How to Replace an Exterior Door Knob & Lock

Use your screwdriver to take out the two screws from the front edge of the existing latch unit, from above and below the latch. Take out the two screws on the base of the door knob that's on the inside of the door. Remove all the parts. You will be left with holes through the face and front edge of the door, intersecting each other.

Measure from the front edge of the door to the middle of the hole in the face of the door. Use that measurement to buy the properly sized knob and lock unit.

Slide the latch assembly through front hole of the door, pushing it all the way in until the latch is set against the door. Make sure the angled side of the latch faces the front (exterior) side of the door.

Screw in the latch plate to the front edge of the door with the two screws that came with the unit, using the same screw holes that were left in the door by the previous unit.

Push the two doorknob stems, with the knobs attached, through the hole in the face of the door, making sure the knob with the keyhole is on the exterior side and the knob with the lock release button is on the interior side. The stems of the knobs will fit through the back end of the latch unit, which will be visible in the hole.

Insert and tighten the two long knob screws on the base of the interior knob. Test the function of the latch and the locking mechanism.