I recently discovered Zigbee smoke and heat alarms. These are an amazing addition to Home Assistant as they allow:

• Knowing which room an alarm is triggered in!
• Remote alerting.
• Siren triggering.
• Remote hush.
• Battery monitoring.

In addition some types even allow room temperature monitoring which in my house has tracked very closely (within 0.5°C) with the Xiaomi BLE thermometers.

Two models I recommend are those made by Frient and the Heiman HS1SA-E Plus. Both are EN14604 certified (recognised in many countries including New Zealand) and work out of the box with Home Assistant.

The Frient alarms share many similarities with popular compact alarms made by Cavius, to the point I am convinced they are designed and made by the same people. Unfortunately unlike Cavius, Frient don’t offer a recess mount option so I’ve designed a printable one instead.

I printed mine in white ASA. Unfortunately the roll I used left a slightly yellowish finish, so a gentle sanding and quick spray with Tamiya TS-101 base white (no priming needed) made them match the alarm almost perfectly. It looks much closer than it does in the photo!

Use a 64mm (2 1/2″) hole saw in the ceiling and some thin double-sided foam tape to stick them in place. The alarm should fit and click into place.