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What is a Euro Mortise Lock

A Euro mortise lock is a recessed locking mechanism installed into a mortise cut in the door edge, designed to meet European standards. It is commonly used with Euro profile cylinders and lever handles, making it suitable for residential, commercial, and fire-rated doors.

Euro mortise locks are tested to EN standards such as EN 12209 for mechanical performance, EN 1634 for fire resistance, and EN 1670 for corrosion resistance. Compared to surface-mounted or cylindrical locks, they provide higher security, better durability, and smoother operation, making them a preferred choice for hotels, offices, hospitals, and other high-traffic buildings.

What is a American Mortise Lock

An American mortise lock is a heavy-duty recessed lockset designed to meet U.S. building and fire safety standards, commonly used in commercial and institutional buildings. It is installed into a mortise cut in the door edge and typically operates with lever handles and standard U.S. cylinders.

American mortise locks are often UL Listed and tested to UL 10C for fire-rated door assemblies, with mechanical performance aligned to ANSI/BHMA standards. Compared to light-duty cylindrical locks, they offer higher security, greater durability, and better performance under heavy traffic, making them ideal for offices, hospitals, hotels, schools, and other high-use commercial doors.

Explore Our Mortise Lock Variants

American Mortise Lock

Euro Mortise Lock

DDAL01	Passage Lock	A Passage or Closet Latch is a non-locking door function where the latch bolt is always operated by a lever from either or both sides, allowing free access. It is commonly used for closets, corridors, and interior doors.
DDAL04	Entry Lock	An Entry Lock features a latch bolt operated by levers from both sides, except when the outside lever is made inoperative by a stop or mechanical device. When locked, the latch retracts by key outside or inside lever, with an auxiliary dead latch.
DDAL05	Classroom Lock	A Classroom Lock allows the latch bolt to be operated by levers from both sides, except when the outside lever is locked by key from outside. When locked, the latch retracts by key or outside lever from outside, or by inside lever, with an auxiliary dead latch.
DDAL07	Storeroom Lock	A Storeroom or Closet Lock has a latch bolt operated by key from the outside or by the inside lever. The outside lever is always inoperative, preventing entry without a key, and includes an auxiliary dead latch for added security.
DDAL09	Public Toilet Lock	An apartment, exit, or public toilet lock allows the latch bolt to be operated by levers from both sides, except when the outside lever is locked by key from inside. When locked, the latch retracts by key outside or inside lever, with an auxiliary dead latch.
DDAL13	Exit Lock	A dormitory or exit lock allows the latch bolt to be operated by levers from both sides. The dead bolt is projected by key from outside and thumbturn from inside. Operating the inside lever retracts both bolts and unlocks the outside.
DDAL18	Dead Lock	A deadlock features a dead bolt operated by key from the outside only. It provides basic security without a latch function and is commonly used where controlled access is required and free passage operation is not needed.
DDAL19	Parivacy Lock	A privacy, bedroom, or bath lock allows the latch bolt to be operated by levers from both sides. The dead bolt is operated by a thumbturn inside and emergency release outside. Operating the inside lever retracts both bolts.
DDAL20	Apartment Lock	An apartment corridor door lock allows latch operation from both sides, except when the outside lever is made inoperative by a stop. The dead bolt is operated by key outside or thumbturn inside. Key operation retracts both bolts, while inside lever retracts both and keeps the outside locked.
DDAL22	Bedroom Lock	A privacy, bedroom, or bath lock allows the latch bolt to be operated by levers from both sides, except when the outside lever is locked by an inside thumbturn. Operating the inside lever, closing the door, or using the outside emergency release unlocks the outside lever.

