Smart Lock for Composite Doors Guide¶

Guide to smart locks for UK composite doors covering solid timber core compatibility, euro cylinder sizing, multipoint lock integration, and specific considerations for composite door profiles.

Composite Door Smart Lock Compatibility¶

Composite doors are increasingly popular in UK homes, combining a solid timber core with uPVC skin for improved insulation. They use the same euro-profile cylinder as uPVC doors, making most smart locks compatible. However, composite doors have specific considerations: door thickness (44-52mm) is often more than uPVC, the locking mechanism is usually a high-security multipoint system (ERA, Avocet, Mila), and the door construction can dampen wireless signals. Popular smart locks for UK composite doors: Yale Conexis L1 (£180-£250, tested with ERA composite doors), Ultion Smart (£200-£300), and Nuki Smart Lock 3.0 (£250-£350). Cylinder size for composite doors is typically 35/45mm or 40/50mm - thicker than standard uPVC.

Installation for Composite Doors¶

Step 1: Measure the existing cylinder carefully - composite door cylinders are often asymmetric (e.g. 35/45mm). Step 2: Remove the retaining screw and slide the cylinder out. Note the cam position. Step 3: If the existing cylinder has a distinctive cam shape (Mila cam or Avocet cam), verify your smart lock includes the correct cam adapter. Step 4: Insert the new smart lock cylinder with correct cam alignment. Step 5: Secure with retaining screw - composite door profiles may need a slightly longer screw. Step 6: Mount the external keypad and internal motor unit. Composite door construction can make cable routing more challenging - use the provided routing tool. Step 7: Test lock operation - composite door multipoint locks require smooth engagement. Step 8: Complete app setup and test all functions. The dense construction may reduce wireless range slightly - position your WiFi router within 10m of the door.

Specifications and Comparison¶

Composite Door Feature	Specification	UK Consideration
Door Thickness	44-52mm	May require longer cylinder
Cylinder Size	35/45mm or 40/50mm	Measure before purchase
Multipoint Brand	ERA, Avocet, Mila, Yale	Check compatible lock cam
Signal Loss	10-20% vs uPVC	Dense door core affects WiFi/BT
Retaining Screw	Location may differ	Check door edge carefully

FAQ¶

Are composite doors compatible with smart locks?: Yes - composite doors use standard euro-profile cylinders just like uPVC doors. Most UK smart locks are compatible.
Is the cylinder on a composite door different from uPVC?: Composite doors often use longer cylinders (35/45mm or 40/50mm) due to greater door thickness.
Will the composite door reduce WiFi signal?: Composite doors have a denser core which may reduce wireless signal by 10-20% compared to uPVC. For more information see our Smart Lock for uPVC Doors Guide.

Last updated: 2026-05-31.

External Resources¶

For further information consult authority guidelines at the Ofcom.