In this post, we put together a long list of door handle glossary and terminologies. Most of the terms will be accompanied with clear and useful diagrams that help reader to easily understand the concepts. It is very useful for ones who are seeking a short answer or a quick definition to the terms/phrases that they’ve never heard or are unsure of. 

• Lockset: is a complete set of door hardware that makes a door functional. The components that complete a lockset vary depending on the function of the door. Usually it includes at least a pair of handles (or knobs), a pair of rosettes, a lock body, a strike plate, a strike box, and required fitting hardware. By purchasing a lockset, customers should have everything they need for the installation, except for the required tools and equipment, like screwdriver, drill, chisel etc.

• Backset distance. Backset distance, probably one of the most important terms door handle glossary, is the horizontal distance from the door edge (where the front plate sits flush to) to the axis that the door handles or the door knobs turn around. Common backset distance includes 50mm, 60mm and 70mm. If you are replacing an old lockset with a new one, it’s important to check if the backset of the new lock (a tubular latch or a lock body) matches the old one. The old backset distance measures from the door edge to the centre of the bore hole.

• Spindle: is a metal rod (or a shaft) that goes through the hole of a tubular latch (or a lock body). The spindle connects the door handles (or door knobs) to the latch or the lock body. As the handle turns, the spindle spins around its axis and operates the spring mechanism, which in turn retract the latchbolt. 

• Tubular latch: As the name indicates, a tubular latch is a latch whose casing has the shape of a tube, i.e. long, roundish and hollow. A tubular latch is often seen in a passage lockset where after installation, the door would be able to latch to a door jab (but not locked). A tubular latch can also be purchased separately in order to replace a broken latch. For example, readers can find a tubular latch from Bunnings for only $7.95

• Latch bolt: Latch bolt, another important term in door handle glossary, is a component that comprises a lock body, a tubular latch, or a mortice lock. It is a spring actuated bolt that protrudes out of the faceplate. It keeps the door latch when it shuts. Latch bolt is sometimes called a latch tongue because it sticks out and draws back as users turn the handles (or the knobs). 

• Reversible Latch Bolt. Reversible latch bolt is a latch bolt whose bevelled face can be reversed to either inside or outside. Lock body with reversible latch bolt allows universal door configuration (left-handed or right-handed, in-swing or out-swing, handles below or above privacy knobs) (See video below)

• Double throw deadbolt. Double throw deadbolt is a deadbolt that can be extended twice but turning the key. This makes the deadbolt stays deeper into the door jamb hence improve the security of the door (see the video below). This is an added feature to a mortice lock body and is becoming the popular choice in the industry. All entrance mortice locks from luxterior.com.au come with this feature.

• Retractable latch bolt. Retractable latch bolt is a latch bolt that can withdraw by turning the key. This feature assists single-handed entry and is very convenient. Users turn the key to withdraw the deadbolt and keep turning the key to make the latch bolt retracted. There is no need to turn the handle, making it really convenient, in case the user’s other hand is busy.

• Faceplate. The faceplate of a tubular latch or mortice lock is the flat rectangular surface that sits flush to the door end. Faceplate is often fixed to the door using a pair of screws. It helps hide the lock body inside the door. Faceplate has a thickness (usually a few mm) and the door end will need to be chiselled out the same amount in order for it to be installed flush to the door surface. 
• Strike plate: A strike plate is a metal plate that usually comes with a lockset. It comes with a hole (or holes) and is affixed to the door jamb using a pair of screws. When the door is shut, the bolt (latch bolt or dead bolt) from the lock extends into the hole in the strike plate and keeps the door closed. The strike plate also prevents the door jamb from being damaged by the bolt and reinforces the security of the door. 
• Strike box: is a box (with an open face) that sits between the door jamb and the strike plate. Together with the strike plate, the strike box forms a pocket that holds the bolt when the door is closed. The strike box prevents the raw jamb material from being exposed and retains the overall aesthetic of the system.
• Rosette: The rosette is a metal plate that positions between a door handle (or knob) and the door. The rosette helps cover the bore hole and more importantly, contributes significantly to the look of the whole lockset. Rosettes mostly come in circular and square shapes and can have different sizes. Sometimes a rosette can be of rectangular shapes. Usually the rosette has the same finish as the door handle.

• Bore: The bore, in door handle glossary, is the hole that is drilled through a door that the spindle and other connecting screws go through. This hole is where the handle from one side of the door engages with its counterpart from the other side. The horizontal distance from the center of the bore hole to the door edge is called the backset distance. There is no one-size-fit-all bore hole. Users need to refer to the instruction for the correct diameter.  
• Passage (function). Passage is a function of  interior doors that are used where general access is required. These doors stay latched when shut but can’t be locked. To open the door, users need to turn the handle (or the knob) to retract the latch bolt. Passage doors are usually used in hallways, study rooms or laundry.
• Privacy (function). Privacy is a function of interior doors that are used where privacy is required. These doors latch, stay shut and can be locked from inside, although users can gain access from the outside with a special tool (i.e. a coin or a pin) in case of an emergency or an unexpected event. Privacy doors are commonly used for bedrooms, bathrooms, and toilets.
• Entrance (function). Entrance is a function of exterior doors that allow users to enter the house (i.e. the front doors, the back doors, or doors to the side of the house). Entrance doors required a key to unlock from the outside and usually can be locked from both sides. Some people use entrance locks for bedrooms with valuable assets for extra security.