First Alert SC5 Hardwire Smart Smoke & CO Alarm vs Google Nest Protect (Battery)

The Google Nest Protect (Battery) wins overall, thanks to a much deeper sensor suite, wider connectivity and integrations, a built-in light, self-testing and an automatic pathlight. The First Alert SC5 Hardwire Smart Smoke & CO Alarm's main advantage is its longer warranty.

Sensor breadth and power source. The Google Nest Protect (Battery) adds occupancy, temperature, humidity, ambient-light and motion sensing on top of smoke and CO, and runs entirely on AA batteries, while the First Alert SC5 Hardwire Smart Smoke & CO Alarm sticks to smoke and CO sensing and is mains-powered with a battery backup, requiring existing alarm wiring.

The First Alert SC5 Hardwire Smart Smoke & CO Alarm carries a considerably longer manufacturer warranty than the Google Nest Protect (Battery).

Yes. Both include steam-check technology that uses sensor readings to distinguish cooking smoke or shower steam from an actual fire, cutting down on nuisance alerts.

Homeowners who already have hardwired alarm circuits and want a straightforward smoke and CO alarm backed by a long warranty, without needing the Nest Protect's extra sensors.

Buyers without existing alarm wiring who want the fullest sensor suite available, including motion and ambient-light sensing, a pathlight, and self-testing, all reachable through Google Home or Home Assistant.