This process will vary somewhat based on the doorknob you are installing.
How to fit a internal door lock.
Open the door and stand with your back to the hinges.
Mark out the strike plate on the door frame after you ve fitted the lock in the door you need to fit the strike plate to the door frame.
Shake the door a bit to make sure it is secure.
Remove the two screws from the latch plate on the edge of the door and remove the latch from the opening.
This allows you to pull the door knobs off the door from both sides.
If you re installing a pre hung door make sure you get the correct swing determined by the placement of the hinges and doorknob.
Using a square mark this centre line for approximately 4 100mm on the face of the door the pencil mark can be removed later with an eraser or damp cloth.
Fit the wedge into the bottom of the door as close to the wall as possible.
Create a mortise for the plate around the latch on your door using the technique described above.
Purchase a door stop or professional grade door wedge from a local hardware store or from an online retailer.
Place a wedge at the bottom of the door to keep it in place.
In some cases door latch plate mortises might need to be cut or enlarged.
If the knob is to the right select a right handed door.
Tools needed for this job.
If the doorknob is on the left you need a left handed door.
Then use a drill to make the necessary holes for installation of your doorknob door handle and lock.
Hold the door latch against the face of the door flush with the door edge and mark the spindle centre on your previously marked centre line see fig 1.
Begin by removing the screws from the door knob on the interior side of your door.
Tape measure pencil flat drill bit for wo.
Create a mortise and holes for your lock and door handle.