Choosing the
right door lock for your door and one that will work with your door handle trim
can be a daunting task even for the seasoned design professional. It doesn’t
help that within the door hardware industry many terms like lock, latch, and
deadbolt are used interchangeably and often without a complete prefix to
identify their use. So I have tried here in what will be the first in a series
of posts, to provide definitions for commonly used terms.
Latch – this term is so generic it is of little help unless it is described more fully. So consider what you are using the latch for, is it going to simply hold the door in place when it meets the door jamb, is it in other words just a humble devise that closes the door? While this is a latch it will often be referred to as tubular latch. A tubular latch is most commonly used for interior doors that you do not need or want to lock, they work either with a door knob or a door lever and the act of turning or depressing the handle releases or extends the latch “ tongue” into the door “strike”.
Strike - This is the metal plate that covers the
cut out area in your door jamb that the tongue of the latch fits inside thereby
keeping the door closed. When you push down on the door lever the tongue is
retracted from the strike and the door opens.
Latch bolt/deadbolt –here the latch is doing more than
simply closing the door, with this latch we can “throw” the bolt part of the latch so that it keeps the
door fixed in the jamb, so the door is now locked. The bolt will be thrown by a
turn piece. This is a commonly used for bathrooms or powder rooms that you lock
from one side. However, if you do decide to go this route you should make sure
that you have a release hole and release key so that you can open the door from
the outside in the event of an emergency. The “key” here refers to a simple key
essentially a narrow shaft of metal that is inserted into the deadbolt through
the hole on the outside of the bathroom door.
Passageway versus Privacy latches - These are commonly used terms with
names that define their use. A passageway latch is simply a non-locking latch
as described above. The privacy latch also called a privacy tubular latch is
the same latch but a small pin can be pushed through the latch to keep the
tongue of the latch fixed in the jamb, now the door is locked. The same pin can
be used to release the latch, allowing the door to open. Most privacy latches
are designed so that the pin that locks the door can be released by the turning
the knob or depressing the lever on the inside of the door.
In the next
piece in this series we will be reviewing how keyed cylinders are used with
deadbolts and how they are used.
