Great DIY solution for those wanting to do the same. Things to consider is this is just one of several areas that need to be reinforced so a breach can be slowed down.
All of this starts with a solid door frame assembly that covers the king / Jack studs. The door obviously needs to be stout while balancing energy efficiency.
Next is using grade 1 lock sets for both the door knob & deadbolt. That is fortified by a cover plate for both. Next is the door hinge, strike plate, door jamb, and 3-4” grade 5 or better screws that indicate sheer force specifications.
This product from Armour Concepts has been the cornerstone of every security install we’ve done:
One of the cheapest and easiest security accessories is this Door Guardian. Once installed it’s impossible to pick / bump a lock set. Keep in mind this obviously is intended while at home.
All of these solutions are to provide you time so you can react accordingly. This is known in the security industry as Force Protection which is one of the four rings of security.
The above solutions should always use a out-swinging security door. As it requires more than 200-500% more force to pull vs push given the same force applied to breach a door.
Force Protection should always be the first level of protection before alarm systems, cameras, etc.
