Security for civil engineering and construction sites

Building and construction sites are often natural targets for thieves as they generally contain a lot of high value plant, materials and equipment. This can be easily accessible for criminals if proper and effective security measures are not put in place.

Providing security for construction sites can be particularly challenging because they are constantly changing. The site changes physically as it is being developed and built, and it changes in value as it grows and develops and different materials and equipment are brought on to the site. People that need to enter and exit the site also change on a regular basis as a construction project proceeds.

This article looks at some of the common risks faced by civil engineering and construction sites, and explores some of the methods and steps that can be taken to make them more secure.

Threats to construction sites

Each construction site will have its own particular security issues depending on the nature, size and location of the project, as well as the amount of time the project takes, but broadly speaking there are three types of threats to construction sites:

  • Threats to property and assets
  • Threats to operations
  • Threats to life

Theft, vandalism and terrorism are the main causes of these risks.


This includes theft of plant, fuel, and materials from the site. It can even include theft of personal possessions from construction workers. Theft from construction sites is extremely common for a couple of key reasons. Firstly because sites are constantly changing and people are constantly moving in and out from them makes them relatively easy targets for opportunistic thieves, and secondly because if the thief is successful then the high value of plant, materials and equipment on the site can provide them with a quick and easy profit. Theft of fuel from sites is particularly popular with thieves. Used in vehicles and generators across the site, it is of high value and is extremely useful to practically everyone, but is also very hard to trace. The theft of fuel can be very costly to construction sites, as machinery can’t work without it, and fuel tanks will most likely be damaged when it is stolen, both of which will delay the project and prove costly. Construction sites can fall foul to carefully planned thefts, but also opportunistic thefts, where someone realises that they can easily steal from the unprotected site and do so.

Vandalism and arson

Vandalism, deliberate damage or arson of construction sites is also common, and generally is carried out by people who just want to cause damage and destruction and see a local building site as the ideal place to release that pent up need. However, it may also be carried out by people with a particular axe to grind – such as people who are opposed to the construction project for political or commercial reasons, or people who don’t want the building to go ahead because of the effect that it will have on them or their property.


Whilst not as common as theft or vandalism, terrorism can still be a risk for some construction sites, especially if the site is particularly high profile, being built by or for a large, multinational company, has political connections, is located near to a potential target of terrorism, or is being built at a particular time. Terrorists can use attacks to get their message across, to delay or stop construction going ahead, or even more terrifyingly can position explosive materials with the building whilst it is still under construction, only to then detonate it once the building is complete and being used.

Other common issues

As well as these three major threats, there are a range of other potential threats to construction sites. These include:

  • intruders intent on committing suicide gaining access to the site
  • protesters gaining access to the site to either campaign against the construction project or just because they know it will give their cause publicity
  • attacks on construction workers by people opposed to the building work
  • using the construction site to access other buildings

These are all “manmade” risks, but you should also take into account the risk of natural hazards such as floods, storm damage, earthquakes or landslides. Other issues could also affect the security of the project and therefore should be considered, including if the suppliers business fails or runs out of money, or if staff are injured.

Risk Analysis

In order for everyone involved to be aware of the potential risks on a construction site and therefore to be able to determine the level of protection and security needed, it is recommended that a register is created. This should contain a list of all of the potential threats and hazards which could impact the construction site, and details of actions taken to combat these risks.

The register should include two distinct parts – a raw risk register and a residual risk register. The raw risk register outlines the risks, the chance of them happening and what impact they would have before any action has been taken. Measures are then put in place to mitigate the risk. The residual risk register then looks at those measures taken to see if they have reduced the level of risk to below an acceptable level. Because of the constantly changing nature of the construction site, it is important that these are reviewed frequently and throughout the duration of the construction project.

In order to calculate the risk to the construction site you need to multiply the likelihood of the risk happening by the impact of the risk. 5 is usually used as high likelihood or impact, 1 is usually used as low likelihood or impact. Each risk score should fall into a different category – for example, a score of over 10 being a high risk and should be mitigated, whereas a score of 0 or 1 being of no significant risk. Depending on the scores, you can then decide what to do about the risk. You can either ignore or accept it, you can export or transfer it, or you can address it. There will be a number somewhere along the scale whereby if the risk is below that number action does not need to be taken, but if the risk is above that number something needs to be done. This is known as the “risk appetite”.

Risks can be ignored if the cost of mitigating it is greater than its impact, but only after careful consideration, and just because you are not taking action to combat a risk does not mean that you forget about it. You should still review them when reviewing your entire risk assessment in case the nature of the risk changes.

Exporting or transferring a risk involves taking out insurance or contracting a third party (such as a security company) to mitigate the risk. The third option is addressing the risk, which means using technology, people or processes in order to reduce the likelihood, impact, or both, of a risk, so that the risk appetite is below the acceptable level.

