So, what separates a $30 deadbolt from a $200 high-security cylinder? It comes down to three pillars of protection: physical strength, mechanical complexity, and key control.
Physical Strength: Resisting Brute Force
Most burglars are opportunists, not master thieves. They’re more likely to use force than finesse. This is where industry ratings come into play.
- ANSI/BHMA Grades: The American National Standards Institute assigns locks a grade from 1 to 3 based on their durability, strength, and life cycle. Grade 1 is the highest commercial rating, meaning it can withstand a significant amount of force (like multiple hammer strikes) and has been tested for hundreds of thousands of cycles. While a Grade 1 deadbolt is a great start, it doesn’t automatically make it “high-security.”
- UL 437 Rating: This is the gold standard for security testing from Underwriters Laboratories. A lock with a UL 437 rating has survived an exhaustive battery of expert attacks, including picking, drilling, prying, bumping, and impressioning for over five minutes. It’s like a car’s five-star safety rating—a third-party verification of its protective capabilities.
High-security locks achieve this strength with features like hardened steel inserts that shatter drill bits and reinforced construction that resists prying and impact.
Mechanical Complexity: Outsmarting Skilled Attacks
While lock picking isn’t the most common burglary method, the vulnerabilities that allow for picking also allow for faster, simpler techniques like “bumping.” Lock bumping uses a specially cut “bump key” to jolt the pins into alignment for a brief moment, allowing the lock to open.
High-security locks combat these threats with layers of internal complexity:
- Security Pins: Standard pins are flat on top. Security pins come in shapes like spools (thinner in the middle) or serrated (grooved). When a picking tool pushes on them, they get snagged inside the cylinder, giving the illusion that the lock is picked—a “false set” that traps the tool and prevents opening.
- Sidebars and Secondary Locking Mechanisms: Some high-security locks, like those from Medeco or Mul-T-Lock, have a completely separate locking mechanism. In addition to lifting the pins to the right height, the key must also rotate them or engage a “sidebar” that runs the length of the cylinder. This is like having to solve two different puzzles at once.
Key Control: The Most Overlooked Feature
This is arguably the most important feature for a homeowner. Key control is the regulation of who can make a copy of your key. Standard keys can be duplicated at any hardware store or kiosk in minutes, meaning every key you hand out is a potential security risk.
High-security locks solve this in two ways:
- Restricted Keys: These are keys with a unique keyway design that is not available in public retail. Duplicates can only be made by authorized locksmiths after verifying your identity against a signature card.
- Patented Keys: This is the highest level of key control. The key design itself is legally protected by a utility patent. This makes it illegal for anyone other than the original manufacturer to produce the key blanks. When you want a copy, you must go through a strict, documented procedure with an authorized dealer.
For anyone who has service providers, tenants, or family members needing access, patented key control ensures you know exactly how many keys to your home exist and who has them. If a key is lost, you don’t have to worry about it being duplicated; you simply need to consider a lock rekeying service to reset the lock to a new key.
