Tent

For other uses, see Tent (disambiguation).
A modern two person, lightweight hiking dome tent; it is tied to rocks as there is nowhere to drive stakes on this rock shelf

A tent  pronunciation  is a shelter consisting of sheets of fabric or other material draped over, attached to a frame of poles or attached to a supporting rope. While smaller tents may be free-standing or attached to the ground, large tents are usually anchored using guy ropes tied to stakes or tent pegs. First used as portable homes by nomadic peoples, tents are now more often used for recreational camping and temporary shelters.

Tents range in size from "bivouac" structures, just big enough for one person to sleep in, up to huge circus tents capable of seating thousands of people. The bulk of this article is concerned with tents used for recreational camping which have sleeping space for one to ten people. Larger tents are discussed in a separate section below.

Tents for recreational camping fall into two categories. Tents intended to be carried by backpackers are the smallest and lightest type. Small tents may be sufficiently light that they can be carried for long distances on a touring bicycle, a boat, or when backpacking.

The second type are larger, heavier tents which are usually carried in a car or other vehicle. Depending on tent size and the experience of the person or people involved, such tents can usually be assembled (pitched) in between 5 and 25 minutes; disassembly (striking) takes a similar length of time. Some very specialised tents have spring-loaded poles and can be 'pitched' in seconds, but take somewhat longer to strike.

History

Roman Military tents

Tents were used at least as far back as the early Iron Age. They are mentioned in the Bible; for example, in the Genesis 4:20 Jabal is described as 'the first to live in tents and raise sheep and goats'. The Roman Army used leather tents, copies of which have been used successfully by modern reenactors.[1] Various styles developed over time, some derived from traditional nomadic tents, such as the yurt.

Most military tents throughout history were of a simple ridge design. The major technological advance was the use of linen or hemp canvas for the canopy versus leather for the Romans. The primary use of tents was still to provide portable shelter for a small number of men in the field.

By World War I larger designs were being deployed in rear areas to provide shelter for support activities and supplies.

Use

Tents are used as habitation by nomads, recreational campers, and disaster victims. Tents are typically used as overhead shelter for festivals, weddings, backyard parties, and major corporate events. They are also used for excavation (construction) covers, industrial shelters.

Traditional

Tents have traditionally been used by nomadic people all over the world, such as Native Americans, Mongolian, Turkic and Tibetan Nomads, and the Bedouin.

Military

U.S. Army tent with constructed wooden entrance, air conditioner, and sandbags for protection. Victory Base, Baghdad, Iraq (April 2004).

Armies all over the world have long used tents as part of their working life. Tents are preferred by the military for their relatively quick setup and take down times, compared to more traditional shelters. One of the world's largest users of tents is the US Department of Defense. The US Department of Defense has strict rules on tent quality and tent specifications. The most common tent uses for the military are temporary barracks (sleeping quarters), DFAC buildings (dining facilities), field headquarters, Morale, Welfare, and Recreation (MWR) facilities, and security checkpoints. One of the most popular military designs currently fielded by the US DoD is the TEMPER Tent. TEMPER is an acronym for Tent Expandable Modular PERsonnel. The U.S. military is beginning to use a more modern tent called the deployable rapid assembly shelter or DRASH. It is a collapsible tent with provisions for air conditioning and heating.[2]

Recreational

Camping is a popular form of recreation which often involves the use of tents. A tent is economical and practical because of its portability and low environmental impact. These qualities are necessary when used in the wilderness or backcountry.

Emergency

Tents are often used in humanitarian emergencies, such as war, earthquakes and fire. The primary choice of tents in humanitarian emergencies are canvas tents, because a cotton canvas tent allows functional breathability while serving the purpose of temporary shelter. Tents distributed by organisations such as UNHCR are made by various manufacturers, depending on the region where the tents are deployed, as well as depending on the purpose.

At times, however, these temporary shelters become a permanent or semi-permanent home, especially for displaced people living in refugee camps or shanty towns who can't return to their former home and for whom no replacement homes are made available.

Protest movements

Tents are also often used as sites and symbols of protest over time.[3] In 1968 Resurrection City saw hundreds of tents set up by anti-poverty campaigners in Washington D.C. In the 1970s and 1980s anti-nuclear peace camps spread across Europe and North America, with the largest women's-only camp to date set up at the Greenham Common US RAF base in Newbury, England to protest cruise missiles during the Cold War. The 1990s saw environmental protest camps as part of the campaign for the Clayoquot Sound in Canada and the roads protests in the UK. The first No Border Network camp was held in Strasbourg in 2002, becoming the first in a series of international camps that continue to be organised today. Other international camps of the 2000s include summit counter-mobilisations like Horizone at the Gleneagles G8 gathering in 2005 and the start of Camp for Climate Action in 2006.[4] Since September 2011, the tent has been used as a symbol of the Occupy movement, an international protest movement which is primarily directed against economic and social inequality. Occupy protesters use tents to create camps in public places wherein they can form communities of open discussion and democratic action.

