Expanded metal versus Palisade fencing
Paul Green, security specialist at The Expanded Metal Company, examines the differences between palisade fencing and expanded metal mesh fencing.
Look at any site with perimeter protection or pay attention to the fencing that is preventing access to train tracks, and you’ll often see either expanded metal mesh or palisade fencing being employed. Both types of security fencing have their advantages – but why should you choose one over the other?
The use of palisades – originally wooden stakes driven into the ground side by side to form a barrier – can be traced back to ancient Greece and Rome, where they were used to protect military camps. Wooden palisades were also used by Native American societies.
Metal palisade fencing is today used across multiple sectors as a low-cost perimeter security solution. It is very easy to transport over rough terrain and is simple to install over sloping terrain, so as well as urban applications, palisade fencing is often employed in rural or more remote areas.
However, there are several disadvantages to palisade from a security perspective.
• Palisade pales can easily be removed through attacking its two fixing points with common items such as a screwdriver or chisel.
• Palisade pales can also be levered by using common car jacks.
• Damaged palisade pales can be left in situ by would be criminals who can continue to use it as a point of easy access without it ever being noticed and remedial action being undertaken.
• Palisade fencing can require intensive and costly maintenance due to ease of attack.
• By design, the pales can inhibit visibility of CCTV and other surveillance measures.
• The gaps in palisade fencing are still large enough to allow the ingress of wild animals or for narrow objects to be passed through.
• Palisade fencing can be easily scaled with the addition of duct tape to create a temporary ladder.
• Removing just one pale in a palisade fence can allow a body to pass through
• Palisade often needs to be reinforced with other materials such as expanded metal in order to enhance security performance, which can cancel out the original cost savings.
• The shape of each pale throws up issues of liability through impalement and misadventure.
Expanded metal mesh is a comparatively more recent security solution. Originally developed in the 1880s by John French Golding, the inventor and patentee of expanded metal and founder of The Expanded Metal Company, expanded metal mesh was originally widely used in the construction industry.
However, its qualities give the material several advantages as a fencing solution – and for many years it has been widely used as a fencing solution across the world. Certified, high-end double skinned security fencing such as ExMesh™ SR3 is used to protect critical infrastructure, government and military sites and high-risk areas, while lower cost options such as ExMesh™ Fastrack have been designed to be used across miles of railway embankments to protect transport infrastructure and the public.
Expanded metal mesh boasts several qualities which make it highly suitable as a security fencing solution.
• Expanded metal mesh is formed from one piece of material, meaning there is nothing to work loose, no fretting strands or strained joins or welds. This means that it is tougher to break through than alternative types of fencing.
• Expanded metal mesh panels cannot be easily targeted at its welds or simply parted with common tools such as scissor jacks.
• The uncut knuckles of expanded metal mesh withstand force better than welds or joints.
• The apertures of expanded metal mesh fencing are small compared to the gaps between palisade pales, meaning it is more difficult (or impossible) to pass anything through the fencing.
• The design and shape of expanded metal mesh allows for greater visibility through the material than that offered by palisade. This has advantages when CCTV is used in conjunction with perimeter fencing.
• Cutting through expanded metal can generate sharp edges around any breach in the material – making it more difficult to pass through.
• Available in different patterns and finishes, expanded metal can offer a more aesthetically pleasing solution to palisade.
Check out the video below which shows just how difficult expanded metal mesh fencing is to break through…