King Locksmith and Doors installs, repairs, and services concealed electromagnetic shear locks for businesses, government sites, and healthcare facilities across the DMV. Get a clean look, strong holding force, and code-ready egress.
Concealed in the frame header
ANSI/BHMA A156.23 · UL 294 · NFPA 101
Maryland, DC & Northern Virginia
A shear lock is an electromagnetic lock hidden inside the door frame. The magnet sits in the header, and a steel armature sits in the top of the door. When the door closes and power flows, the armature locks into the magnet and resists sliding, not just pulling. Nothing shows on the face of the door. That makes shear locks a smart fit for lobbies, glass storefronts, double-acting doors, and behavioral health areas. Most models release when power drops, so people can always exit safely.
The lock sits inside the frame and door, so it keeps clean lines and resists tampering.
Shear action holds against both pulling and prying, giving high security without any bulky surface brackets.
Fail-safe design unlocks on power loss or fire alarm, helping doors meet life safety code rules.
King Locksmith And Doors Inc. is a commercial locksmith and door company serving Maryland, Washington DC, and Northern Virginia. Our technicians install, align, and repair shear locks on hollow metal, aluminum, and wood doors. We work with small businesses, government agencies, hospitals, hotels, and enterprises. We also tie shear locks into access control, fire alarms, and request-to-exit devices. Every job is planned around your code needs, your schedule, and your budget, with clear pricing upfront.
A shear lock only works well when it matches the door, the traffic, and the codes in your building. Use these five quick checks to pick the right model before you order or install it.
ANSI/BHMA A156.23 grades electromagnetic locks by holding force. Grade 1 holds 1,500 pounds, Grade 2 holds 1,000 pounds, and Grade 3 holds 500 pounds. Many shear locks reach Grade 1 or beyond.
For a main entry, server room, or pharmacy, choose Grade 1. Interior office doors with low risk can use a lighter grade. Extra holding force adds little if the frame itself is weak. Ask us to review your door’s use before you decide.
Shear locks need a tight, steady gap between the header and the top of the door. They mount well in hollow metal frames and many aluminum storefront headers. Wood doors need a solid top rail for the armature.
Doors that sag, drag, or bounce will not lock every time. We check hinges, closers, and the frame first, then fix any movement before we install the lock. This step saves you from costly service calls later.
A bond sensor confirms the armature is fully locked to the magnet. A door position switch shows whether the door is open or closed. Together, they give your security desk a clear, real-time picture.
Many shear locks also offer a relock delay. This short pause lets the door settle and line up before the magnet engages, which cuts down on false alarms and failed locks. Ask for these features by name when you compare models.
A shear lock has no lever that releases it, so codes treat it as an electrically locked egress door. Most setups need a motion sensor, a push-to-exit button, and release on power loss.
The lock must also release when the fire alarm or sprinkler system activates. Maryland, DC, and Virginia each adopt their own code editions, and local fire marshals may add rules. We design every shear lock install to meet code and pass inspection.
Shear locks run on 12 or 24 volts DC and draw steady current while locked. A dedicated power supply keeps voltage steady and protects the magnet. Battery backup is an option only where your code allows it.
Shear locks connect easily to card readers, keypads, and building access systems. Since the armature needs no power, there are no wires to run through the door itself. That makes most upgrades faster, cleaner, and often less costly.
Both lock types use magnets and power, but they mount and perform in different ways. This side-by-side view shows where a concealed shear lock pulls ahead of a surface maglock.
Consideration
Shear Lock
Surface-Mounted Magnetic Lock
Fully hidden inside the frame and door
Bulky box and bracket stay visible
No exposed parts to pry or cut
Exposed housing can be pried or struck
Clean frame suits behavioral health spaces
Projecting housing can create ligature points
Keeps full height in the opening
Housing can lower clearance in the opening
Works on doors that swing both ways
Generally limited to single-swing doors
Most shear lock problems start with alignment, power, or wiring, not the magnet itself. Watch for these warning signs, and call a technician before an issue leaves a door unsecured.
We mount the magnet and armature, align the door, and wire the lock to your existing systems.
We fix sagging doors, loose armatures, and worn hinges so the lock engages reliably on every close.
We replace bulky surface maglocks with concealed shear locks for a cleaner look and better tamper resistance.
We connect shear locks to card readers, keypads, and access software, then test every door before handoff.
We wire fire alarm release, motion sensors, and exit buttons so doors meet code and pass inspection.
We test and replace power supplies, relays, and wiring to keep voltage steady and locks holding strong.
Tell us about your doors, and our team will recommend, install, and support the right shear lock for your facility.