General considerations

A simple tented shelter

Tent fabric may be made of many materials including cotton (canvas), nylon, felt and polyester. Cotton absorbs water, so it can become very heavy when wet, but the associated swelling tends to block any minute holes so that wet cotton is more waterproof than dry cotton. Cotton tents were often treated with paraffin to enhance water resistance. Nylon and polyester are much lighter than cotton and do not absorb much water; with suitable coatings they can be very waterproof, but they tend to deteriorate over time due to a slow chemical breakdown caused by ultraviolet light. The most common treatments to make fabric waterproof are silicone impregnation or polyurethane coating. Since stitching makes tiny holes in a fabric seams are often sealed or taped to block these holes and maintain waterproofness, though in practice a carefully sewn seam can be waterproof.

Rain resistance is measured and expressed as hydrostatic head in millimetres (mm). This indicates the pressure of water needed to penetrate a fabric. Heavy or wind-driven rain has a higher pressure than light rain. Standing on a groundsheet increases the pressure on any water underneath. Fabric with a hydrostatic head rating of 1000 mm or less is best regarded as shower resistant, with 1500 mm being usually suitable for summer camping. Tents for year-round use generally have at least 2000 mm; expedition tents intended for extreme conditions are often rated at 3000 mm. Where quoted, groundsheets may be rated for 5000 mm or more.

Many tent manufacturers indicate capacity by such phrases as "3 berth" or "2 person". These numbers indicate how many people the manufacturer thinks can use the tent, though these numbers do not always allow for any personal belongings, such as luggage, inflatable mattresses, camp beds, cots, etc., nor do they always allow for people who are of above average height. Checking the quoted sizes of sleeping areas reveals that several manufacturers consider that a width of 150 cm (4.9 ft) is enough for three people — snug is the operative word. Experience indicates that camping may be more comfortable if the actual number of occupants is one or even two less than the manufacturer's suggestion, though different manufacturers have different standards for space requirement and there is no accepted standard.

If the tent will be used where mosquitoes, gnats and other biting insects are expected, it should have all window, vent and door openings covered with fine-mesh "no-see-um" netting.

Tents can be improvised using waterproof fabric, string, and sticks.

List of traditional types

Detail of an early 18th-century tent in the District Museum in Tarnów, richly decorated in Muslim motifs and equipped with windows – an example of luxury tent-making for the Polish–Lithuanian Commonwealth's magnateria.

Parts

A variety of dome tents. Small dome and tunnel tents are the most popular tents amongst travellers due to their light weight and quick/easy placement
Junjik Valley man and wall tent. Picture from the U.S. Fish and Wildlife Service, July 1973

There are three basic configurations of tents, each of which may appear with many variations:

Single skin (USA: single wall): Only one waterproof layer of fabric is used, comprising at least roof and walls. To minimize condensation on the inside of the tent, some expedition tents use waterproof/breathable fabrics.

Single skin with flysheet: A waterproof flysheet or rain fly is suspended over and clear of the roof of the tent; it often overlaps the tent roof slightly, but does not extend down the sides or ends of the tent.

Double skin (USA: double wall): The outer tent is a waterproof layer which extends down to the ground all round. One or more 'inner tents' provide sleeping areas. The outer tent may be just a little larger than the inner tent, or it may be a lot larger and provide a covered living area separate from the sleeping area(s). An inner tent is not waterproof, but allows water vapour to pass through so that condensation occurs only on the exterior side. The double layer may also provide some thermal insulation. Either the outer skin or the inner skin may be the structural component, carrying the poles; the structural skin is always pitched first, though some tents are built with the outer and inner linked so that they are both pitched at the same time.

Components:

A wooden stake supporting a tent.

Design factors

A large family tent for car-camping, with a portable gazebo.
A small, two-person, backpacking tent

Many factors affect tent design, including:

Shelters

A gazebo provides a useful shelter
A dining fly

Shelters are not normally used for sleeping. Instead they may act as a store or provide shelter from sun, rain, or dew.

Modern styles

Typical lightweight and trekking tent designs: 1. geodesic tent, 2. dome tent, 3. tunnel tent, 4. ridge tent, 5. pyramid tent

With modern materials, tent manufacturers have great freedom to vary types and styles and shapes of tents.

Rigid poles

Many tents which use rigid steel poles are free-standing and do not require guy ropes, though they may require pegs around the bottom edge of the fabric. These tents are usually so heavy (25 to 80 kg) that it takes a rather strong wind to blow them away.

