Choosing a Security Deadbolt

Choosing a Security Deadbolt

There are hundreds of deadbolts to choose from when you are upgrading your front door lock in Toronto.  How can a simple home owner make the right choice?  Together we will look at the five top UL437 deadbolts from the locksmiths point of view.  You can follow the same process I followed when choosing a deadbolt to recommend for your front door.  It is also the brand of deadbolt I put on the front door of my home and office. 

There are no real restrictions on using the term “High Security” to describe a lock.  There are insecure locks on the market with bold writing stating the claim of “High Security Deadbolt”.  Don’t be fooled.  High security is a term used by Underwriters Laboratories (UL or ULC) to describe the requirements for Section 437 of the Underwriters Code.  This code is written for insurance companies to help define the risk associated with a specific product.  Only locks that have passed rigorous testing by Underwriters Laboratories can place UL437 on their products.

In Toronto we have a sophisticated burglar to contend with.  They are now using tools to successfully gain entry.  As burglars become more proficient at breaking and entering our recommendations change to prepare you for a possible attack.  We try to make it hard for the burglars to take what you value.

At the time of this writing I recommend installing a grade two deadbolt or better on all exterior doors in Toronto.  However, the Ontario Building Code Act, 1992 recommends the following:  Deadbolt Lock

(1)  Except as permitted in Article, doors described in Sentence shall be provided with a deadbolt lock with a cylinder having no fewer than 5 pins and a bolt throw not less than 25 mm, protected with a solid or hardened free-turning ring or bevelled cylinder housing.


In plain English that means the lock should have these
minimum features:

1. One inch (1″) throw on bolt
2. Bolt should be dead locking
3. Lock should have a free-spinning collar
4. The key should have a minimum of five (5) cuts

The deadbolts described by these requirements are no longer keeping burglars out of homes and offices in Toronto.  With the upgrade to a grade two lock you will often find these additional features:

5. Larger diameter bolt
6. Larger bolts holding the lock on the door (1/4″)
7. Reinforced strike plate with long (3″) screws

When your budget allows for a more robust lock I recommend a UL437 grade 1 deadbolt for your exterior doors.  These are the deadbolts we are discussing in this article.

There are three things to look for in a UL 437 deadbolt.  First is key control.  Insurance companies want to make sure that a burglar who has access to your keys can’t just go to the corner store and make a copy for two dollars.  Second is tamper resistant.  This often means drill resistance.  The idea is that someone with power tools will have a hard time to take the lock off the door.  The third is pick resistance.  This means more pins.

Any lock that has achieved the UL 437 rating deserves our respect.  It is not easy (or inexpensive) to receive a UL 437 rating for a deadbolt.

Schlage Primus

Toronto’s most popular lock is made by a company named Schlage.  A few years ago Schlage entered the High Security lock game with its Primus brand.  Primus uses a side bar to add pins to the lock.  A milling on the side of the key allows the side bar to unlock.  A Primus UL 437 cylinder in a Schlage grade one B660 is a powerful combination.


The Assa key also incorporates a milling for a side bar, adding pins.  Both the Assa and Primus sidebars are restricted to a specific locksmith in each territory.  This means that the side bar code does not change from lock to lock.


While Medeco cylinders incorporate a side bar locking element there is no side milling on the key.  Instead the sidebar is released when the pins are rotated to the correct position.


The original high security lock has changed little since it’s invention.  Using disks similar to the dials inside a safe lock, rotating the key is like dialing a ten number safe combination.


The unique telescopic pin design allows Mul-T-Lock to give us ten pins.  Mul-T-Lock was my final choice for security deadbolt because of the additional features it offers.  The 3-in-1 feature gives the user the ability to change the key that operates the lock without calling the locksmith.  The bolt used was originally designed by Abloy, then redesigned by Mul-T-Lock.  It uses ball bearings that extend into the frame when the bolt is extended – making the bolt thicker than the hole in the frame it just went through.

The final point in Mul-T-Lock’s favour was the idea that one key can operate all the cylinders it manufactures.  They make just about every type of cylinder you can imagine.  Your front door key can operate your padlock, your mailbox lock, your filing cabinet and just about every other lock you use in a day.


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