For additional security some people will recommend or install a chain guard or a sliding bar lock and this is for a few reasons – they’re cheap, easy to install and allow for communication with your visitor. Don’t fall victim to this logic.
- They’re easily bypassed. If the intruder can disable your primary lock or kick the door in enough to make the primary lock ineffective these little lock guards aren’t stopping them either.
- They are definitely easy to install. Why? Because they use 3/4” screws to attach to the door and door frame. The small screws do not provide much resistance when force is applied to the door. In addition, the screws are attached in the same direction the force would be applied to the door, providing virtually no resistance
- Easy to communicate with visitors is the best reason to not have one of these. Once you’ve cracked your door to a potential intruder, you’ve now removed all barriers between you and the intruder and making it easier for them to shoot, stab or get even better leverage to apply force and pop the sliding bar lock off the door.
What you should use instead is a one-sided deadbolt and a peephole camera.
The one-sided deadbolt is installed about 6” above your existing deadbolt and works just like it with the exception that it can only be locked from the inside and nothing visible on the outside.
It should be installed with at least 3” long screws and a strike reinforcement plate. The 3” or longer screws will be long enough to catch the studs framing the door opening and will make it much harder to come loose with brute force alone. A typical strike plate only has room for 2 screws. A strike reinforcement plate is a metal plate that acts as the strike plate but has 2 or more additional screw holes which allows for additional attachments to the studs.
A peephole camera works just like a typical peephole but has a camera with a screen large enough to be seen several feet away. This prevents you having to get right up to the door to look through the small eyepiece and keeping you safely away from the door in the event they want to attack when they think you’re close.