How to Protect Your Commercial Premises from Arson
Arson is one of the most common causes of serious fires in UK commercial premises — and unlike accidental fires, it is largely preventable. The measures that deter arsonists are, for the most part, straightforward, inexpensive, and well within the reach of any responsible person who understands where the risk actually comes from.
Deliberate fire-setting is a persistent problem across the UK's commercial and industrial building stock. Home Office data shows that hospitality premises alone recorded close to 400 arson incidents in a single year, and across the broader commercial sector — warehouses, offices, retail units, schools, places of worship, and vacant buildings — deliberate ignition accounts for a significant proportion of the most serious and damaging fires that occur. Unlike the accidental fires that arise from electrical faults, cooking equipment, or hot works, arson fires are rarely random. They exploit specific conditions: easy access, poor visibility, unmanaged combustible materials left in exposed locations, and the absence of any meaningful deterrence.
This means that most arson attacks can be prevented, not by sophisticated security infrastructure, but by understanding how arsonists select their targets and systematically removing the conditions that make a premises attractive to them. A fire risk assessment that treats arson as a credible ignition source — rather than an edge case too unlikely to plan for — is the foundation on which an effective prevention strategy is built.
Who sets fires, and why it matters for prevention
Understanding the profile of those who set fires deliberately is not merely academic — it shapes the kind of preventive measures that are likely to be effective. Arson is committed across a wide spectrum of motivations and circumstances, and the controls that deter one type of arsonist may have little effect on another.
A significant proportion of deliberate fires at commercial premises are set opportunistically, often by young people, and often in locations that offer easy access to combustible material — waste bins, stored packaging, unattended pallets — combined with low visibility and minimal risk of being seen. For this category, which accounts for a large share of incidents at retail premises, warehouses, and commercial yards, relatively straightforward environmental changes are highly effective: removing or securing combustible materials, improving lighting, eliminating blind spots, and making the site feel overlooked and managed rather than neglected and anonymous.
A smaller but more damaging category involves targeted arson — fires set against a specific business, often in the context of a dispute, a grudge, or organised crime. These fires are harder to prevent purely through environmental measures, and may require a different response, including liaison with police and consideration of how the business manages access to information about its operations and staff.
Vacant and partially occupied buildings attract a third category of risk — fires set by trespassers using the building for shelter or other purposes, or by those who regard empty premises as low-risk targets. The fire risk in vacant commercial buildings is consistently underestimated by building owners, who sometimes assume that an empty building presents less risk than an occupied one. In practice, the combination of unmonitored access, accumulated combustible debris, and the absence of any deterrent presence makes vacant buildings among the most vulnerable of all commercial property types.
Where arson risk concentrates on a commercial site
Arson risk on a commercial premises is rarely evenly distributed. It tends to concentrate in specific locations that share a common set of characteristics: easy access from a public area, low visibility from inside the building or from the street, and the presence of combustible material that can be ignited quickly and will sustain a fire long enough to involve the building structure. Identifying these locations is one of the first steps in an arson prevention review, and it is an analysis that should be built into every fire risk assessment.
The most consistently high-risk locations across commercial premises of all types include the following.
Bin stores, skips, and waste compounds are among the most common points of fire origin in deliberate attacks on commercial premises. They combine combustible material with, typically, a location at the rear or side of the building, away from direct surveillance. A fire started in a plastic bin store positioned against an external wall can involve the building within minutes.
Delivery yards, service roads, and rear access areas are frequently designed for operational convenience rather than security or surveillance. They often have multiple access points, limited lighting, and a combination of stored materials — pallets, packaging, gas cylinders, waste — that provides ready fuel for a deliberately set fire.
Disused storerooms, unlet units in a multi-occupancy building, basement areas, and rooftop spaces that are rarely visited are all attractive to trespassers and to those looking for a location that is unlikely to be discovered quickly. A fire in a disused part of a building may burn undetected for longer than a fire in an occupied area, significantly increasing the damage caused before suppression begins.
