Around 115 years old, the British Standards Institution’s Kitemark is awarded to services and products which meet its exacting and thorough standards of quality, safety and reliability. This certification is most frequently given to any product relating to public safety, from fire alarms to electrical plugs.

Most crucially to us here at Banham, however, are the standards that apply to door locks; specifically, the BS3621 lock standards, put in place and enforced by the BSI, which the majority of our products meet. But does it matter if your current locks don’t meet these standards, and what does it mean to have a BS3621 lock in the first place?

What are BS3621 locks?

BS3621 is the basic BSI standard which the locks on your ground floor exterior doors need to meet in order to comply with any home insurance policy. Although the interior doors of your property may not need BS3621 locks, the exterior doors of your property absolutely do, not only for insurance purposes, but to delay and prevent intruders from accessing your home.

Mortice and cylinder rim locks are the two lock varieties which need to meet BS3621 lock standards, all of which are related to their design. For multipoint locks, the equivalent standards are dubbed PAS3621, but rest assured they are equally safe.

To comply with BSI standards, BS3621 locks are designed to adhere to the following criteria:

• A BS3621 mortice lock must have at least five-lever or pin tumblers.

• Screws which fix the lock or cylinder to the door must not be accessible when the door is shut.

• The lock must be covered by a hardened metal plate in order to prevent intruders from being able to drill it.

• The bolt must protrude from the faceplate by a minimum of 20mm when the door is locked.

• When activating the lock, the bolt must be completely activated before a key can be removed.

For more information, visit our guide on the different types of door lock.

How can I tell if my locks meet the BS3621 standard?

There are a few visual signs that can help you determine whether your current locks are compliant with the standard. BS3621 locks will have the trademarked BS kitemark on the faceplate—the metal part of the lock which cannot be seen when the door is closed.