Smart Locks for Aluminium Doors in NZ: A Buyer's Guide

Aluminium entrance doors are the default on a huge slice of New Zealand homes built since the 1990s, and they create a specific problem for anyone shopping for a smart lock. Most of the popular models you see online were designed for thicker timber doors with deep mortice pockets. Bolt one onto a 38 mm aluminium stile and you'll find the strike plate doesn't line up, the cylinder length is wrong, and the latch won't reach.

What makes an aluminium door different

Three things matter when you're spec'ing a smart lock for aluminium:

• Stile width. Most NZ aluminium doors have a 38–45 mm vertical stile next to the lock. Anything wider than that on the backplate will look wrong and may not seat flat.
• Door thickness. Standard aluminium entrance doors are around 40 mm thick. Smart locks built for 60–80 mm timber doors need long extension kits that aren't always supplied.
• Tempered glass inserts. Drilling new holes through the stile next to glazing is risky, pick a lock that uses the existing mortice cut-out.

Why the KS300 works on aluminium

The KS300 was built around the European mortice standard (DIN 18251), which is what most aluminium door manufacturers in NZ have used for the last 25 years. That means the lock body drops into the existing pocket without recutting. The narrow backplate suits stiles down to 40 mm. PIN, RFID card, proximity dot, app and physical key are all on board, so you don't lock yourself out if the battery dies.

If your door already has a Lockwood or similar mortice

You're in luck. Most of the older Lockwood and Whitco mortice cut-outs match the DIN footprint that the KS-series uses. A quick check: measure the backset, centre of cylinder to edge of door. If it is 60 mm or 70 mm you are very likely a direct fit. Send us a photo of the lock from the edge of the door before you order and we will confirm it.

Power and connectivity

The KS150, KS200, KS250 and KS280 run on 4 AA cells and the KS300 on 4 AAA, all rated 8 to 12 months under normal use. The KS300 can also do remote access through the Wi-Fi gateway, which is a separate purchase, and that is handy if you want to let in tradies while you're at work. The lock operates fully on Bluetooth without the gateway, which only adds the remote features.

Get the sizing right before you order

Use our Door Compatibility Guide to confirm fit before you buy. If you're not sure, send us a photo of your current lock from the edge of the door and we'll tell you which model fits.