According to specialist landlord insurance providers there has been a surge in landlords making insurance claims over the past year or so - with claims averaging a whopping £40,000. This is because tenants have destroyed properties whilst using them to grow cannabis.

Of course, from the outside of a property that is harbouring Cannabis production facilities, it may all look pretty normal - the house looking much like any other in the street, but inside it will resemble a forest of Cannabis, electrical wires and pipes.

The main damage landlords will be left to restore after letting their property to Cannabis-growing tenants are:

• Contents and floors stripped
• Soil stored under floor boards
• Wiring cut into to bypass electricity meters
• Irrigation system installed
• Heating system installed
• Generators installed
• Damage to walls as a result of installations
• Mould, residue and damp
• Loft space used, often leading into neighbouring roofs if in a terraced house

The most shocking fact about landlord's properties being used on a professional drug growing basis is that a house can be completely strippedso it is unrecognisable as a home. Often the tenants have left before the landlord has even noticed a problem, leaving the landlord to restore the property completely before they can re-let to new tenants.

These types of criminals can be very sophisticated and fast moving. However there are simple ways that a landlord can prevent their property being used to grow Cannabis.

Click here to read the full article on keeping illegal drugs out of rental properties including a comprehensive list of the signs of drug activity in property.

It is always important for landlords to be vigilant in their approach to letting properties to potential tenants. Always ask for references - both financial and personal and make sure that you follow these references up. Tenants may seem genuine, but it has been proved on countless occasions that first impressions do not count. As a landlord you could also include routine property checks in your contract or rental agreement - many landlords do not enter the property fr 6 - 12 months after the start of a let, afterwhich the culprits will have usually left.

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