Types of Door Locks

  • Passage set: No locking mechanism — for internal doors like hallways
  • Privacy set: Button or turn-lock on inside — for bathrooms and bedrooms
  • Entry set: Key-operated from outside, turn or button from inside — for external doors
  • Deadbolt: Separate bolt operated by key — adds security to an entry door

What You Need

  • New lockset (measure your existing backset — distance from door edge to centre of hole — usually 60mm or 70mm)
  • Phillips and flathead screwdrivers
  • Chisel and hammer (if enlarging the strike plate recess)
  • Optional: a hole saw if enlarging the bore hole

Step-by-Step Replacement

  1. 1

    Remove the existing handles

    Most handles have a small pinhole on the shank or a visible screw on the rose plate. For a pinhole: insert a pin or small screwdriver into the hole while pulling the handle off. For screws: unscrew the visible screws on the backplate/rose and pull the handles apart from both sides.

  2. 2

    Remove the latch bolt from the door edge

    On the door edge (the thin side of the door), you will see the latch bolt faceplate held by 2 screws. Remove these screws and pull the latch bolt assembly out through the door edge.

  3. 3

    Fit the new latch bolt

    Slide the new latch bolt into the door edge hole. Make sure the angled face of the latch points in the correct direction (toward the door frame when closed). Screw the faceplate in. Check the latch moves smoothly.

  4. 4

    Fit the new handles and cylinder

    Most locksets have an exterior handle/cylinder and interior handle that connect via a spindle through the door. Thread the spindle from the exterior side through the latch mechanism and connect the interior handle. Align the screw holes and tighten. Do not overtighten — the handles should move freely.

  5. 5

    Check alignment with the strike plate

    Close the door slowly and check that the latch engages cleanly with the strike plate on the door frame. If the latch does not line up, loosen the strike plate screws and adjust its position. Mark with pencil where the latch hits and reposition the plate accordingly.

  6. 6

    Test thoroughly before considering the job done

    Test the latch from both sides, test any locking mechanism, and test the key (for entry sets). Close the door and confirm it latches and opens correctly from both sides. Only leave when fully confident it works.

Rekeying vs replacingIf you have moved into a new home or lost a key, you can rekey the existing lock (change it to use a new key) at a locksmith for $30–80 per lock — much cheaper than replacing the whole lockset. Rekeying is the smart choice if the lock itself is in good condition.

Frequently Asked Questions

Measure the backset — the distance from the edge of the door to the centre of the lock hole. Standard Australian backsets are 60mm and 70mm. Also measure the bore hole diameter (usually 54mm). Most replacement locksets come with adjustable backsets or are available in both sizes. Taking the old latch to a hardware store and matching it is the simplest approach.
Call a locksmith for: mortise locks (complex, built into the door), smart locks with complex wiring, doors where the frame is damaged around the strike plate, or if the door is swollen or misaligned and not closing properly. Simple cylindrical lockset replacement is straightforward DIY. Deadbolt installation is also manageable DIY if you are comfortable drilling.