Securing your doors and windows

Securing your doors and windows

Going away this Easter?

Home security is one of the key considerations that we think about when protecting our homes, especially if we are unlucky enough to have ever been on the receiving end of a break-in.

Despite being an overused cliché, the feeling can only ever be described as ‘gut-wrenching’ and anyone who has been burgled will understand (myself included). The material ‘stuff’ that’s taken is usually replaceable and ultimately that is what insurance is there for, but the one thing insurance can not rectify is the violation of your personal space and losing anything of sentimental value.

Put simply, the best way to avoid a break-in (and thus a claim on your household insurance) is to make your home hard to break into. If an ‘organised thief’ is specifically targeting your artwork or jewellery they will usually find a way into your home, regardless of how good your locks and alarm system are. Good security, however, will stop the ‘chancer’ by putting a couple of simple barriers in their way which we’ll explore. Both the security and insurance industry are full of technical wordings so please find some jargon-busting below:

5-Lever Mortice Deadlocks

What is a 5-Lever Mortice Deadlock?

  • These locks are normally half way down the door and close to the handle. The lock is morticed (built in) to the door itself and a rectangular shaped bolt is thrown to a reinforced gap in the door frame. The number of levers refers to how many levers operate inside the lock to throw the bolt (normally 3-lever, 5-lever or 7-lever).

Why do I need a 5-Lever lock?

  • Essentially, they are harder to pick. The more levers internally within the lock, the harder it is to get past.

How can I tell if I have a 5-lever lock?

Opening the door and looking at the thin edge will reveal the face plate of the lock. On this faceplate it will normally state 5-levers or BS3621. BS3621 refers to the British Standard reference that insurers use to determine whether a lock is easy or difficult to pick.

British Standard 3621

This is the most commonly referred to standard for locks and there are certain standards that the lock has to adhere to before being awarded the Kite Mark:

  • Withstand attack for 5 minutes from drilling or cutting with standard tools

  • Mechanism to resist manipulation (picking) known as a keyway shroud

  • At least 1,000 key variations for the particular type of lock

  • Bolt must project at least 2cm into a steel keep

  • Withstand certain sideways-force tests

  • Some insurance policies require that these are in place so do check your policy documents or if you are insured with Lark, you can contact your Account Handler to check.

Multi-Point Locking System

  • These can be found either in wooden or UPVC doors and are normally operated by pulling the handle upwards to move multiple ‘points’ on the door that secure the door to the frame when shut. These are normally found on more modern doors and are normally found in conjunction with a lock barrel that conforms to BS3621.

Key Operated Window Locks

  • What is says on the tin… these are window locks operated with a key. There are a number of variants of window locks, whether these are operated with an allen key, or a traditional key, they are all deemed to be key locks. The reason for these is that they make windows harder to jimmy, force, or tease open than if they are just secured with a latch. For some older period and listed properties, it can be more difficult to install these and there is an argument that if the property has leaded or single paned windows, they are of limited use as these types of windows are easily broken.

  • Different insurers approach window locks differently so it is worth checking that your locks comply with your insurer’s requirements. If they do not, it may be worth looking to move insurers as your policy may not respond properly in the event of a claim. If you are insured through Lark, you can verify with your account handler that we hold the correct information on file.


  • Audible warning alarm – these are relatively simple to install and maintain under an annual maintenance contract and will sound a siren if an intrusion is detected. Some insurers will require your alarm to be installed by a NACOSS or NSI approved installer.

  • Central station alarm – these alarms can have a siren, but will contact a central monitoring station or police station who will contact you to see if the alarm is genuine and they physically will attend your property. Different providers offer different levels of service so it is important to check exactly what you are getting. These are ideal for homes in a remote location, frequently unoccupied, or have particularly high levels of attractive items, such as artwork and jewellery at the premises. 

  • Alarms should be considered as additional security to door and window locks, rather than something to have instead of the physical deterrents. Although alarms have their place they will not stop someone entering the property, whereas door and window locks will

Other security features

Some standard market insurers have a tick-box system whereby if the security does not meet their requirements the policy may be restricted or the insurer may cancel the policy altogether. If this is the case it is worth moving to a different insurer who will take other security features into account, such as daytime occupancy, CCTV, walled or gated premises, remote locations or simply living in a low theft area.

At Lark, we pride ourselves on providing ‘made to measure’ solutions tailored to you and ensure that our panel of insurers follows the same ethos by taking other security features into account. So if you are insured with us and have any concerns or would like any security advice, please contact your Account Handler.