A proper functioning door lock is crucial to home security. Whether your lock is old, broken or just in need of an updated look, changing a door lock will take only minutes with the right size replacement and the proper tools.
Check the latch to know which door lock brand you have. This will ensure that no modifications will have to be made to the door and the door jamb.
Measured from the centre of the doorknob or bolt cover, to the latch edge of the door. Common lengths are either 2 3/8 inches or 2 3/4 inches. Many modern lock sets are adjustable for both measurements, however, double check before purchasing your new set.
Remove any visible screws from your old door lock using a screwdriver. Keep the door open after the screws are removed. Pull each half of the door knob straight out from the door. Use a butter knife or flathead screwdriver to loosen the latch in the strike plate, if the door closes on you.
Take out the old lock by removing the screws at the edge of the door. Compare the old screws to your new screws. If possible, reuse the old screws on the new lock, as changing the screws tends to weaken their hold in the door.
Check the hole on the door jamb, making sure it is deep enough and aligned to accept the new latch or bolt. Use a chisel to deepen the hole as needed.
Remove the old screws on the strike plate and replace with longer ones, i.e. 3 inches, for more security. The strike plate can be reused, except for if you want change it to a more stronger one.
Install the new lock mechanism. The installation is usually the reverse of removal. You can always read the manufacturer instruction sheet for more details.
Insert each half of the lock back together inside your door. Screw the lock screws tightly in the door.