Boundaries where the building or its external materials are accessible from a public pavement, car park, or alleyway allow an arsonist to set a fire without entering the property at all. External cladding, timber fencing adjacent to the building, or combustible materials stored against an external wall all present this vulnerability.
Refurbishment sites concentrate risk: they accumulate significant quantities of combustible materials — timber, insulation, packaging — at a time when the building's fire protection systems may be compromised or out of service, normal occupancy has been disrupted, and access control is often more permeable than usual. Fire risk assessments for buildings undergoing significant works should explicitly address the temporary increase in arson risk.
The consequences of a serious arson fire
The scale of destruction that a deliberately set fire can cause to a commercial premises in a short period is difficult to convey in abstract terms. The BBC report below, covering a major arson attack on a commercial site in Greater Manchester, illustrates the point directly.
The pattern is consistent with what fire investigators find across commercial arson cases: a fire started in an accessible perimeter location, involving combustible materials, that spreads rapidly into the building structure before detection and suppression can contain it. The financial cost runs into hundreds of thousands of pounds in even relatively modest incidents; in larger buildings, the loss of the structure itself, combined with business interruption, loss of stock, and the impact on employees and supply chains, can be devastating and permanent.
For responsible persons managing warehouses and industrial premises, where fire loads are high and buildings may be unoccupied overnight, the potential consequences of a serious arson fire are particularly severe. For managing agents with responsibility for multiple commercial properties, the cumulative exposure across a portfolio warrants systematic attention to arson prevention as part of their broader fire safety management obligations.
Controlling combustible materials and waste
The single most effective arson prevention measure available to most commercial premises is also one of the simplest: controlling the combustible material that is available at vulnerable locations. An arsonist who cannot find readily ignitable material in an accessible location will either move on or, if they are determined, will need to bring their own accelerant — a significantly higher level of commitment that substantially reduces the pool of potential attackers.
The key controls are straightforward in principle, though they require consistent management discipline to maintain in practice. Bins and skips should be positioned as far from the building as the site allows — a minimum of six metres is the guidance commonly cited, though any increase in distance from the external wall reduces the risk of fire spread into the structure. Where this is not possible because of site constraints, metal bins with lids should replace plastic containers, and the area should be enclosed behind secure lockable gates. Waste should be cleared regularly rather than allowed to accumulate, and the practice of leaving packaging, pallets, or other combustible material outside at the end of the working day — common on busy commercial and retail sites — should be actively managed out.
External storage areas more broadly should be reviewed with the same lens. Gas cylinders, LPG tanks, and other hazardous materials stored outside present not only an arson target but a potential explosion risk if fire reaches them. Their positioning relative to the building, and the security of the enclosures that contain them, should be addressed specifically in the fire risk assessment.
A common findingOn many commercial sites, combustible waste accumulates at the rear of the building without anyone consciously deciding it should be there. Pallets are left after a delivery. Packaging is moved outside to clear space inside. Over weeks and months, a significant fuel load builds up directly against an external wall, at the point of the building least visible from inside or from the street. This is one of the most common arson vulnerabilities we identify in fire risk assessments, and one of the easiest to address.
Security, lighting, and natural surveillance
Arsonists — particularly opportunistic ones — are deterred by the perception that they are visible and may be challenged or identified. Environmental design that increases the sense of oversight over vulnerable areas of a site is therefore one of the most powerful preventive tools available, and it does not require expensive technology to achieve.
Adequate external lighting is the most fundamental element. Areas that are dark at night — rear yards, service roads, bin compounds, car parks — should be lit to a standard that makes anyone present clearly visible from a distance. Motion-activated lighting has the additional advantage of drawing attention to movement in areas that are not normally active after hours, and may deter someone who assumes the site is unwatched. Lighting that is poorly maintained, with bulbs left unrepaired for extended periods, sends a message about the level of management attention applied to the site more broadly.
