Replacing a Lockwood 355 handleset is well within reach for a confident DIYer. Unlike electrical or plumbing work, fitting a door handleset is not restricted work under New Zealand law, so no licence is required. That said, getting the installation right matters for your home's security, so it pays to follow the correct process.
What Is the Lockwood 355?
The Lockwood 355 is a popular tubular latch handleset widely used on interior and exterior doors throughout New Zealand. It features a lever handle, a tubular latch mechanism, and is designed to suit standard door preparations. Lockwood is a well-established NZ brand, and replacement parts and compatible handlesets are readily available at hardware stores.
Tools and Materials You'll Need
Before you start, gather the following:
- Phillips head and flat-blade screwdrivers
- Tape measure
- Pencil
- Chisel (if adjusting the latch faceplate recess)
- Replacement Lockwood 355 handleset (or compatible equivalent)
- Optional: cordless drill with hole-saw attachment (if enlarging or repositioning holes)
Check the backset measurement of your existing latch — this is the distance from the edge of the door to the centre of the handle spindle hole. The Lockwood 355 commonly comes in 60 mm or 70 mm backset options. Buying the wrong backset is the most common DIY mistake, so measure twice before purchasing.
Step-by-Step Replacement Guide
1. Remove the Old Handleset
- Open the door and locate the screws on the interior rose or backplate. On some models, there is a small grub screw or cover cap hiding the fixing screws — check around the base of the lever.
- Unscrew and remove both lever handles.
- Unscrew the latch faceplate from the door edge and slide the latch body out.
2. Check the Door Preparation
Inspect the spindle hole, latch hole, and faceplate recess in the door edge. If you're fitting a like-for-like Lockwood 355 replacement, these should align perfectly. If the faceplate recess is slightly off, use a sharp chisel to carefully deepen or widen it so the new faceplate sits flush.
3. Fit the New Latch
- Slide the new latch body into the door edge hole, ensuring the angled face of the latch bolt faces the direction the door closes (towards the striker plate).
- Screw the latch faceplate flush to the door edge.
4. Fit the Handles
- Thread the square spindle through the latch mechanism from one side.
- Fit both lever handles onto the spindle, aligning the rose or backplate with the door face.
- Tighten all fixing screws evenly — do not overtighten, as this can bind the lever action.
5. Check the Striker Plate
Close the door slowly and check that the latch bolt engages cleanly with the striker plate on the door frame. If it doesn't align, you may need to reposition the striker plate slightly. Most striker plates have a small amount of adjustment available by enlarging the recess with a chisel.
6. Test Before Finishing
Test the handle action from both sides, and check the door latches and releases smoothly. If the lever feels stiff or the latch drags, double-check that all screws are evenly tightened and the latch faceplate is fully flush.
Keyed vs. Non-Keyed Handlesets
If your Lockwood 355 is a keyed entry handleset (i.e., it has a key cylinder for an exterior door), the process is similar, but you'll also need to transfer or replace the key cylinder. If you want the new lock keyed alike to your other locks — so one key opens everything — a locksmith can rekey the cylinder for you. This is a smart option for exterior doors and is worth the small cost.
Building Code and Security Considerations
For exterior doors, New Zealand's MBIE Building Performance guidelines and the NZ Building Code (in particular Clause F4 relating to safety) expect that door hardware maintains the security and weathertightness of the building envelope. A standard like-for-like handleset replacement on an existing door does not require a building consent, but always confirm with your local council if you are unsure — especially if you are changing the door itself or making structural modifications.
For rental properties, landlords should also be aware of Tenancy Services Healthy Homes requirements, which include ensuring all exterior doors are lockable and secure.
When to Call a Professional
While replacing a Lockwood 355 handleset is DIY-friendly, consider calling a qualified locksmith if:
- The door frame or lock mortise is damaged and needs repair before a new handleset will fit correctly.
- You want the lock rekeyed to match other locks in your home.
- You're upgrading to a deadlock or multi-point locking system, which involves more complex door preparation.
- The door is a fire door — fire door hardware must comply with specific standards and should be installed by someone familiar with those requirements.
- You're not confident in the result — a poorly fitted lock on an exterior door is a security risk.
A qualified locksmith can also advise on whether the Lockwood 355 is the best option for your door and security needs. You can find licensed locksmiths in your area on tradedirectory.co.nz.