DDML009	Sash Lock	A sash lock features a latch bolt operated by lever handles from either side. The deadbolt is thrown and retracted from one or both sides depending on the cylinder type. Cylinder operation controls both latchbolt and deadbolt, with a two-turn deadbolt.
DDML009-E	Emergency Escape lock	An emergency escape lock allows the inside lever handle or panic exit device to withdraw both latchbolt and deadbolt in one single action. It is designed for fire safety applications where immediate escape and high security are required.
DDML010	Roller Latch Mortise Lock	A roller latch mortise lock uses a roller bolt that automatically closes from either side. The deadbolt is thrown and retracted from one or both sides depending on cylinder type. Cylinder operation controls the deadbolt, with a two-turn throw.
DDML011	Latch Lock	A latch lock allows the latch bolt to be operated freely by lever handles from either side at all times. It provides simple passage functionality without locking and is suitable for interior doors where security or privacy is not required.
DDML012	Bathroom Lock	A bathroom lock allows the latch bolt to be operated by levers from either side. The deadbolt is operated by an inside thumbturn. An external indicator with emergency release can be fitted to operate in conjunction with the thumbturn.
DDML013	Deadbolt Lock	A deadbolt lock provides security using a deadbolt only, which is thrown and retracted from one or both sides depending on the cylinder type installed. The deadbolt features a two-turn operation for increased resistance to forced entry.
DDML014	Night Latch Lock	A night latch lock features a latch bolt operated by an inside lever or exit device and by key from outside. The door automatically relocks when closed. An auxiliary deadlocking latch provides anti-card protection, and the outside lever is dummy.
DDML015	Classroom Lock	A classroom lock allows the latch bolt to be retracted by levers from either side unless the outside lever is locked by key. The outside is unlocked by key, while the inside lever always allows free and immediate exit.
DDML021	Narrow Stile Lock	A narrow stile lock is designed for slim aluminum door profiles. It features a compact mortise case, smooth lever operation, and compatibility with Euro profile cylinders, providing reliable security and stable performance for commercial aluminum and glass door systems.
DDML027	Mortise X-Ray Lock	A mortise X-ray lock is designed to prevent X-ray penetration. The latch bolt is operated by lever handles from either side. The deadbolt is thrown and retracted by cylinders on both sides to ensure secure shielding performance.
DDML029-B	Deadlock Lock Body	A deadlock lock body features a deadbolt that is thrown and retracted from one or both sides depending on the type of indicator or cylinder installed. It provides secure locking without a latch function for controlled access applications.
DDML031	Sliding Door Hook Lock	A lock uses a hook-shaped bolt that engages securely into the door frame when locked. It prevents door lifting and forced sliding, offering improved security, smooth operation, and dependable performance for commercial and residential sliding door applications.
DDML044	Magnetic Mortise Lock	A magnetic mortise lock uses a magnetic latch bolt that automatically engages when the door closes. The latch is operated by lever handles from either side. Cylinder operation controls both magnetic latchbolt and deadbolt, featuring a two-turn deadbolt.

Designed for High-Security Environments

Commercial

Education

Government

Healthcare

Institution

Residential

Transportation

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Mortise Lock Anatomy

How D&D Hardware Mortise Locks Outperform

Is it certified for fire-rated and commercial use?

Yes—mortise locks can be CE-marked and UL-listed, ensuring full compliance with fire door and building code requirements.

How long will it last in daily use?

Proven durability with EN1935 /ANSI Grade 1 operating cycles for high-traffic commercial doors.

Can it support different door functions?

Multiple configurations—passage, privacy, classroom, office, and emergency exit—make mortise locks suitable for diverse project needs.

How secure is it against forced entry?

A full lock case and reinforced latchbolt design offer higher resistance to prying and impact than surface-mounted locks. The recessed internal structure distributes load inside the door, providing superior strength for steel, timber, and fire-rated doors.

Is installation complicated or project-friendly?

Designed as an industry-standard format, mortise locks integrate easily with commercial door preparation and hardware schedules.

Can it be customized for project requirements?

Backset, faceplate size, latch type, finish, and function options allow mortise locks to be tailored to project requirements.

Tested & Certified for Global Standards

CE Door Lock – Certified Performance

UL Door Lock – North American Compliance

Concise Installation Guide

Drill & Insert – Cut the mortise cavity using the template, then insert the lock case, ensuring the front plate moves freely.

Spindle & Spring – Insert the spindle and spring into the cam on the bolt side of the lock case.

Lever Assembly – Attach the spring shelf to the screw bolt on the lever back, keeping the toggle switch unlocked. Press the lever flush to the door.

Cover & Secure – Insert the spring shelf into the spindle, cover with the rose plate, and fix it with screws. Install the outer rose and adjust the lever tube using the provided wrench.

