By Door Style

The door decides the lock. Before access methods, app platforms or finishes come into it, the door format sets a hard limit on what can physically be fitted. Pick your door type below and the range narrows to what will actually work.

What each door format constrains

Door format	The binding constraint	Typical outcome
Regular front door	Backset (60 mm or 70 mm), door thickness, existing prep.	The widest choice of any format. Most deadbolt and lever smart locks fit.
Security screen, hinged	Clearance between screen and main door, and screen stile width.	Purpose-built screen locks only. Measure the gap first.
Glass sliding door	Hook bolt geometry and stile width on the sliding leaf.	Hook bolt mortice format, usually a slimline body.
Frameless glass, hinged	No stile to drill. The lock must clamp or use a patch fitting.	Patch fitting or clamp-mount locks only.
Narrow frame or stile	Stile width, commonly under 50 mm on aluminium.	Slimline body with a narrow mortice case.
Vertical push or pull handle	Existing handle position clashes with the lock escutcheon.	Three viable pathways, none of them obvious.
External gate	Direct weather exposure and salt air. IP rating and material.	IP-rated bodies, marine-grade fixings.
Fire door	AS 1905.1 certification for that door type, plus penetration limits.	Certified locks only. Not a DIY job.
Internal door	No weather exposure, so the constraint is usually just backset.	Retrofit and lower-cost formats become viable.

Measure these five before you shortlist

Backset - door edge to spindle or cylinder centre. Usually 60 mm or 70 mm.
Door thickness - measured on the leaf, not the frame.
Stile width - the vertical frame member the lock sits in. Critical on aluminium and screens.
Clearance - the gap between a security screen and the main door leaf, if there is one.
Handing - which way the door swings and which side the hinges are on.

If you are unsure of any of these, Chapter 02 - Measuring Your Door walks through each measurement with diagrams. Getting the backset wrong is the most common reason a lock has to be returned.

Related categories

All Smart Locks · By Access Method · Digital Mechanical Locks · Mortice Locks

Common questions

My door is aluminium. Does that change things?
Yes, considerably. Aluminium doors usually have a narrow stile, often under 50 mm, which rules out standard lock bodies. Start with Door with Narrow Frame and check the stile measurement against the lock body depth.

I have both a main door and a security screen. Which one takes the smart lock?
Either, and sometimes both. Fitting to the screen keeps the main door untouched but needs adequate clearance behind the screen. Dual unlock products open both in one action. How dual unlock works.

How do I know if my door is a fire door?
Look for a compliance tag on the hinge edge or top edge of the leaf. If there is a tag, treat it as a fire door and do not drill it until the certification path is confirmed. Identifying a fire door.

Guides and reference

Ch 02 - Measuring your door · Ch 04 - Door type compatibility matrix · How to measure backset · Determining door handing · What bolt throw means