CCTV is a useful complementary measure, but its effectiveness depends on how it is configured and monitored. A camera system that covers the front of the building while leaving the rear yard unmonitored addresses only the most visible part of the site, not the most vulnerable. Cameras should be positioned to cover the locations identified in the arson risk review as highest priority, and signage indicating the presence of CCTV should be clear and visible from the approaches to those areas. Where monitoring is passive — footage reviewed only after an incident — the deterrent value is lower than where monitoring is active or where the system is linked to a monitoring centre.
The physical security of the site perimeter matters both for preventing access and for demonstrating that the premises is managed and cared for. Damaged fencing, broken gates, insecure doors at the rear of the building, and unrepaired access points all signal that the site may be an easy target. Prompt repair of damage, and regular inspection of perimeter security as part of routine site management, removes that signal and reduces the likelihood of the site being selected.
Managing vacant and partially occupied premises
Vacant commercial buildings — whether empty between tenants, in the process of being sold, or awaiting development — carry a substantially elevated arson risk that building owners and managing agents frequently underestimate. The absence of regular occupancy means there is no natural surveillance, maintenance issues can go unnoticed, and the building may attract trespassers whose activities introduce fire risk independently of deliberate arson.
The management of vacant commercial property should include, at minimum, regular physical inspections of the building and its perimeter, prompt boarding or reinforcement of any vulnerable access points, removal or securing of any combustible material from inside and immediately outside the building, and maintenance of at least basic utility supplies to allow heating and lighting to function. Premises left completely cold and dark over extended void periods are more likely to suffer from burst pipes, structural deterioration, and the accumulation of moisture conditions that make the building progressively harder to bring back into use — and more vulnerable to fire in the interim.
Where a building is going to be vacant for an extended period, specialist vacant property insurance and risk management services exist to provide regular inspection and monitoring. The cost of these services is typically small relative to the potential loss from a fire in an unoccupied building, and insurers will often require them as a condition of cover.
For managing agents with vacant units within otherwise occupied multi-tenancy buildings, the risk from those vacant spaces to the rest of the building's occupants should be explicitly addressed in the building-level fire risk assessment. A vacant unit that provides access to a shared escape route, or that is adjacent to occupied demises without adequate compartmentation, is a risk not just to the vacant space itself but to every other occupier in the building.
Detection, alarm, and out-of-hours response
Even where prevention measures are well implemented, detection and early-warning systems remain a critical backstop. Most arson fires at commercial premises occur outside normal working hours, when the building is unoccupied and the time between ignition and discovery is at its longest. The adequacy of the fire detection system for out-of-hours incidents deserves specific attention in the fire risk assessment, and the monitoring and response arrangements for out-of-hours alarm activations should be tested rather than simply assumed to be working.
Detection coverage in the locations identified as highest arson risk — rear yards, bin compounds, plant rooms, vacant areas — should be specifically reviewed. A detection system designed primarily for daytime occupancy may have gaps in coverage of precisely the areas where an out-of-hours arson attack is most likely to start. External detection, while less common than internal systems, may be warranted on sites where the perimeter locations are identified as high risk and where rapid spread from an external fire to the building structure is a credible scenario.
The monitoring of the alarm system — whether via a Alarm Receiving Centre, a security company, or an arrangement with keyholders — determines how quickly a fire service response is initiated once a fire is detected. A system that relies on a single keyholder being available and responsive introduces delay into the response chain that, in a fast-developing arson fire, can be the difference between a contained incident and the total loss of the building. These arrangements should be reviewed and documented as part of the overall fire safety management framework.
Staff awareness and reporting culture
Many arson attacks are preceded by reconnaissance, testing, or minor incidents that, if noticed and reported, might allow preventive action to be taken before a serious fire occurs. Staff who notice that bins have been interfered with, that access gates have been forced, that strangers have been loitering in rear areas, or that minor fires have been set and self-extinguished are a valuable source of intelligence — but only if they know that reporting these observations matters and that someone will act on them.
Building this awareness into fire safety training is straightforward, and it costs nothing beyond ensuring that the topic is covered and that the reporting mechanism is clear. Staff should know who to contact if they observe suspicious behaviour, that seemingly minor incidents such as a fire in a bin or interference with a gate should be reported rather than dealt with informally, and that the business takes these matters seriously. For office and commercial premises with reception or security functions, these staff are often in the best position to observe and report early warning signs, and their training should specifically address this.
