- Deadbolt
A deadbolt is a heavy-duty mechanical or electromechanical device used to secure a door in the locked position. It should not be confused with a deadlatch; a deadbolt must be manually operated (via a key or thumb-turn) to extend or retract the bolt, whereas a deadlatch features a spring-loaded mechanism that automatically locks the door when it closes.
A deadbolt typically consists of a cylinder, bolt, strike plate, and a thumb-turn (for single-cylinder models) or a second cylinder (for double-cylinder models).
Key Components:
- Cylinder (Core): The part where the key is inserted. It houses the pins and springs that must align to allow the lock to turn.
- Bolt: The solid metal bar (usually steel) that extends from the door into the frame. It is the "dead" component because it cannot be retracted by pressure or "shimming" with a credit card.
- Strike Plate: The metal plate attached to the door frame. It reinforces the wood and provides a secure hole for the bolt to enter.
- Thumb-turn: The lever on the inside of a single-cylinder deadbolt that allows you to lock and unlock the door without a key.
- Faceplate: The metal plate on the edge of the door through which the bolt extends.
Deadbolts are available in two forms;
Type Outside Operation Inside Operation Description/ Use Case Single Cylinder Key required Thumb-turn (Snib) Standard for residential safety. Allows for a quick exit during a fire without searching for a key. Double Cylinder Key required Key required Higher security. Often used on doors with glass panels so an intruder can't break the glass and reach in to turn a knob. Related Standards
- Australian Standard AS 4145 - Locksets and hardware for doors and windows Mechanical locksets for doors and windows in buildings