Cylinder Installation – Rotate the cylinder into the lock case. Compatible with a 6‑pin solid brass ANSI cylinder (master key available). Secure with screws.

Thumbturn & Plate – Insert the thumbturn through the door hole and fasten with screws. Finally, fix the front plate to the lock body.

Full Customization Options to Mortise Locks

Multiple Surface Finishes

D&D offers a wide selection of surface finishes to meet different architectural styles and environmental requirements. Finish options are designed to maintain durability, corrosion resistance, and visual consistency across both CE and UL compliant door hardware systems.

High-Quality Stainless Steel Material

All D&D door locks are manufactured exclusively from high-quality stainless steel. This material ensures excellent strength, corrosion resistance, and long-term durability, making it suitable for demanding commercial, institutional, and fire-rated applications in both CE and UL projects.

Flexible Key Management Systems

D&D supports multiple key management functions, allowing customers to choose from various keying systems to suit different security levels and access control requirements. Options are available for simple keying arrangements or more complex master key system configurations.

Multiple Lock Functions Available

A wide range of lock functions is available to support different application needs, including passage, privacy, office, storeroom, and other functional requirements. D&D door locks can be configured to match specific building usage and security control scenarios.

Multiple Euro Profile Sizes

For Euro standard applications, D&D offers multiple case sizes such as 5572, 5578, 6072, and additional configurations. This flexibility ensures compatibility with different door constructions, thicknesses, and regional specification requirements.

Looking for a specific mortise lock?

At D&D Hardware, we offer customization services to meet your unique door requirements.

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Why Mortise Locks Are Preferred in CE & UL Projects

Handle locks are often suitable for light-duty or residential applications, but they may fail to meet fire, durability, and compliance requirements in regulated projects.

CE- and UL-certified mortise locks are engineered specifically for commercial, fire-rated, and high-traffic doors, making them the safer and more reliable choice for B2B projects.

Criteria	Mortise Lock	Handle Lock (Lever Lockset)
Installation Method	Recessed into door edge	Surface / bored installation
Structural Strength	High – internal load distribution	Medium
Fire Door Certification	EN 1634 / UL 10C approved	Limited or not applicable
Durability Testing	EN 12209 – 200,000+ cycles	Typically lower
Security Performance	High anti-prying resistance	Moderate
Door Type Compatibility	Timber, steel, fire-rated doors	Mostly timber doors
Hardware Integration	Certified full door hardware set	Limited integration
Corrosion Resistance	EN 1670 Grade 4 available	Usually lower grade
Project Acceptance	Widely specified in projects	Often restricted
Lifecycle Cost	Lower long-term	Higher due to replacement

FAQs

1. How to choose the right mortise lock for a project?

Select a mortise lock based on door type, fire rating, usage frequency, required function, and certification standards (CE or UL) to ensure compliance and long-term reliability. Our mortise locks are tested to EN 1634 and UL 10C, making them suitable for certified fire-rated door assemblies in CE and UL projects.

2. Why do contractors prefer certified mortise locks?

Certified mortise locks reduce compliance risk, inspection issues, and long-term maintenance costs, making them the safest choice for commercial projects.

3. Why should we choose your mortise lock over other suppliers?

Because we offer CE & UL certified mortise locks, proven durability, consistent quality control, and reliable support for commercial and fire-rated door projects.

4. How to replace a mortise lock?

To replace a mortise lock, remove the lever handles, cylinder, and faceplate, then slide the lock body out of the door edge. Measure the backset, case size, and spindle position before installing a compatible replacement to ensure proper alignment.

5. Can a mortise lock be replaced without changing the door?

Yes, if the new mortise lock matches the existing case dimensions, backset, and handle centers, replacement can be completed without modifying the door preparation.

6. What measurements are required before replacing a mortise lock?

Key measurements include backset, lock case height and depth, spindle center distance, faceplate size, and cylinder type. These ensure compatibility with existing doors and hardware.

7. What causes mortise lock failure in projects?

Common causes include incorrect selection, non-certified locks on fire doors, poor installation, or insufficient corrosion resistance for the environment.

Best-Selling Mortise Locks

Deeper Reading

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What are the functions of the American standard Mortise Lock?

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