Issues with Electric Strikes in Access Control Systems
Electric strikes were developed as a way to electrify mechanical commercial door hardware. Electrified locks were not widely available and electrified strikes enabled the remote release of these locks by tying them into an access control system or building entry via security officer or administration assistants. This flexibility enables administrators to remotely grant or deny access to individuals, leading to their widespread adoption across commercial buildings, government facilities, and residential properties.
Electric strikes are still widely used today due to many factors including habit, price, and the relative ease of powering and controlling at the door frame.
However, electric strikes have several limitations, and with the evolution of alternative electrified solutions which address most of these limitations, better suited options are available. In this post we’ll explore these issues and help installers make more informed electrification solutions decisions.
Electric Strikes Issues
Door Frame Modification Limitations
Installation of an electric strike requires cutting into the door frame. This can compromise the frame’s fire rating. To manage this, specialized hardware and approvals are needed prior to an intended door frame modification. This adds time and complexity to the installation process and unfortunately, many installers don’t realize this. Command Access customer and industry professional of 27 years, Michael Werbowski of Harry’s Locksmith explains, “With the enhancement of fire door inspections, people are only now coming to find out that field cutting in electric strikes is often violating fire code. You can’t just put a strike wherever you want to.”
Furthermore, cutting into the frame making permanent alterations is particularly problematic if you're not the building owner. Tenants would need to obtain permission or refer to their lease agreement before making irreversible alterations to the frame, and even if permitted, would usually need to return the opening to its original state which usually means replacing the whole door and frame.
Alignment and Preload Issues
Electric strikes can suffer from alignment issues. Werbowski states, “Wall construction variables can create alignment issues with the door and frame, so when the door closes, it’s not plumb and square. You can only get so much adjustment with an electric strike. About 50% of the time, you’re going to have alignment issues over time with electric strikes, especially with Mortise Locks.” Because of the limited adjustment with electric strikes, any alignments issues prominent in retrofit application will affect reliable functionality.
Another common issue encountered with electric strikes is their inability to handle preload. Preload is caused by HVAC air pressure differential across the door. Preload creates pressure on the door latch creating a resistance that the electric strike may not mechanically be able to overcome, causing an intended release to fail. It’s common in such situations to mistake the hardware for being faulty, resulting in additional service calls which drains profits and resources.
Design and Aesthetic Issues
Beyond the practical concerns, electric strikes are clearly visible. Many business owners prioritize uniformity and consistency in the appearance of their premises and visible electric strikes may not be acceptable. Werbowski shares, “For our customers, aesthetics are important and electric strikes are not something we would recommend.”
The visibility of electric strikes may add security risk, especially if used on an exterior door. If not installed and adjusted correctly, it can create an opening point on the door frame, revealing the latching point of the lock. Latch guards can be helpful in mitigating the exposed point vulnerable to breach.
Electric strikes are also often noisy during both the release operation and when the door re-latches, which can be disruptive in workplace environments. Although electric strikes can be left unlocked electronically during business hours with the application of constant power to the strike’s solenoid, such practice may significantly shorten the life of the solenoid.
For electric strikes used with panic hardware there is no visual indication that the door is unlocked, so upon exiting, users will engage the push pad to open the door creating more noise and unnecessary cycles on the hardware. Also, it may pose a potential security risk by not being able to get visual confirmation on whether doors are locked or unlocked. Using them to electrically dog the door is therefore less than ideal.
Alternatives
Fortunately, several alternatives exist that can address these issues.
Electrification of the door hardware itself can provide electronic lock and unlock functionality. The early evolution of electrified locks and exit devices began with solenoid operation and can be utilized, however, many of the power and life cycle limitations above would persist. As technologies evolved, motorized electrification was introduced for electrified hardware and quickly became the best solution for motorized latch retraction and lever control. Motors provide solutions that are more energy efficient and extend the life cycle.
Motorized latch retraction and lever control is nearly silent in its operation and is integrated directly into the hardware. Devices equipped with latch retraction can be left in an electronically dogged position or lever control units in the powered state with almost no power required (see our post on the MLRK1 technology for further information). Latch retraction is available for exit devices including retrofit options. Mortise locks and cylindrical locks have motorized latch retraction and/or lever control solutions.
Although electric strikes are arguably simpler to install than electrified door hardware. Often, installers might not consider the need to replace the existing mechanical lock with the proper storeroom function mechanical lock to work with an electric strike. Installing electrified door hardware replaces the mechanical lock with the correct electrified function lock, a 2-1 deal! A power transfer hinge (which again brings power into the door invisibly) is used to supply power to the electrified door hardware.
Electrifying door hardware is a different or new approach for many than what is required for an electric strike. But after a few installations – Mike says he “Prefers coring a door & installing electrified hardware vs. cutting in an electric strike those suck!” However, the real payoff comes in the form of more problem-free operation reducing total cost of ownership, enhanced security, quieter operation, and improved aesthetics.
Next Steps
If you have been installing electric strikes, all hope is not lost. A door with an electric strike may be upgraded to a motorized locking solution with an electric strike filler plate used to cover up the frame exposed by the removal of the electric strike.
Before defaulting on a door electrification decision to an electric strike, evaluate and ensure your options meet code and performance requirements so your customer will know they made the right decision to call you!