Landlords are facing substantial financial losses from illegal cannabis cultivation operations, with insurers reporting £9.4 million in claims since January 2022, according to new data from Zurich UK.
The insurer analysed 17 cannabis farm-related claims over the period, revealing a pattern of extensive property damage that leaves buildings unsafe and requiring six-figure repair costs before they can be reoccupied.
Fire service callouts increase 218%
Fire and rescue service callouts to suspected or identified cannabis farms rose 218% between 2015 and 2024, climbing from 17 incidents to a record 54. Last year saw 50 attendances recorded, maintaining near-peak levels.
Freedom of Information data obtained from 21 fire and rescue services shows incidents rose 59% between 2019 and the 2024 peak. Home Office analysis puts the national figure at 640 cannabis farm fires between 2019 and 2024.
South Wales emerged as the most affected region, with fire crews attending 90 suspected cannabis farms over seven years and a peak of 25 incidents in 2020. Essex recorded 56 attendances during the past decade, followed by Hereford and Worcester with 55.
Property damage and repair costs
Zurich’s investigators have found commercial units extensively altered to support cultivation, with electrical systems tampered with to meet energy demands. The modifications result in landlords facing extended vacancies and substantial repair costs before buildings can be safely reoccupied.
Claims typically involve dangerous electrical alterations, extensive water damage from irrigation systems, widespread damp and mould, and significant structural changes made to conceal growing operations. Similar to other challenges facing landlords, by the time a property is recovered, owners can face months of disruption and repair bills running into hundreds of thousands of pounds.
Scott Clayton, Head of Claims Fraud at Zurich UK, said the profile of these operations has changed. “Many landlords still picture cannabis farms operating in remote industrial estates or hidden warehouses. What we’re increasingly seeing is organised criminal groups targeting empty shops, offices and retail premises, often hiding in plain sight on high streets across the UK.”
Warning signs for landlords
Zurich identified several warning signs at the letting stage, including tenants willing to pay the asking rent without negotiation, reluctance to involve solicitors on high-value leases, requests to remove inspection clauses, and newly incorporated companies with little financial history.
During tenancy, indicators include businesses that never appear to trade, repeated avoidance of inspections, blacked-out windows, external ducting fitted without permission, strong unusual odours and unexplained alterations to electrical systems.
Clayton added: “These operations can involve sophisticated attempts to present a legitimate business front, making it difficult for landlords to spot the warning signs until significant damage has already been done.”
The data suggests landlords face increasing risks from organised criminal activity targeting rental properties, with financial implications extending beyond immediate repair costs to include extended void periods and potential insurance complications.
