The market for Matter-enabled smart locks is growing, with brands like Aqara, Nuki, and Yale establishing a strong presence for door access. Window security, however, has remained a largely overlooked category. Now, German hardware maker SIEGENIA is addressing this gap with its new “Smart window handle Gen. 2”, a motorized, keyless handle that operates on Matter-over-Thread, as first reported by HomeKit News.
The handle replaces a traditional, manually lockable window handle, offering a retrofit solution for increased security and convenience.
A smart Matter workaround: the “door lock” window
A key technical detail of the new handle is how it integrates with the current Matter ecosystem. Because the Matter specification does not yet have a dedicated category for “window handles” or “window locks,” SIEGENIA has used a clever workaround. According to its certification file, the device’s primary device type is a “Door Lock”.
Siegenia Smart window handle
The Smart window handle ZHSM0020-002010 by SIEGENIA features ESP32-C2 compatibility, offering Matter protocol support for cross-brand smart device communication.
This means that in platforms like Apple Home, Google Home, or SmartThings, the handle will appear and function as a standard lock, allowing users to lock and unlock it remotely or through automations. The product’s compliance file also indicates it exposes a binary sensor, which likely reports the window’s open/closed/tilted status.
This “door lock” workaround is likely a temporary measure. As we previously reported, the upcoming Matter 1.5 specification is expected to formally expand the “closures” category. This update is slated to add native support for a much wider range of devices, including windows, garage doors, gates, and shutters, which would eliminate the need for manufacturers to misidentify their products.
The file also notes support for Matter Binding, a feature that allows two Matter devices to be linked directly, though its specific application here is not yet clear. It could potentially be used to bind the handle directly to a Matter-enabled radiator thermostat, forcing it to turn off when the window is opened.
Retrofit-friendly design and installation
The “Smart window handle Gen. 2” is designed to be a simple replacement for existing handles on timber or PVC windows. The company states that the installation is identical to that of a conventional handle.
To ensure broad compatibility, it features a variable square spindle length (32-42 mm), allowing it to fit a wide range of window profiles. The device is battery-operated, using standard AAA batteries, and is available in two colors: signal white and anthracite black.
It appears the “Gen. 2” model uses the same core hardware and SKU as the previous smart version, as no separate Matter certification has been filed. This suggests the Matter functionality is the same as the existing product line, which share the same product ID.
The “Smart window handle Gen. 2” is available in white and black now for €89.90 ($103.33). Matter Alpha has reached out to SIEGENIA for comment on the gen 2 improvements and Matter features, but has yet to receive a response as of press time.
(Source: SIEGENIA; Image Source: SIEGENIA)
