Smart locks replace or augment the cylinder-and-key mechanism in a standard deadbolt with an electronic locking mechanism controlled by a keypad, smartphone, or proximity credential. For residential use in Canada, the practical considerations include door hardware compatibility, battery life in cold conditions, connectivity method, and how the lock behaves when network or power is unavailable.
Types of Smart Locks by Credential Method
Keypad Locks
Keypad locks replace the exterior key cylinder with a numeric or alphanumeric keypad. Users enter a PIN code to unlock. Multiple codes can typically be programmed, making it practical to assign temporary codes for contractors, cleaners, or guests without issuing a physical key. Codes can often be deleted remotely when access is no longer needed.
Keypad locks are among the most straightforward smart lock types: they do not require a smartphone app, Wi-Fi connection, or hub to function. The trade-off is that access management happens at the device or through a connected app, depending on the model.
Bluetooth Locks
Bluetooth-enabled locks communicate with a smartphone over short range, typically up to 10 metres. When a paired phone comes within range, the lock can unlock automatically (auto-unlock) or on a tap within the app. Bluetooth locks do not require a home Wi-Fi network or cloud connection for basic operation. Remote unlock from outside Bluetooth range is not possible without an additional bridge or hub device.
Z-Wave and Zigbee Locks
Z-Wave and Zigbee are mesh radio protocols commonly used in home automation systems. Locks using these protocols integrate with compatible smart home hubs — including platforms like SmartThings, Home Assistant, or Amazon Echo with a hub — allowing remote access, scheduling, and integration with alarm systems or cameras. Both protocols use frequencies different from Wi-Fi (Z-Wave operates at 908.42 MHz in North America), which reduces congestion from other wireless devices.
Wi-Fi Native Locks
Some locks include built-in Wi-Fi for direct cloud connectivity without a separate hub. This simplifies the setup process but introduces a dependency on cloud service availability. If the manufacturer’s cloud servers are unreachable, remote features may be unavailable. Most Wi-Fi locks retain local keypad or app functionality even when the cloud is offline.
Biometric Locks
Biometric locks use fingerprint readers or, in some higher-end models, facial recognition. Fingerprint reading in cold conditions can be affected by gloves, dry skin, or moisture on the sensor. Models intended for outdoor residential use typically include a keypad backup method. Biometric credentials are stored on the device itself in most residential models.
Door Hardware Compatibility
Most smart locks in the Canadian market are designed to fit standard ANSI/BHMA backset dimensions: 60mm (2-3/8 inch) and 70mm (2-3/4 inch) are the most common. Before purchasing, measure the backset (distance from the door edge to the centre of the bore hole) and check whether the door is pre-drilled for a deadbolt. Some smart locks replace only the interior thumbturn and retain the existing exterior cylinder; others replace the entire lockset.
Door thickness is a factor: most locks are designed for doors between 35mm and 50mm thick. Thicker exterior doors or doors with decorative hardware may require extension kits or may not be compatible with certain models.
Battery Performance in Cold Climates
Smart locks are battery-powered, typically using four AA batteries. Standard alkaline batteries lose capacity at low temperatures. In sustained cold — a front door in a cold porch or an uninsulated garage entry — alkaline batteries may drain noticeably faster than manufacturer estimates, which are typically based on moderate temperature conditions. Lithium AA batteries maintain capacity better in cold temperatures and are often recommended for outdoor locks in Canadian climates.
Most smart locks include low-battery alerts via app notification or audible signal. Some models include a 9V battery terminal on the exterior for emergency power if the internal batteries are depleted, allowing one-time unlock to replace the batteries.
Fail-Safe and Fail-Secure Operation
When power or connectivity is lost, a lock’s default state matters. Most residential smart locks are “fail-secure” — they remain locked when power is lost. The keypad and physical key (if the lock retains a key cylinder) continue to function because they operate the locking mechanism directly. Network connectivity loss typically only affects remote access features, not local operation.
Integration with Home Security Systems
Smart locks can integrate with residential alarm systems when both use compatible protocols. Z-Wave locks integrated with a compatible alarm panel can trigger actions: arming the system when the door locks, or sending an alert when a specific access code is used. Integration requirements vary by panel manufacturer; checking protocol compatibility before purchase avoids mismatches.
Installation Considerations
Most smart lock installations are designed for homeowner installation using standard tools — typically a screwdriver and drill. The main variables are door thickness, bore hole diameter (typically 54mm for the main bore), existing hardware, and deadbolt backset. Manufacturers usually include installation templates and shims for common configurations.
In rental properties or condominiums, building rules may restrict lock replacements. Some condominium corporations require approval for changes to suite door hardware that interfaces with a master key system. Smart locks that retain the existing exterior cylinder (interior-only replacement models) may be acceptable in situations where the exterior appearance must be maintained.
Security Grade Ratings
ANSI/BHMA grades (Grade 1, 2, 3) apply to the mechanical strength of the deadbolt hardware, not the electronic components. Grade 1 is the highest residential mechanical rating for deadbolts and covers cycle testing, security testing, and force resistance. The electronic components — Bluetooth radios, Wi-Fi modules — are not part of the ANSI/BHMA grading. Evaluating a smart lock involves both the mechanical grade of the underlying deadbolt and the security of the software and credential management.