Fence
A fence is a structure that encloses an area, typically outdoors creating a boundary, and is usually constructed from posts that are connected by boards, wire, rails or netting. A fence differs from a wall in not having a solid foundation along its whole length.
Alternatives to fencing include a ditch.
Types
By function
- Agricultural fencing, to keep livestock in and/or predators out
- Blast fence, a safety device that redirects the high energy exhaust from a jet engine
- Sound barrier or acoustic fencing, to reduce noise pollution
- Crowd control barrier
- Privacy fencing, to provide privacy and security
- Temporary fencing, to provide safety, security, and to direct movement; wherever temporary access control is required, especially on building and construction sites
- Perimeter fencing, to prevent trespassing or theft and/or to keep children and pets from wandering away.
- Decorative fencing, to enhance the appearance of a property, garden or other landscaping
- Boundary fencing, to demarcate a piece of real property
- Newt fencing, amphibian fencing, drift fencing or turtle fence, a low fence of plastic sheeting or similar materials to restrict movement of amphibians or reptiles.
- Pest-exclusion fence
- Pet fence, an underground fence for pet containment
- Pool fence
- Snow fence
- School fence
- Solar fence
Another aim of using a fence is to limit intrusion. In support of these barriers there are sophisticated technologies that can be applied on the fence itself to strengthen the defence of an area, such as:
- Detectors
- Peripheral alarm control unit
- Means of deterrence
- Means for communicating information remotely
- Remote alarm receiving unit
By construction
- Brushwood fencing, a fence made using wires on either side of brushwood, to compact the brushwood material together.
- Chain-link fencing, wire fencing made of wires woven together
- Chicane
- Close boarded fencing, strong and robust fence constructed from mortised posts, arris rails and vertical feather edge boards
- Composite Fencing, made from a mixture of recycled wood and plastic
- Expanding fence or trellis, a folding structure made from wood or metal on the scissor-like pantograph principle, sometimes only as a temporary barrier
- Ha-ha
- Hedge, including:
- * Cactus fence
- * Hedgerows of intertwined, living shrubs
- * Live fencing is the use of live woody species for fences
- * Turf mounds in semiarid grasslands such as the western United States or Russian steppes
- Hurdle fencing, made from moveable sections
- Pale fence, or "post-and-rail" fence, composed of pales - vertical posts embedded in the ground, with their exposed end typically tapered to shed water and prevent rot from moisture entering end-grain wood - joined by horizontal rails, characteristically in two or three courses.
- Palisade, or stakewall, made of vertical pales placed side by side with one end embedded in the ground and the other typically sharpened, to provide protection; characteristically two courses of waler are added on the interior side to reinforce the wall.
- Picket fences, generally a waist-high, painted, partially decorative fence
- Roundpole fences, similar to post-and-rail fencing but more closely spaced rails, typical of Scandinavia and other areas rich in raw timber.
- Slate fence, a type of palisade made of vertical slabs of slate wired together. Commonly used in parts of Wales.
- Split-rail fence, made of timber, often laid in a zig-zag pattern, particularly in newly settled parts of the United States and Canada
- Vaccary fence, for restraining cattle, made of thin slabs of stone placed upright, found in various places in the north of the UK where suitable stone is had.
- Vinyl fencing
- Solid fences, including:
- * Dry-stone wall or rock fence, often agricultural
- * Stockade fence, a solid fence composed of contiguous or very closely spaced round or half-round posts, or stakes, typically pointed at the top. A scaled down version of a palisade wall made of logs, most commonly used for privacy.
- Wattle fencing, of split branches woven between stakes.
- Wire fences
- * Smooth wire fence
- * Barbed wire fence
- * Electric fence
- * Woven wire fencing, many designs, from fine chicken wire to heavy mesh "sheep fence" or "ring fence"
- * Welded wire mesh fence
- Wood-panel fencing, whereby finished wood planks are arranged to make large solid panels, which are then suspended between posts, making an almost completely solid wall-like barrier. Usually as a decorative perimeter.
- Wrought iron fencing, also known as ornamental iron
Legal issues
Required use
The following types of areas or facilities often are required by law to be fenced in, for safety and security reasons:- Facilities with open high-voltage equipment. Transformer stations are usually surrounded with barbed-wire fences. Around mast radiators, wooden fences are used to avoid the problem of eddy currents.
- Railway lines
- Fixed machinery with dangerous mobile parts
- Explosive factories and quarry stores
- Most industrial plants
- Airfields and airports
- Military areas
- Prisons
- Construction sites
- Zoos and wildlife parks
- Pastures containing male breeding animals, notably bulls and stallions.
- Open-air areas that charge an entry fee
- Amusement equipment which may pose danger for passers-by
- Swimming pools and spas
History
File:Bolivar Heights Battlefield, fence on Bakerton Road.jpg|thumb|Buck-and-rail fencing such as this in West Virginia was ubiquitous in the Eastern Theater of the American Civil War, as it was easily made as long as there was plenty of timber readily available. Soldiers from both sides of the war made use of wood from these fences for their camp fires.
File:Zagroda z Rożnowic.JPG|thumb|A wattle fence at Sanok-Skansen outdoor museum in Poland
In the United States, the earliest settlers claimed land by simply fencing it in. Later, as the American government formed, unsettled land became technically owned by the government and programs to register land ownership developed, usually making raw land available for low prices or for free, if the owner improved the property, including the construction of fences. However, the remaining vast tracts of unsettled land were often used as a commons, or, in the American West, "open range" as degradation of habitat developed due to overgrazing and a tragedy of the commons situation arose, common areas began to either be allocated to individual landowners via mechanisms such as the Homestead Act and Desert Land Act and fenced in, or, if kept in public hands, leased to individual users for limited purposes, with fences built to separate tracts of public and private land.