Publish Time: 2025-09-22 Origin: Site
In diverse architectural and access control scenarios, selecting the appropriate mortise lock is critical to ensuring security and functional efficiency. Known for their mechanical strength, durability, and versatile configurations, mortise locks have become the preferred solution for applications ranging from residential to commercial and industrial facilities. With varied functional types available, identifying the optimal lock for specific applications is very important. This article provides an analysis of mortise lock types, along with selection guidelines and terminology reference.
Mortise sash lock
The sashlock features both a latch and a deadbolt. The latch is operated by the handle (from both inside and outside), while the deadbolt is operated by a key or thumbturn. It is one of the most versatile and secure options, suitable for both residential and commercial buildings.
Mortise escape lock
Designed for rapid evacuation during emergencies, this lock allows immediate exit from the inside without a key, even when the door is locked. It is critical for fire safety and other urgent scenarios. A simple press of the handle simultaneously retracts both the latch and deadbolt, enabling instant door opening and safe egress.
Mortise latch lock
This lock consists only of a latch, operated by the handle to open and close the door. As it has no anti-theft functionality, it is best suited for high-traffic interior passage doors where doors need to remain closed but not necessarily locked, balancing convenience and basic security.
Mortise dead lock
Designed without a latch, this lock relies solely on a deadbolt mechanism, which is operated by a key or thumbturn from either side of the door. It is ideal for infrequently used doors such as storage rooms or utility access doors, where high security is required with minimal daily traffic.
Mortise night latch lock
Equipped with an automatic locking function, the latch of this lock engages immediately when the door is closed. The lock can be opened from the inside by turning the handle, while external access requires a key. It is commonly used in spaces such as inner rooms, equipment rooms and other places with controllable risks.
Mortise night latch lock
This is another model of mortise night latch, featuring a latch and a snib. When the door closes, the snib is first depressed by the strike plate, automatically locking the latch. External access requires a key for operation. This design effectively prevents card slipping, resists prying, and enhances security. It is ideal for spaces requiring privacy and limited disturbance, such as operating rooms.
Mortise roller lock
When unlocked, the roller mechanism simplifies door operation by allowing smooth push/pull action without handle operation. This design supports bidirectional door movement and is often used in commercial settings such as high-end hotels or entertainment venues.
Mortise bathroom lock
This lock incorporates an indicator to show whether the bathroom is occupied. The latch is operated by the handle (from both sides), while the deadbolt can be retracted internally via a thumbturn. External emergency release is possible using a coin or screwdriver on the indicator’s release slot. It ensures both privacy and safety.
Mortise classroom lock
Combining the functions of a passage lock and a night latch, this lock serves as a night latch when locked (requiring authorized entry from the outside) and as a passage lock when unlocked. It is commomly used in educational settings such as classrooms.
Mortise mute lock
Functionally similar to a sash lock, the mute lock includes a POM material on the latch to significantly reduce noise during operation. It is ideal for environments requiring quietness, such as hospital wards, dormitories, and offices.
Mortise mute lock
This is another model of silent lock, featuring a specialized claw-latch mechanism designed to significantly reduce noise during door closing operations.
Mortise sliding door lock
This lock uses a hookbolt operated by a cylinder and is specifically designed for sliding doors.
To learn about DIROCK mortise locks, click here.
Terminology
Lockcase
The protective outer shell of a mortise lock, engineered to house the internal working components.
Latch
A self-engaging fastener which keeps the door leaf in a closed position and which can be released.
Deadbolt
A movable part of a lock that usually engages a locking plate and withdraws into a lock case that is operated at least in one direction by a key, handle or thumb turn.
Follower
A part of a lock that operates latch bolt and/or deadbolt(s) when turned by a spindle.
Forend
Part of a case through which the lock is fixed to the door leaf and through which the latch and/or deadbolt pass.
Strike plate
A component, fixed to a frame to engage a bolt, or bolts.
Center distance
Refers to the distance from the centre of the lock follower to the centre of the lock cylinder perforation.
Backset
Refers to the distance from the front edge of the forend to the vertical axis position of the lock follower and hole for cylinder.
Latch projection & Deadbolt projection
Refers to the height of the latch or deadbolt above the forend when locked.
Engage
It’s an action whereby a movable component (latch or deadbolt) successfully extends into and is secured by a corresponding fixed receiving component strike plate, thereby achieving a locked or closed state.
How to select the right mortise lock?
1. Usage Scenarios
Mortise locks are typically categorized into different grades (e.g., Grade 1, Grade 2, Grade 3) based on their intended use. Selection should account for whether the lock will be installed in residential or commercial buildings. For example, high-traffic commercial environments generally require higher-grade locks with enhanced durability and security.
2. Function
It is essential to clarify the desired functionality you want the lock to perform. Mortise locks may feature different bolt types, such as latch and deadbolt. For instance, latch-only mechanisms allow smooth operation, making them suitable for frequently used doors. Therefore, choose a lock whose functions align with your specific operational needs.
3. Security Requirements
Consider whether the lock will be installed on an exterior or interior door, as security needs vary by location. Evaluate factors such as door placement to determine whether advanced security features—such as deadlocking—are necessary.
4. Door Compatibility
Ensure the selected lock is compatible with the door’s type, material, and thickness.
5. Budget Considerations
Balance cost with quality. While high-quality mortise locks may involve a higher initial investment, they offer superior security and durability, delivering greater long-term value. When selecting a lock, consider its long-term benefits, not just the initial cost.
Common questions about mortise lock
Q1: Are mortise locks more secure ?
Yes, mortise locks are generally far more secure than other locks (such as cylindrical locks). Their strength comes from: a reinforced lock case embedded deep within the door, providing resistance against kick-ins, physical impacts; compatibility with high-security cylinders; and mortise locks offer multiple locking functions, (e.g., entry, office), allowing for customized security management. They are the preferred solution for commercial and residential applications.
Q2: How does a mortise lock work ?
A mortise lock works by embedding a locking mechanism into a pocket (lockcase) cut into the door, where a latch or deadbolt is extended or retracted to secure or release the door. Depressing the lever handle can retract the latch for entry. When locked, the key or thumb turn engages the deadbolt, extending it into the strike plate mounted on the door frame, providing resistance against forced entry.
Q3: Are all mortise locks the same size ?
No, there is no universal “standard size” for mortise locks. Dimensions—such as center distance, backset, lock case length, height, thickness—can vary significantly based on regional specifications and standards. For compatibility, always verify the door’s thickness and existing mortise dimensions before installation.
Q4: How to reverse a mortise lock ?
Handing reversal procedures vary by manufacturer. While some locks require disassembly the lockcase to rotate the latch, our DIROCK mortise locks can be reversed without disassembly. Simply use the provided reversing tool or a screwdriver to change the latch direction for right-handed or left-handed doors. We even offer a model that allows for tool-free reversal. For safe and correct handling, always refer to the manufacturer’s product-specific guidelines.
Q5: How to install mortise lock?
Mortise lock installation is a precision process that requires specialized tools and knowledge to ensure proper function and security. We recommend that it be installed by qualified personnel in strict accordance with the manufacturer's installation instructions. If you are undertaking a project, our sales team can provide guidance on product selection, installation recommendations, and more.
Conclusion
A review of mortise lock types and features, combined with key selection criteria, provides you with a practical framework to match specific needs with optimal solutions, ensuring functionality and security across diverse applications. For a tailored solution for your project, contact the DIROCK team for professional consultation.