The fire safety dangers of cannabis farms

As the market for cannabis continues to grow illegal production facilities with their modified electrics and intense lighting pose a serious fire hazard

Author: Paul Redington

13 June 2020

In the UK, statistics from the Home Office show that more than a third of a million cannabis plants were seized in 2018. The West Midlands alone saw 67,776 plants confiscated, an increase of almost 40 per cent on the year before. That same year the Metropolitan Police revealed that one cannabis farm was found every couple of days in London.

While 2019 figures are awaited, the UK emergency services have been attending cannabis-related fires since at least the 1970s. But as cultivation increases so does the number of fires related to illegal factories or farms.

Figures released by London Fire Brigade show there were 12 cannabis factory fires in the capital in the first four months of 2019 alone, approaching the total for the whole of 2018. Many of these fires are in residential premises posing a serious threat to those living nearby, but fires in cannabis factories in commercial premises are also becoming more prevalent. What's behind these increases?

"The UK is the world's largest producer and exporter of legally cultivated cannabis"

First the demand for cannabis itself appears to be increasing. With a greater focus on medicinal use, some well-known high-street retailers are selling legal products based on cannabis oil; in fact the UK is the world's largest producer and exporter of legally cultivated cannabis. With demand on the rise and coming from a wider customer base than before, a ready market has also been created for illicit production and distribution.

Second, this market means large-scale illegal cannabis production is big business for those involved. There is good evidence that many factories are part of established criminal networks with many thousands of people involved in the supply chain of this lucrative trade.

Third, much more information about cultivation is now available and the equipment to start even a small factory is quite easily obtained via the internet. This means that some may begin growing the drug in a back bedroom purely for personal use, for example, and not necessarily to sell on.

What's clear is that the production of cannabis in the UK is on the rise and in turn we can probably expect related insurance claims to continue heading in the same direction. Although insurers do not collect specific statistics on fire claims related to cannabis production there is good evidence that they are currently seeing more losses relating to these factories and that those claims are becoming larger.

A large warehouse blaze in Tottenham in May 2019 is believed to have started in one unit that was being used to produce the drug.

The fire burned for more than 24 hours and took 100 firefighters to extinguish. Zurich insures one of the neighbouring units with the resultant claim by the innocent customer costing more than £1m. The damage was widespread.

And it's not just fire that's an issue with cannabis factories: damage related to leaks from irrigation systems is also prevalent, as are problems resulting from condensation in the building fabric caused by the humid environment that a factory may create. Holes are sometimes cut in ceilings to provide ventilation or to enable access for wiring which in itself is often substandard.

Where a fire does occur, it is often due to the temporary lighting and heating equipment that has been rigged up in the premises. High-powered industrial lamps are often used and they produce significant heat, with all the associated risks. In turn, any electrically-powered ventilation system that may be required creates additional hazard if not installed properly. Finally, all this set-up requires considerable energy and cabling. Most of this is poorly installed and subject to potential short circuits and resistive heating faults that can easily cause wiring or any combustible materials around it to ignite.

Insurers such as Zurich continue to work with property-owning customers and their advisers to guide them on steps that can be taken to protect premises and reduce the chances of them being a victim of an unscrupulous occupier. Reputable property owners can easily fall victim to a tenant or subtenant who decides to set up a cannabis factory, meaning it is crucial that landlords have a robust vetting system. Tell-tale signs may be tenants who seek to pay rent in large sums of cash or are unable to supply proper references. Failing to conduct proper checks on prospective tenants can even mean a property owner is in breach of an insurance policy condition.

"Damage related to leaks from irrigation systems is also prevalent"

Vacant premises are also an issue. In some cases they have been broken into and used as cannabis farms without the knowledge of the owner. Once established the farms themselves are then left largely unattended, meaning any fire that may develop is not dealt with until it takes hold. Fires are often only spotted by neighbours or passers-by, increasing the level of damage to the premises itself and the threat to adjacent buildings.

It is therefore vital that empty premises are properly secured and visited regularly, with careful internal inspections where possible, as external inspection alone may give no indication as to what is going on inside. Neighbours may see very little coming or going either, so factories can remain undetected for months if not for a longer period.

The risks associated with illicit cannabis farms are clear, with fire being the most obvious hazard. It is a problem that shows no signs of abating. Those who own and manage property need to take appropriate steps to avoid becoming a victim of something that is a growing issue for both them and their insurers.

Gary Strong RICS global building standards director comments: "Cannabis farms and damage from fires and illegal occupiers are issues RICS professionals need to be very alert about and regular inspections of vacant property are essential. If adjacent property is also observed to be suspected of being used for a factory  this should be reported to the police."

Paul Redington is a regional property major loss manager at Zurich Insurance  paul.redington@uk.zurich.com

Related competencies include: Fire safety

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