10 Best Hardwired Smoke Detector 2025 in the United States

The FIRST ALERT BRK SC9120FF Smoke and Carbon Monoxide Detector is designed to provide comprehensive safety for your home. It features dual sensing technology, using both an electrochemical sensor for carbon monoxide and an ionization sensor for smoke detection, which ensures accurate identification of potentially hazardous conditions. The unit's interconnectivity allows it to connect with other BRK or First Alert detectors, creating a network of alarms that simultaneously alert you to danger, enhancing home safety.

The hardwired setup with a battery backup ensures continuous monitoring, even during power outages, which is a crucial feature for uninterrupted protection. The alarm volume is notably loud at 85 decibels, providing a clear and unmistakable warning in case of smoke or CO detection. Additionally, indicator lights on the unit's face ensure you can visually confirm the presence of smoke or carbon monoxide.

Although it lacks smart features like app connectivity or voice alerts, it compensates with a user-friendly design. The single test/silence button simplifies operation, while the side-load battery compartment and tamper-resistant locking brackets contribute to straightforward installation. Rigorously tested to meet UL standards, this detector demonstrates reliability and quality, backed by a trusted brand with decades of experience in home safety. The ease of installation further makes it suitable for quick setup, whether by professionals or DIY homeowners. Its strong performance in essential detection and safety makes it a highly reliable option for most households.

The Kidde Hardwired Smoke Detector uses ionization sensing technology, which is effective at detecting invisible fire particles quickly, making it a solid choice for general home fire safety. It runs on your home's 120V electrical system but includes a 9V battery backup, so it keeps working even during a power outage — a key feature for peace of mind. The alarm is loud at 85 decibels, which is enough to wake most people if there’s a fire.

You can connect up to 24 Kidde devices, including smoke, carbon monoxide, and heat alarms, allowing your whole home system to alert you at once. Installation is made easier by a front-load battery door for quick battery changes and a handy test/silence button right on the device to check functionality or temporarily stop false alarms. However, this model does not have advanced smart features like app connectivity or voice alerts, which some newer detectors offer.

It is designed to handle temperatures up to 100 degrees Fahrenheit and fits standard home conditions without issues. This straightforward, reliable smoke alarm is suitable for most households, though those seeking smart home integration might want to explore other options. The product is backed by a 10-year limited warranty, but since it has been discontinued, replacement parts could be harder to find over time.

The Google Nest Protect is a hardwired smoke and carbon monoxide detector that uses an electrochemical sensor, known for reliable detection of harmful gases. It is powered by lithium metal batteries, which means it has a battery backup in case of power outages, offering extra safety. This model supports interconnectivity, so multiple alarms in your home can communicate and sound together, helping you react faster during an emergency. The alarm volume is designed to be loud enough to alert you effectively.

A standout feature is its smart capabilities — it can send alerts to your phone, test itself automatically, and provide voice alerts that tell you the type and location of the danger, making it easier to understand the situation. Installation is fairly straightforward for someone comfortable with wiring, and it comes with a wall plate and necessary accessories. On the downside, while it is labeled as wired, it still relies on batteries, which means you’ll need to replace them periodically. Also, its price point tends to be on the higher side compared to basic smoke detectors.

This alarm is an excellent choice for homeowners looking for reliable detection with smart connectivity and clear alerts, especially if you want peace of mind from both smoke and carbon monoxide threats.