Outside doors and frames should be made of solid wood or steel, which are harder to force open than hollow-core doors. Frames in outside doors should fit snugly (within 1/4 inch) against the door, and any glass around an outside door should be at least 40 inches or 1 meter from the lock or be unbreakable. To keep patio doors from being lifted off its track, limit clearance by installing screws or a plate that protrude down from the top track.

For added security you can also consider a floor mounted door stop. This is much more effective than a door chain, which is easily compromised with a good push.

Hinges should be attached securely by screws that go through the door frame into the supporting stud, and are not exposed on the outside. Replace outside hinges with non-removable hinges that are available commercially.

Locks

 Door security locks with key holes in the knob are unreliable, as they can easily be forced. Deadbolts should be used instead on all exterior doors, as the bolt can not be slipped with a card or tool, but can only be disengaged with a key. The minimum length of the throw should be 1" or 2.5cm, and the surrounding collar of the deadbolt should be made of good quality material or have a freely rotating slip ring so that it can not be crushed or twisted. A strike plate, which is the flat metal plate on the door frame that receives the lock’s throw or bolt, should be 6"-8" or preferably longer and installed with long screws that pass through the door frame and into the wall stud. Deadbolts provide good to excellent security depending on the quality.

Another type of bolt that can be used is the bolt rim lock, which has two vertically moving deadbolts that lock into a frame mounted striker above and below the door. These locks are suitable for wooden frames or where there are windows on the sides of the door preventing proper installation of a deadbolt. These locks provide good to excellent security, depending on the quality, and are more resistant to crowbars.

A system that is often found in older homes is the rim deadbolt lock. These are the simple sliding locks that are surface mounted on the interior of the door, and are easy to install but are poor security if simple screws are used. This type of lock should be updated with for better security.

Two more modern types of locks are the push button rim-locks and digitally coded deadbolts. A push button rim-lock features a keyless lock, opened by entering the correct combination on the numbered entry pad. This type of lock is popular in commercial applications but can be used in a residential setting as well. Keep in mind that the security code should be changed regularly so the number pad does not wear out from overuse. Digitally coded deadbolt systems with keypad or electronic remote are more expensive, but can be fitted to existing openings. They operate in the same manner as the traditional deadbolt system, but the locking mechanism can be activated without keys using an electronic remote. These systems can be of great benefit to seniors or people with disabilities.

To further add to the already increased security offered by a good quality deadbolt lock, the addition of a steel reinforcement device to both the door and frame greatly increases strength. Such a system is cost effective and simple to install. 

Outside doors and frames should be made of solid wood or steel, which are harder to force open than hollow-core doors. Frames in outside doors should fit snugly (within 1/4 inch) against the door, and any glass around an outside door should be at least 40 inches or 1 meter from the lock or be unbreakable. To keep patio doors from being lifted off its track, limit clearance by installing screws or a plate that protrude down from the top track.
For added security you can also consider a floor mounted door stop. This is much more effective than a door chain, which is easily compromised with a good push.

Hinges should be attached securely by screws that go through the door frame into the supporting stud, and are not exposed on the outside. Replace outside hinges with non-removable hinges that are available commercially.