

High security · Norfolk County
High Security Locks
You run a home office with client files and equipment, and your insurer has asked what kind of lock is on the door.
In plain words
Upgrading to high security rarely means new doors or a big disruption. Many high security cylinders retrofit into the existing deadbolt or lever, so the door preparation stays as it is and only the cylinder and keys change. A heavier deadbolt uses the same bore as the old one in most cases. The strike and hinge screws are swapped for long ones that bite into the framing. The visible difference afterwards is small; the practical difference is that the door resists the tools and tricks that defeat ordinary hardware, and that nobody can copy your key without you knowing.
How the visit goesThe restricted keys you bought years ago are no longer restricted; the locksmith mentioned the patent has run out and blanks are sold openly. Your key control quietly stopped being control.
High Security Locks
How the visit goes


Matching the rating to the risk
Ratings are only useful if someone explains them. A residential deadbolt carries a hardware grade for security, durability and finish based on hammer blows, pulling force and cycle testing. A high-security cylinder carries a separate laboratory listing based on how many minutes it resists picking, drilling and forcing. The locksmith explains what each figure means in practice for your door and points out the rule that matters most: the whole assembly takes the grade of its weakest part. That conversation ends with a recommendation you understand rather than a part number you have to trust.
Retiring the old keys and closing gaps
Part of the visit is making the old keys meaningless. Once the new cylinders are in, every previous key is tried to confirm it no longer operates anything, and any remaining door on the old keyway is either upgraded or at least rekeyed so an unknown copy has nowhere to go. The locksmith also closes small gaps found during the assessment: replacing hinge screws with long ones, adjusting a closer, adding a cylinder guard, or moving a thumb-turn away from glass. The door leaves the visit as one coherent assembly rather than one strong part among weak ones.
A key plan that survives staff changes
For a business, the handover includes a key schedule showing every cylinder, every key number and who holds it. When someone leaves, their key comes back and is struck off; if it does not come back, you know exactly which doors it opened and can decide whether one cylinder or several should be repinned. Because the keyway is restricted, a departed employee cannot quietly keep a copy. New hires are issued a numbered key against a signature. The plan lives in a folder or spreadsheet, and the locksmith keeps a matching record so the two can be reconciled whenever you like.
High Security Locks
In the van
Box strike
Wrap-around door reinforcer
Graded deadbolt with hardened bolt
Hardened cylinder guard ring
Three-inch strike and hinge screws

High Security Locks
What affects the quote
Documentation and registration
Setting up the key register, recording signatories and providing a written schedule of cylinders and keys is real work on a business system and is listed rather than hidden.
Distance and access
A rural property, a high-rise with loading dock rules or a site that must be visited outside trading hours affects travel and scheduling, and the quote says so plainly.
Cylinder rating and format
A patented residential cylinder, a laboratory-rated commercial cylinder and an interchangeable core sit at different points on the scale, and the format that fits your present hardware decides which lines are available.
What to have ready
- Would you like all doors on one key, or different keys for different areas?
- For a business, who should be allowed to authorise new keys?
- Has the door ever been forced, or has a key been lost or not returned?
High Security Locks: questions
QuestionsWhat actually makes a lock high security?
Three things working together. The cylinder has a second locking mechanism, usually a sidebar released by finger pins or rotating pins, plus hardened steel in the path of a drill, so picking, bumping and drilling take far longer than on an ordinary lock. The deadbolt and strike are heavier and fastened into the framing. And the key is cut on a patented or restricted blank that only an authorised person can have copied. Remove any one and the door is weaker than the label suggests.
What about the glass panel next to my front door?
A sidelight within reach of the inside thumb-turn is the weak point of an otherwise strong door, since a broken pane lets a hand reach the turn. Options include moving the deadbolt further from the glass, a lock function that needs a key inside as well, or a laminated pane. Because everyone must still be able to leave easily, the locksmith talks through the trade-offs and helps you pick the arrangement that suits your household.
Why does the locksmith care so much about the strike plate?
Because that is where a kicked door fails. The bolt is strong, but it sits in a pocket in the jamb held by a thin plate and short screws, and a boot splits the wood around it. A reinforced strike or box strike fastened with three-inch screws into the wall framing spreads the blow along the frame. It is the least visible part of the upgrade and often the one that does the most.