Changing Risk

Because a construction site can be in a constant state of change, the risks can also change very quickly, and therefore it is vital to regularly re-assess the risks and threats to the site. So, before work begins on the site, a risk might be that travellers move on to the empty land and occupy it. However, once work has started, that risk decreases but the risk of theft of materials and equipment escalates.

Combating Risks

In order to reduce the risk to the construction site you need to increase the risk to the potential criminal.

Security solutions should be used in combination to do four things: deter, detect, delay and respond to criminal activity, and most security solutions will provide more than one of these functions.

  • Deterrence – there are many ways to deter a criminal. Whereas an open, unprotected site looks welcoming to a potential criminal, a site with fences, locks, CCTV and security guards will discourage them.
  • Detection – identifying a threat, either at the time to protect vulnerable people and property, or afterwards to identify who carried out the crime.
  • Delay – Any method that can slow the action of the criminal, increasing the chance of them being caught
  • Response – For example, the arrival of security guards or the police

There are six key ways to provide these functions on a construction site, and most construction sites will use some or all of these:

  • Restrict access to the site
  • Protect site assets
  • Surveillance of people on site
  • Provide site safety
  • Provide controlled and monitored site evacuation
  • Liaise with police, local authorities and other stakeholders

It is worth noting that whether a construction site is a green field site or a brown field site will impact on what measures can be used and to what affect in order to combat risk. Green field sites are in effect a blank canvas and provide maximum flexibility when putting in place security. With brown field sites there are often restraints depending on the layout of the existing site.

Types of construction site security

There are two key types of security for construction sites – physical and operational.

Physical measures means infrastructure and includes technical systems such as intruder detection, lighting, CCTV, access control systems, as well as containment measures and obstacles such as fences, gates, barriers and bollards.

Operational measures are human activities, which includes guarding, and carrying out all security operations on site in accordance with the Site Security Policy. This policy should state the requirements of site security and the means and extent of its enforcement. Guarding generally includes patrolling and static guarding, processing people and vehicles in and out of the construction site, managing and operating the technical systems, responding to incidents and liaising with the site manager. Security guards on construction sites must be thoroughly trained and qualified and hold a current Security Industry Authority (SIA) licence.

Some specific ways to help make a construction site more secure include:

Minimise the number of vehicles on site – if only authorised vehicles are on site then it makes it more obvious when other unauthorised vehicles are present. If possible, make all construction workers park off site and enter on foot. Schedule all deliveries in advance and log all access by delivery vehicles.

Restrict the number of people entering the site on foot - keep the number of site entrances and exits to a minimum, install full-height turnstiles and control the entrances with guards or electronic access control measures. There should not be any gaps underneath gates, hinges on gates should be designed in a way to prevent the gate being lifted free, and they should not be able to be used as steps to get over the perimeter.

Plant and vehicles – minimise the amount of plant on site, and outside of working hours move it to a more secure area or cage. Protect windows to stop intruders smashing the glass, take steps to immobilise vehicles or plant, and if practical fit with alarms. Also consider fitting vehicles with tracking devices, and marking and registering all equipment.

Lights – lighting both deters criminals and helps security personnel. All entrance and exits should be illuminated, and lighting should be pointed inwards to show any intruders. The wiring should be protected so that intruders cannot disable the lights.

Hoardings – install hoardings rather than fences around the perimeter as these are more difficult to climb and stop people viewing the construction site inside.

Barriers – barriers such as high kerbs, bollards or trenches might need to be considered if a fence is vulnerable and could be rammed by a vehicle.

Security guards – Larger sites may require 24 hour manned guarding, whereas smaller sites may only need mobile patrols at night.

CCTV – there are a variety of CCTV systems available to deter criminals. Images can be recorded or monitored live, either on site or remotely.

Ladders, scaffolding and stair towers – these are all ways that trespassers can gain access to a site, so measures should be put in place to stop them being used. Ladders should be protected to stop people climbing them, and also to stop people stealing them to access the site in other areas, or to access other sites.

Tools and equipment – small tools should be stored in steel tool vaults with shielded padlocks. Thieves should not be able to remove the vaults.

Building materials – all building materials are targets as they can be sold easily. Metal is a particularly high value target, so hide cables and copper tubing away from view and store in locked containers.

Fuel – fuel stores and fuel in vehicles needs to be protected


This article has aimed to provide an overview of some of the security risks that can affect construction sites and ways to combat them but it is no means intended to be an exhaustive list. Whilst it is important to remember that it is practically impossible to protect a construction site from every conceivable threat, there is a much higher chance of doing so if site managers make use of security professionals to give expert advice about security measures and provide solutions.

Kingdom’s dedicated civil engineering and construction team has extensive experience and an in-depth understanding of the construction sector. They maintain an inventive but orderly approach to construction projects and offer a flexible range of services and solutions that make a difference. For more information about Kingdom’s civil engineering and construction security services, please visit or call 0845 051 7702.

Kingdom Partners

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