Jim Lawrence Knowledge Base header

Locks & Latches Explained

What is a mortice?

This is the term given to a lock or latch that sits inside the door. It is named after a mortice and tenon joint that carpenters use to fix two pieces of wood together and is easily recognised as a door handle with nothing but a keyhole on the plate.
Behind the keyhole is the bolt (the tenon) that projects into the pocket (the mortice) that has been cut into the frame to secure the door to the frame.

What is a deadlock?

Generally, there are two types of mortice locks – deadlocks and sash locks. A deadlock is primarily designed to work on entrance doors of buildings. They have a single bolt locking system that is sprung so it will automatically lock behind you (like hotel bedroom doors) and can only be opened with the key.
Mortice lock
Sash lock

What is a sash lock?

This is a the most common type of door handle found in homes where there a latch set working in conjunction with the handle and locking mechanism so that the door doesn’t automatically lock behind you. They can be locked with a key when required.
Night latch

What is a night latch?

These are known as secondary locks or Yale locks, after one of the main manufacturers and should only be used as an additional form of security, not the sole lock on a door.
Escutcheon plate

What is an escutcheon?

This is a metal plate, often with a flap attached, that surrounds a keyhole for protection and ornamentation where it is separate from the door handle plate.
Rim lock

What is a rim lock?

This is a lock that is fitted onto the door rather than in it, usually housed in a surface mounted box with a handle and latch. Rim locks have been around since Medieval times and became incredibly decorative during the Renaissance.

They are not as secure as mortice locks and are not recommended on external doors as they can be easily removed, but they are ideal if your door is not thick enough to fit an internal locking system or used on internal doors or outbuildings where security is less important.  They are also a great way to add some period detail to your home.

At Jim Lawrence, we make a beautiful Victorian inspired brass rim lock in our Antiqued or Polished Brass and with a choice of two handle styles – our Holkham Knob or dropped Mews Handle.

Kindly note; before you order, you will need to determine whether you need a right or left handed side rim lock. To find out how, please read our guide.
Locking systems header

What is multi-point locking system?

These are the locking systems that are mainly found on UPVC doors but are becoming increasingly common on all types of external door. These locks have a number of locking points that lock simultaneously with the turn of a key. They generally come in two types:

5-lever locking system

This is the number of levers that the key has to move in order to allow the bolt to be thrown open or closed. When you insert the key into the lock and turn it, levers are pushed up. The more levers there are the better the security, so most insurance companies require a 5 lever lock to be used on external doors.

3-Lever locking system

Same as the 5-lever locks but with three so generally only acceptable to use on internal doors. The mortice locks we supply at Jim Lawrence are all 5-lever locks designed for lever handles, door knobs and privacy handles and are available in a choice of two finishes – Antiqued Brass or Steel.
Lock set
Bespoke handles header
Bespoke handle

Do you make bespoke door handles?

Yes, in many cases we can make a bespoke handle for you. If you require a non-standard handle to use with an un-sprung multi-point locking system (lift handle to lock, un-sprung handle) or a mortice lock (conventional lock with a sprung handle) we can make it to your specifications.

You can read our Guide for Bespoke Eurolock Handles here > where you can download a template that we will need to raise a quote for you.

Alternatively, you can call our friendly sales team on 01473 828989 for a template, fill in the required measurements along with which handle style you would like, its placement (left or right handed), the finish and type of edging you prefer and email us for a quote.