Comforter</span> Type of bedcover

A comforter, also known as a doona in Australian English, or a continental quilt or duvet in British English, is a type of bedding made of two lengths of fabric or covering sewn together and filled with insulative materials for warmth, traditionally down or feathers, wool or cotton batting, silk, or polyester and other down alternative fibers. Like quilts, comforters are generally laid over a top bed sheet and used to cover the body during sleep. Duvets are another form of quilt, traditionally filled with feathers, though since the late 20th century often made of synthetic fibres or down alternatives.

<span class="mw-page-title-main">Thinsulate</span> Brand of thermal insulation used in clothing

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<span class="mw-page-title-main">Bivouac shelter</span> Improvised shelter

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<span class="mw-page-title-main">Space blanket</span> Aluminized plastic sheet used to protect against heat in space

A space blanket is an especially low-weight, low-bulk blanket made of heat-reflective, thin, plastic sheeting. They are used on the exterior surfaces of spacecraft for thermal control, as well as by people. Their design reduces the heat loss in a person's body, which would otherwise occur due to thermal radiation, water evaporation, or convection. Their low weight and compact size before unfurling make them ideal when space or weight are at a premium. They may be included in first aid kits and with camping equipment. Lost campers and hikers have an additional possible benefit: the shiny surface flashes in the sun, allowing its use as an improvised distress beacon for searchers and as a method of signalling over long distances to other people.

EN 13537 is a European standard designed to standardize the temperature ratings on sleeping bags manufactured and/or sold in Europe. As of 1 January 2005 a CEN criterion came into effect covering the testing and publication of temperature ratings for sleeping bags. The new criterion differs from the standards that existed formerly. In 2016 this standard was superseded by ISO EN 23537:2016.

Mountaineering, expedition or high altitude boots are a type of footwear used in mountain climbing. They are designed specifically for moving over harsh terrain.

<span class="mw-page-title-main">Ultralight backpacking</span> Style of hiking

Ultralight backpacking is a style of lightweight backpacking that emphasizes carrying the lightest and least amount of gear. While no technical standards exist, some hikers consider "ultralight" to mean an initial base weight of less than 4.5 kg (9.9 lb). Base weight is the weight of a fully loaded backpack at the start of a trip, excluding worn weight and consumables such as food, water, and fuel. Base weight can be lowered by reducing the weight of individual items of gear, or by choosing not to carry that gear. Ultralight backpacking is most popular among thru-hikers.

<span class="mw-page-title-main">Hammock camping</span>

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<span class="mw-page-title-main">PrimaLoft</span>

PrimaLoft® is a brand of patented synthetic microfiber thermal insulation material that was developed for the United States Army in the 1980s. PrimaLoft is a registered trademark of PrimaLoft, Inc., the brand's parent company.

<span class="mw-page-title-main">Down jacket</span> Quilted, padded jacket

The down jacket, known more commonly in the fashion industry as a puffer jacket or simply puffer, is a quilted coat which is insulated with either duck or goose feathers. Air pockets created by the bulk of the feathers allow for the retention of warm air.

<span class="mw-page-title-main">Sleeping bag liner</span>

Sleeping bag liners are lightweight cloth sacks usually fitted inside sleeping bags to provide extra comfort, insulation, and help keep the sleeping bag clean.


  1. Zeeshan, Haider. "Best Sleeping Bag For Camping and Outdoor". TheCampingTools. Zeeshan Haider. Retrieved 29 December 2023.
  2. "Euklisia Rug". Retrieved 24 August 2013.
  3. "A History of the World – Object : Euklisia Rug". BBC. 1 January 1970. Retrieved 24 August 2013.
  4. Pidgeon, Dave. "The Ratings Game: Standardizing Sleeping Bag Temperature Ratings". Backpacker. Cruz Bay Publishing. Retrieved 15 April 2019.
  5. "ISO 23537-1:2016 Requirements for sleeping bags". International Organization for Standards. Retrieved 15 April 2019.
  6. Camenzind, M., M. Weder, and E. Den Hartog. Influence of Body Moisture on the thermal insulation of sleeping bags, Symposium on "Blowing Hot and Cold: Protecting Against Climatic Extremes". Dresden, NATO RTO-MP-076 2001; KN4-1-KN4-15
  7. British Standard BS 8510:2009 Child use and care articles. Safety of children's sleep bags. Safety requirements and test methods.