Smoke Alarms

Install smoke alarms on every level of your home, including the basement, plus one in each bedroom and outside all sleeping areas. A two-story home with three bedrooms typically needs at least five alarms. Large homes may require more based on layout and code requirements.

Choose a smoke alarm based on where it will be installed and the features you need. Options include hardwired or battery-operated models depending on your home’s installation method, 10-year sealed batteries, voice alerts, and combination smoke and carbon monoxide detectors. For large spaces, consider interconnected alarms for whole home alerts.

Yes, different types of smoke alarms can be used together in a home, but compatibility depends on several factors:

• Sensor types: Using a mix of photoelectric and ionization alarms — or dual sensor units — is recommended for broader fire detection coverage.
• Features: Smoke-only and combination smoke & CO alarms can be used together throughout the home, based on room placement and safety needs.
• Power sources: Battery-operated and hardwired alarms can coexist in the same home, but they won’t function as a connected system unless specifically set up and designed to do so.
• Interconnect compatibility: For interconnected systems, alarms must be compatible — ideally from the same brand and series — to ensure they communicate properly. Mixing alarms from different manufacturers may prevent alarms from triggering together, even if the wiring is the same. See product manual for compatible models.

You should test your smoke alarm regularly to help make sure it’s working properly. If your alarm does not test correctly, replace the unit immediately. See the product manual for specific information on how and when to test your alarms.

First Alert smoke alarms should be replaced at least every 10 years. Check the manufacturer date on the back of the alarm and if it is 10 years old or older - the entire unit should be replaced—even if it still seems to work—as the smoke sensors can lose sensitivity over time.