Arson prevention as part of the fire risk assessment
Arson prevention should not be treated as a security matter that sits separately from fire safety management. It is an integral part of a complete fire risk assessment, and a responsible person who has not considered deliberate ignition as a credible fire source has not produced a suitable and sufficient assessment. The FSO requires the responsible person to identify all sources of ignition, and there is no principled basis for excluding the most common cause of serious commercial fires from that analysis.
In practice, incorporating arson into the fire risk assessment means identifying the locations on the site that are most vulnerable, the combustible materials in those locations that would provide fuel for a deliberately set fire, the adequacy of the access control and surveillance measures that currently exist, and the detection and response arrangements that would limit the consequences of a fire that does occur. The resulting action list should include both the physical measures needed to reduce the attractiveness of the site as a target and the management practices — waste control, site inspection, staff training — that keep those physical measures effective over time.
For premises in sectors where arson risk is consistently elevated — warehouses and industrial sites, schools, churches and places of worship, hotels and hospitality venues, and HMOs — the arson component of the fire risk assessment deserves particular attention and should be reviewed whenever there are changes to the site, its use, or the local environment that might affect the risk profile.
Key principleMost arson attacks succeed because of opportunity, not sophistication. The arsonist who sets fire to a commercial premises has typically chosen it because it offered easy access to combustible material with a low risk of being seen or identified. Remove those conditions and most arsonists move on. The measures required to do so are, in the majority of cases, proportionate, affordable, and well within the capability of any diligent responsible person.
A review checklist for responsible persons
The following covers the main areas that a responsible person should review when considering arson risk across a commercial premises. It is not a substitute for a professional fire risk assessment, but it provides a practical starting point for identifying the most significant vulnerabilities.
Are bins and skips positioned away from the building? Are they metal with lids, or plastic and open? Is combustible waste cleared regularly? Are pallets, packaging, or other materials left outside at the end of the day?
Are all gates, doors, and access points to rear and service areas secured outside working hours? Is damaged fencing or broken hardware repaired promptly? Are there points at which the building or combustible external materials can be reached from a public area?
Are vulnerable areas — rear yards, bin compounds, service roads — adequately lit at night? Is CCTV coverage aligned with the highest-risk locations rather than just the most visible ones? Is signage indicating CCTV clear and visible?
Are vacant units, disused storerooms, or unoccupied parts of the building inspected regularly? Are access points to these areas secured? Has the fire risk assessment addressed the risk these areas pose to the building as a whole?
Does fire detection coverage extend to the locations most likely to be targeted by an arsonist? Are monitoring and response arrangements for out-of-hours alarm activations tested and documented? Is there a clear procedure for responding to an out-of-hours alarm?
Do staff know to report suspicious behaviour, interference with site security, or minor fire incidents? Is this covered in fire safety training? Is there a clear reporting mechanism that staff understand and use?
Does the current fire risk assessment explicitly address arson as a credible ignition source? Has it been reviewed following any changes to the site, its use, or the local environment? Are the arson-specific actions from the assessment being followed up?
Fletcher Risk Management carries out fire risk assessments across Chester, Cheshire, the Wirral, North Wales, Merseyside, Warrington, and the wider North West, across all commercial and industrial building types. Arson risk is addressed as a standard part of every assessment we carry out. If you manage a warehouse or industrial site, a school, a church or place of worship, a portfolio of managed commercial properties, or any other premises where arson is a credible risk, we are well placed to help. Further details of our coverage area and the sectors we work in are on our website, and you can reach us through our contact page.
Is arson risk properly addressed in your fire risk assessment?
Fletcher Risk Management works with businesses, managing agents, schools, and landlords across Chester, the Wirral, Merseyside, and the North West. If arson has not been explicitly considered in your current assessment, or if your assessment is overdue, please get in touch.