A burglary claim can become more complicated when an insurer finds that the locks on a door did not meet the policy conditions. This guide to burglary insurance locks explains what insurers commonly look for, where homeowners get caught out, and how to make sensible improvements without replacing locks that are still doing their job.
The first step is not buying the most expensive lock on the shelf. It is checking your policy wording, identifying every external door and accessible window, and making sure the security on each one matches the risk. A solid lock on the front door is useful, but it will not help much if the side entrance has a worn-out cylinder or the patio doors do not lock correctly.
What are burglary insurance locks?
There is no single lock called a burglary insurance lock. The phrase usually means a lock that meets the minimum security standard set out in a home insurance policy. In the UK, insurers often refer to British Standards, lock types, or a requirement for suitable locks on all outside doors and ground-floor windows.
Older policies may specify a five-lever mortise deadlock to BS 3621 on a wooden front or back door. Other policies use broader language, such as requiring an approved mortise deadlock, multi-point locking, or key-operated window locks. Modern uPVC and composite doors normally use a multi-point mechanism with a euro cylinder, so the quality of the cylinder matters just as much as the handles.
Do not assume a lock is acceptable because it came fitted to the door. Builders, previous owners, and landlords may have chosen basic hardware, and standards change over time. Your policy wording is the final authority. If it is unclear, ask the insurer to confirm what is required in writing.
Start with the policy, not the lock
Insurance documents can be dry reading, but a few minutes spent checking the security section can prevent an expensive surprise. Look for conditions covering forced entry, security when the property is empty, the type of locks required, and whether windows must be secured with keys.
Pay close attention to doors described as “external.” This can include a door from an attached garage into the house, a side utility door, a conservatory door, or a door leading from a shared corridor. If someone could use that door to enter your home, it deserves the same attention as the front door.
It also matters how you use the property. A standard policy may have different conditions if the home is vacant for an extended period, rented out, used as a holiday let, or left unattended during renovation work. Insurance requirements are not always one-size-fits-all.
Common lock standards you may see
BS 3621 for mortise deadlocks
BS 3621 is a common standard for key-operated mortise deadlocks, often fitted to timber doors. A proper five-lever deadlock has a bolt that is thrown into the frame with a key. It is different from a simple latch, which can sometimes be bypassed if the door and frame are weak or the latch is not secured.
A BS 3621 lock is usually marked on the faceplate or lock body. It may carry the British Standard kite mark as well. If you cannot see a marking, that does not automatically mean the lock is unsuitable, but it is worth having it checked rather than guessing.
Multi-point locks and euro cylinders
Most modern uPVC and composite doors use a handle-operated multi-point system. When the handle is lifted, hooks, rollers, bolts, or mushrooms engage into keeps in the frame. Turning the key then locks the mechanism.
The weak point is often the cylinder. Older standard cylinders can be vulnerable to snapping, drilling, or picking depending on their design and installation. A suitable upgrade may be a TS 007 three-star cylinder or a one-star cylinder used with two-star security handles. The right choice depends on the door, handle arrangement, and the insurer’s requirements.
A cylinder should sit correctly in the handle. If it projects noticeably beyond the door furniture, it may be easier to attack. This is a common issue after a door has been fitted with the wrong cylinder length.
Rim locks and night latches
A night latch can be convenient for everyday use, especially on a timber front door, but it may not meet an insurer’s requirement on its own. Some homes need a BS 3621 deadlock in addition to the night latch. A lockable, higher-security rim cylinder can improve a night latch, but it does not necessarily replace the need for a deadlock under your policy.
Windows and patio doors
Ground-floor and easily accessible windows may need key-operated locks. The same can apply to basement windows, garage windows, and windows near flat roofs, drainpipes, or extensions. Keep the keys nearby for emergency escape but not on the sill or in a place visible from outside.
For patio and French doors, check that the handles lift properly, the mechanism engages fully, and the doors cannot be pulled apart from the frame. A stiff handle is not just an annoyance. It can be a sign that the door is out of alignment, putting strain on the locking mechanism and leaving it partly engaged.
A practical guide to burglary insurance locks by door type
A timber front door often needs a mortise deadlock, a good-quality night latch, or both. The condition of the frame, strike plate, and screws matters too. A strong lock fixed into soft, split timber is only as secure as the frame around it.
For a uPVC or composite door, test the multi-point lock with the door open and then closed. Lift the handle fully, turn the key, and make sure it operates smoothly. If you have to push, pull, or lift the door hard to lock it, do not ignore it. Misalignment can cause a mechanism to fail, sometimes leaving you locked out or unable to secure the door.
For a sliding patio door, look beyond the central lock. Anti-lift blocks, secure tracks, and locking points at the top and bottom can all matter. For a garage-to-house door, fit the lock standard your insurer expects even if the garage itself has a separate up-and-over door. Once an intruder reaches an internal connecting door, that door becomes a key line of defense.
Avoid the mistakes that can affect a claim
The most common problem is leaving a door unsecured because it appears closed. A multi-point door is not fully locked until the handle is lifted and the key is turned. Pulling the door shut may engage the latch, but it does not activate the hooks or bolts.
Another issue is key management. Leaving a key in the inside of a door can be convenient, but whether it is sensible depends on the door design and nearby glazing. If someone can break glass and turn or remove the key, they may be able to open the door. On the other hand, removing every key from an exit can slow escape in an emergency. Consider security and fire safety together.
Do not make changes after a break-in without documenting the damage first, unless the property needs immediate securing. Take clear photographs, keep damaged parts where possible, and obtain any crime reference number requested by the insurer. Emergency boarding or lock replacement may be necessary, but a clear record helps show what happened.
Finally, do not rely on a standard printed on the box alone. The lock must be fitted correctly. Incorrect screw lengths, poor alignment, loose handles, a weak frame, or a badly sized cylinder can undermine a decent product.
When a lock upgrade makes sense
An upgrade is sensible when your policy requires it, the existing lock is damaged, keys have been lost or copied without your control, or the door hardware is clearly dated. It is also worth considering after moving into a new home. You do not know how many previous keys are in circulation, and changing cylinders is often a straightforward way to take control of access.
There are trade-offs. High-security hardware costs more than a basic replacement, and not every door needs the same level of upgrade. A qualified locksmith can assess the full door, frame, mechanism, and lock rather than simply fitting the most expensive cylinder available. For homeowners in Melksham, Trowbridge, Bath, and the surrounding area, GHI Locksmiths can explain the options in plain language and fit a lock that suits the door as well as the policy.
If you are unsure whether your locks meet the wording of your insurance, take a photo of each external door lock and the relevant policy section before making a decision. A quick professional check is usually cheaper and less stressful than finding out there was a security gap after something has gone wrong.