Flexible poles

Flexible poles used for tents in this section are typically between 3 and 6 metres long (10 and 20 feet). Cheap poles are made of tubes of fibreglass with an external diameter less than 1 cm (1/3 inch), whereas more expensive aluminium alloys are the material of choice for added strength and durability. For ease of transportation, these poles are made in sections some 30 cm to 60 cm long (1 to 2 ft), with one end of each section having a socket into which the next section can fit. For ease of assembly, the sections for each pole are often connected by an internal elastic cord running the entire length of the pole.

This is a basic dome tent, shown without rain fly or stakes.
The basic dome has a rectangular floor and two poles which cross at the peak; each pole runs in a smooth curve from one bottom corner, up to the peak, and then down to the diagonally opposite bottom corner. There are usually special fittings at each corner which fit into sockets at the ends of each pole – pole tension keeps everything in shape. The poles can run on either the inside or outside of the tent fabric. When located on the interior, poles are held in place by a variety of means including hook and loop style straps, clips, and other fastening hardware. Poles that are located on the outside of the tent fabric are attached via fabric pole sleeves or plastic clips. Dome tents do not require guy ropes and pegs for structural integrity as they are considered free-standing, but must be pegged down in high winds.
The basic dome design has been modified extensively, producing tents with three poles, tents with irregularly-shaped bases, and other unusual types. A common variation is to add a third pole between two adjacent corners; this is angled away from the tent and supports an extension of the flysheet, to give a porch/storage area.
Tunnel tent
Tent used by mountaineers in Nepal
A basic tunnel tent uses two or more flexible poles, arranged as parallel hoops, with tent fabric attached to form a half-cylinder or tapering tunnel. The most common designs have a sleeping area at one end and a vestibule area at the other, though vestibules (possibly extended) at each end are not uncommon, or vis-a-vis sleeping at either end and a central opening to a common vestibule area are made too.

Inflatable airbeams

Inflatable pole supports, also known as airbeams, serve as rigid structural supports when inflated but are soft and pliable when deflated. Tents using such technology are neither commonly used nor widely accepted and are available from a very limited number of suppliers.

Much like a bicycle tube and tire, airbeams are often composed of a highly dimensionally stable (i.e. no stretch) fabric sleeve and an air-holding inner bladder. However, other airbeam constructions consist of coated fabrics that are cut and manufactured to its intended shape by a method such as thermal welding. Depending on the desired tent size, airbeams can be anywhere from 2-40 inches in diameter, inflated to different pressures.[5] High pressure airbeams (40-80 psi) that are filled by compressors are most often used in larger shelters, whereas low pressure beams (5-7 psi) are preferred for recreational use.[6] The relatively low pressure enables the use of a manual pump to inflate the airbeam to the desired level. Airbeams have the unique quality of bending, rather than breaking, when overloaded. Tents that use inflatable airbeams are structured almost identically to those that use flexible poles.

Inflatable airbeam tunnel tent

Older tent styles

A tent from Boulanger's painting C'est Un Emir.
U.S. Army pup tent in World War II

Most of these tent styles are no longer generally available. Most of these are single-skin designs, with optional fly sheets for the ridge tents.

All the tents listed here had a canvas fabric and most used a substantial number of guy ropes (8 to 18). The guys had to be positioned and tensioned fairly precisely in order to pitch the tent correctly, so some training and experience were needed. Pup tents might use wooden or metal poles, but all the other styles mentioned here used wooden poles.

Marquees and larger tents

The Big Top of Billy Smart's Circus Cambridge 2004
WOMEX 15 tent - Budapest
Wedding tent in Armenia

These larger tents are seldom used for sleeping.

A typical 20'x20' high peak frame tent.

Influence on building design

Tent design has influenced many large modern buildings. These buildings have in turn influenced the next generation of tent design. Tent-style tensile structures are used to cover large public areas such as entertainment venues, arenas and retail areas (example: The O2) or sports stadiums (example: Munich Olympic Stadium) and airports (example: Denver International Airport).

See also

References

  1. "ContuberniumTent". Legiotricesima.org. Retrieved 2012-11-23.
  2. "The United States Army | About the NSSC". Natick.army.mil. 2009-10-20. Retrieved 2012-11-23.
  3. "The Book". Protest Camps. Retrieved 2012-11-23.
  4. "experiments in alternative worlds". Protest Camps. Retrieved 2012-11-23.
  5. "SSC Developing Multiple Uses for Air Beam Shelter". Defense Industry Daily. 2005-05-10. Retrieved 2007-12-25.
  6. "Shelter from the CB storm". Military Medical Technology. 2004-04-08. Archived from the original on 2007-10-11. Retrieved 2007-12-25.
  7. "Air Support: Inflatable Structures Pump Up the Military". Military.com. 2005-01-01. Retrieved 2007-12-25.
  8. "Shelter Half Pup Tent". olive-drab.com.

External links

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