The best way to reinforce your frame is by adding a layer of steel to prevent them from splitting. This makes your door kick proof. Installation entails placing high-gauge steel over the door jamb and securing it with long screws. The screws should penetrate through to the wall studs on all sides of the doorway.
1) Put a Good Deadbolt Lock on the Door
Many of us will think about the locks on the front door as the first way of creating a secure, burglar-proof boundary between the home and any intruder. It helps to have a secure deadbolt on the door. These bolts will prove to be a difficult obstacle for a potential burglar.
Make sure your doors have deadbolt locks and cylinder guards, which provide an extra layer of security. If you have a sliding door, use keyed locks to secure it. You should also reinforce your door frame with 3-inch screws so a burglar can't pry it away from the wall with a crowbar.
A box strike gives the lock a far stronger hold on the door, and the 2-inch screws anchor it to the door frame.
Still, having longer screws isn't a guarantee that no one will be able to kick in your door. It might just take a bit longer for it to come apart. “Those longer screws go into the stud that's behind a door jamb, so instead of splitting that initial wood, it's in a deeper sub wood, so it's grabbing more,” Whipple said.
A strike plate or "Strike" is a metal plate that is secured to the door jamb for the purpose of reinforcing the latch on the lockset or deadbolt. They come in many different shapes and sizes, for various applications.
#1 A Strike Plate Defined
It has a hole or holes to allow for the door's bolt(s). The doorjamb, or doorpost, is the vertical section of your doorframe that secures the door. Once the door is closed shut, the door's bolt extends into the strike plate hole(s) and keeps it locked tight.
Strike Plate
This is the plate the latch-tongue, or deadbolt-tongue will connect with. It should sit flush with the door jamb. Any passage or privacy set needs to have a strike plate for the door to latch. Additionally, deadbolts need a strike plate to properly lock.
A minimum of 10, 75-pound strikes are reported to be the equivalent of over 100 foot pounds, which is why the Grade 1 deadbolt locks have been tested. A really strong criminal would have to kick your door over 100 times in order for it to begin to degrade or show signs of weakness.
To strengthen the strike plate on the lock, replace the existing screws with 3” long screws to attach into the wall stud. To reinforce the door frame even more, remove the door facing and attach a steel building plate to the door casing and wall stud.
Generally speaking, deadbolts are sturdy locks that can withstand kick in and other forced entry attempts. However, a door with a deadbolt can still be kicked down if the door itself is not solid. So, to protect your door against kick in, you want to make sure both the lock and door are of high-quality grade.
Deadbolt door locks are the most secure type of key lock and are usually used on a home's exterior door. Available in single- and double-cylinder styles, deadbolts are rated according to their strength from Grade 1 to Grade 3. A Grade 1 is the highest grade and provides the most security.
A doorstop will definitely not prevent all entries but when used properly it can withstand substantial force. In most cases, a regular doorstop won't keep intruders out but it can slow them down and when combined with other security measures it provides a real barrier and keeps the door in place.