The basics of door hardware specifications

Secure the door

Understanding how to secure openings is an important step in the overall design and specification process.

Locking hardware

It is easy to get overwhelmed when discussing lock functions as sometimes as many as 50 functions could be listed in a product catalog. It is helpful to start with the following six basic functions that account for the vast majority of locks specified.

Passage set

Passage sets are used where doors do not need to lock. A latch bolt can be operated by a lever from either side at all times.

Privacy set

Privacy sets are used for spaces like restrooms or dressing rooms. They can be locked from the inside with a thumb turn or push button/turn for privacy, and they are typically unlocked from the outside using a tool rather than a key. There are several variations.

Storeroom lock

Storeroom locks are used when the outside lever should be locked at all times. A key is used to retract the latch bolt and open the door; when the key is removed the door is locked on the outside.

Low-energy automatic operators are used where a knowing act, such as a push button, is used to automatically open the door.

Entrance/office lock

These may be controlled by a key in the outside cylinder or by a thumb turn or push button/turn on the inside. The outside lever may be left in a locked or unlocked position.

Traditional classroom lock

Classroom locks are controlled by a key in the outside cylinder, which locks or unlocks the outside lever. The lock can be left in the locked or unlocked state by using the key, and there is no means of locking or unlocking the door from the inside. This function was originally designed for schools to prevent students from tampering with the lock, but most of the new institutions have classroom security locks, office function locks, storeroom locks, or electrified locks.

Classroom security lock

Classroom security locks allow control of the outside lever via key cylinders on both the inside and outside of the door. This allows a teacher to lock the classroom door during a lockdown without opening the door and possibly being exposed to an intruder in the corridor.

Mechanical locks

Tubular, cylindrical, mortise, deadbolt, and interconnected types of mechanical locks.


Tubular locks have a center spindle assembly extending through the center of the lock body and latch, allowing for retraction of the latch when the lever or knob is rotated. While this type of lock is very common on interior doors and in residential applications, they are considered the least secure lock type.


Cylindrical locks are sturdier and considered more secure than tubular locks. The latch bolt assembly interlocks with one side of the lock chassis, making it easier to install, replace, and rekey. Cylindrical locks are also available in different formats that provide various levels of security, all of which use the same type of key.


Mortise locks are stronger and heavier than cylindrical locks, making them ideal for use in hospitals and schools. They require a pocket—the mortise—to be cut into the door where the lock is fitted. Mortise locks also provide a wide variety of choices for function, trim, key systems, and finishes.

Control the content you see on! Learn More.
Leave a Comment


Your email address will not be published. Required fields are marked *