How to Choose High-Security Door Locks

Residential front door with decorative electronic door lock

This article is part of our series, “Burglary Prevention Starts at your Door.”

With more than 50% of burglars entering homes through either the front or the back doors, it is no surprise that you should take every precaution to secure these entry points. In our previous post, we talked about how to choose burglar-resistant doors. However, strong doors without high-quality locks defeat the purpose. We will now explore how to choose the best residential door locks for your home.

Evaluate your Current Locks

Before you invest in new home door locks, take the time to assess the locks you currently have. It is possible that your locks are excellent and nothing needs to be done. Or, your current locks may be a good start, to which an additional lock can be added to strengthen the door’s security. So, have a trusted locksmith in your area come to your home and evaluate your existing locks.

Common Types of Home Door Locks

Doorknob Lock. These are doorknob and lock combinations. The interior knob has a decorative doorknob lockmechanism to set the lock, and the exterior knob has a keyhole. The lock mechanism is part of the knob and is not installed separately through another part of the door.  The doorknob control simply keeps the knob from turning and releasing the door latch.

This is the least expensive type of lock, but it is also the most vulnerable. Doorknob locks can be easily picked or broken off with a hammer. Therefore, knob locks should never be the only lock on an exterior door. They are much more suited to interior doors, where privacy is the main goal, not security.

Horizontal Deadbolt Lock. This is the most common type of exterior door lock found in homes. These locks are Decorative brass single deadbolt lockinstalled through the door. The key operates a metal bolt that slides into a hole in the doorframe to lock the door. There are single deadbolt locks and double deadbolt locks. Single deadbolt locks, as shown here, have a keyhole on the outside and a thumb turn on the inside. A key is only needed to operate the lock from the outside. Double deadbolts require the key on both sides.

Most homes have single deadbolt locks. Double deadbolt locks are considered dangerous for household use, because in an emergency, people can be trapped inside if the key is not nearby. While these horizontal deadbolt locks offer good security, a determined burglar can still pry the lock away from the doorframe.

Jimmy-proof deadbolt lock

Vertical Jimmy-Proof Deadbolt. Unlike the horizontal deadbolt, the bolt on a jimmy-proof lock does not slide horizontally into a hole in the door frame. Instead, the bolthousing is mounted on the inside of the door, and it slides vertically through holes in the strike plate attached to the inside of the door frame.

Because the lock is mounted completely inside, no one can pry the lock from outside. As a result, these locks offer a higher level of security than standard deadbolt locks, and can feature either single or double deadbolts.

Mortise Lock. These locks are less commonly used. However, because of Mortise locktheir design, they offer great security without taking away from the beauty of your door. Mortise locks have a metal housing that is inserted into a pocket, or mortise, in the door. The metal housing protects the lock mechanism and makes these locks very difficult to break.

Keyless Lock. Today, many deadbolt locks come with keyless entry. Instead of traditional keys, these locks use keypads, electronic thumbprint scanners, and even smartphones to operate the lock. Keyless locks offer great convenience and may be a good fit for you.

Other Security Features

There are additional security-strengthening features you should consider when choosing a lock. For example, make sure the bolt extends at least 1” into the door frame when locked, and still has a good piece left inside the door itself. The farther the bolt extends in each direction, the stronger the lock.

Also, consider reinforcing the strike plate (or striker), which is the metal piece mounted on the door frame around the hole that the bolt goes into. You can upgrade your current strike plate by changing to 3” screws, which make the strike plate less likely to give way under pressure. To further reinforce it, try replacing the existing strike plate with a longer one that covers more of the inner door frame and uses more screws. This will further strengthen your lock.