Glossary of Terms
A GUIDE TO LOCKS AND LATCHES
RIM LOCK OR LATCH:
This refers to locks or latches which are fitted on to the face of a door, opposed to a mortice lock or latch which is fitted into a recess cut into the door.
A set of rim lock furniture usually consists of a pair of rim knobs, a spindle, a rim lock and an escutcheon (key hole cover) for the outside face of the door.
A set of rim latch furniture is the same apart from the fact that an escutcheon wouldn't be required as there would not be a key hole.
This is an alternative way of securing a door closed instead of a latch. A roller bolt can be operated by a simple pull handle.
This is a circular plate on which the handle or knob are mounted.
A concealed rose simply means that the screws and holes used to fix the rose to the door are hidden by a cover.
A mortice lock containing both a latch (operated by door handles) and a bolt (operated by a key).
This is a small button or switch on the case of a nightlatch which can be used to lock the latch tongue in an open or closed position.
This is a square bar inserted through the latch case which connects the handles and enables the latch tongue to be operated.
This is a plate fixed to the door frame with one or more holes, into which the latch tongue or bolt engages.
The turn used to operate a bolt or privacy lock where a key is not required.
This is a much smaller piece of equipment than say a box latch. It requires a much smaller recess to be cut into the door and is therefore much quicker and easier to fit.
TURN AND RELEASE:
Used with a bathroom lock for privacy purposes, usually on bedroom or bathroom doors.
By operating the thumb turn the door can be locked from the inside without the need for a key. They can also be operated from the outside with a coin or screwdriver for emergency opening.
Generally it is possible to use your existing locks or latches, together with your new handles. However please ensure to check the following:
SASH LOCKS & BATHROOM LOCKS
The SASH LOCK comprises of a latch tongue, to be operated by the handle and a bolt to be operated by a key.
These lock have internal levers which are operated when the key is turned.
For internal doors a three lever sash lock is usually sufficient.
For external doors you should select a five lever British standard sash lock. Basically the more levers required to operate the lock the more secure the lock is.
BS3621 is the British standard covering lock security. The standard is strongly recommended by the police and insisted upon by most insurance companies.
The standard ensures that the lock is resistant to attack by drill, saw or force.
The BATHROOM LOCK comprises of a latch tongue, to be operated by the handle and a bolt that is operated by a thumb turn and release rather than a key.
There are two types of latches available:
TUBULAR LATCHES & BOX LATCHES
The TUBULAR LATCH is by far the most popular, due to its size and shape it is very quick and easy to fit.
The BOX LATCH serves the same purpose, however as a much larger recess is required to be cut into the door, it is not quite as easy to fit. The choice is often determined by the existing latch that you wish to replace.