A nightlatch is a surface-mounted lock that is normally fitted to timber front doors in the UK. In contrast to a mortice lock, which is installed inside the door, a nightlatch is mounted on the inside surface and operates using a latch mechanism that automatically locks when the door is shut. They are sometimes called “Yale locks” — after the company that made them popular — though many companies now make them.
There are two principal types: standard nightlatches and deadlocking nightlatches. The standard type lets the door be opened from the inside whenever, through a handle or knob. Deadlocking types, on the other hand, permit the latch to be fully locked with a key, so that the internal handle won’t function until it is unlocked again. This provides an extra level of security, particularly for doors next to glass panels where a handle might be accessible from the outside.
Nightlatches are usually fitted in conjunction with other locks, for example a British Standard 5-lever mortice deadlock, to satisfy requirements for home insurance and enhance door security in general.
Where Nightlatches Are Most Commonly Used
Nightlatches occur primarily on front entrance doors of houses but are also installed in multi-occupation buildings such as maisonettes and flats, where doors should automatically lock behind individuals when they leave or arrive. Their auto-locking functionality makes them an ideal pick for daily use.
They’re especially helpful in households with small children or senior residents who might forget to lock up by hand. Because the latch engages when the door closes, there’s no reminder to turn a key each time you leave home.
With that in mind, nightlatches must never be used as a sole lock on the front door. Although convenient for locking and unlocking quickly, they are not the same level of protection found in a properly fitted mortice lock, particularly in forced entry situations.
Key Benefits and Security Considerations
One of the primary benefits of nightlatches is their convenience. Without the need to manually lock the door, they provide instant security once the door shuts. They’re also perfect for internal doors where access control is required — e.g., offices or flats.
However, the level of security they provide varies based on the type and quality of the lock. Basic nightlatches can be vulnerable to forced entry or lock-snapping, especially if poorly installed. That’s why locksmiths usually recommend upgrading to a British Standard nightlatch locks with a reinforced strike plate, anti-drill features and a deadlocking option.
Security can also be breached if the lock is outdated or the door frame is not sturdy. In most instances, burglaries occur not through the lock but via weak or improperly maintained door frames. A professional locksmith will inspect both the lock and frame to suggest the optimum method of securing the entry in a proper manner.
When to Call a Locksmith
There are a few reasons why you may require the services of a locksmith for a nightlatch. The most common are lost keys, worn mechanisms, or a lockout. Locksmiths may also replace an existing lock, fit a new lock for improved security, or replace malfunctioning latches that don’t work as smoothly as they once did.
If you’re taking up residence in a new building, it is advisable to change or rekey the nightlatch to ensure that it is not accessed by unauthorised people. For aged locks or those which are loose, sticky, or out of place, professional maintenance can usually repair the lock before it is a security issue.
Selecting the correct type of nightlatch — and having it professionally fitted — is as important as the lock itself. A professional locksmith will be able to suggest a model that suits your door, is insurance-approved, and fits how you live or work.
