Begin by removing the screws from the door knob on the interior side of your door.
How to fit a internal door lock.
If the knob is to the right select a right handed door.
Open the door and stand with your back to the hinges.
Place a wedge at the bottom of the door to keep it in place.
If the doorknob is on the left you need a left handed door.
If you re installing a pre hung door make sure you get the correct swing determined by the placement of the hinges and doorknob.
Tape measure pencil flat drill bit for wo.
Turn the key so the locking bolt protrudes from the lock and hold the door against the door frame.
Purchase a door stop or professional grade door wedge from a local hardware store or from an online retailer.
Create a mortise for the plate around the latch on your door using the technique described above.
This video is about how to fit a door latch and door handle in an interior door.
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.
This allows you to pull the door knobs off the door from both sides.
First mark out the place where the strike plate has to be fitted.
In some cases door latch plate mortises might need to be cut or enlarged.
Create a mortise and holes for your lock and door handle.
Remove the two screws from the latch plate on the edge of the door and remove the latch from the opening.
This process will vary somewhat based on the doorknob you are installing.
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.
Fit the wedge into the bottom of the door as close to the wall as possible.