--- service: "Publicasta" schema_version: "1.0" article_id: 720 title: "Your Nest Protect Is Expiring: How to Replace It Without Losing Whole-Home Fire Alerts" language: "en" default_language: "en" canonical_url: "https://publicasta.com/smart_home/nest_protect_expiry_smart_smoke_alarm_replacement_guide_2026?lang=en" json_url: "https://publicasta.com/smart_home/nest_protect_expiry_smart_smoke_alarm_replacement_guide_2026.json?lang=en" api_url: "https://publicasta.com/api/public/v1/channels/smart_home/articles/nest_protect_expiry_smart_smoke_alarm_replacement_guide_2026?lang=en" channel_url: "https://publicasta.com/api/public/v1/channels/smart_home" channel_articles: "https://publicasta.com/api/public/v1/channels/smart_home/articles" search_url: "https://publicasta.com/api/public/v1/search" documentation_url: "https://publicasta.com/api-docs#reading-publicasta" openapi_url: "https://publicasta.com/api-docs/openapi.json" published_at: "2026-09-28T10:20:31+00:00" updated_at: "2026-09-28T10:20:31+00:00" translations: - language: "ar" html_url: "https://publicasta.com/smart_home/nest_protect_expiry_smart_smoke_alarm_replacement_guide_2026?lang=ar" markdown_url: "https://publicasta.com/smart_home/nest_protect_expiry_smart_smoke_alarm_replacement_guide_2026.md?lang=ar" json_url: "https://publicasta.com/smart_home/nest_protect_expiry_smart_smoke_alarm_replacement_guide_2026.json?lang=ar" - language: "de" html_url: "https://publicasta.com/smart_home/nest_protect_expiry_smart_smoke_alarm_replacement_guide_2026?lang=de" markdown_url: "https://publicasta.com/smart_home/nest_protect_expiry_smart_smoke_alarm_replacement_guide_2026.md?lang=de" json_url: "https://publicasta.com/smart_home/nest_protect_expiry_smart_smoke_alarm_replacement_guide_2026.json?lang=de" - language: "en" html_url: "https://publicasta.com/smart_home/nest_protect_expiry_smart_smoke_alarm_replacement_guide_2026?lang=en" markdown_url: "https://publicasta.com/smart_home/nest_protect_expiry_smart_smoke_alarm_replacement_guide_2026.md?lang=en" json_url: "https://publicasta.com/smart_home/nest_protect_expiry_smart_smoke_alarm_replacement_guide_2026.json?lang=en" - language: "es" html_url: "https://publicasta.com/smart_home/nest_protect_expiry_smart_smoke_alarm_replacement_guide_2026?lang=es" markdown_url: "https://publicasta.com/smart_home/nest_protect_expiry_smart_smoke_alarm_replacement_guide_2026.md?lang=es" json_url: "https://publicasta.com/smart_home/nest_protect_expiry_smart_smoke_alarm_replacement_guide_2026.json?lang=es" - language: "fr" html_url: "https://publicasta.com/smart_home/nest_protect_expiry_smart_smoke_alarm_replacement_guide_2026?lang=fr" markdown_url: "https://publicasta.com/smart_home/nest_protect_expiry_smart_smoke_alarm_replacement_guide_2026.md?lang=fr" json_url: "https://publicasta.com/smart_home/nest_protect_expiry_smart_smoke_alarm_replacement_guide_2026.json?lang=fr" - language: "pl" html_url: "https://publicasta.com/smart_home/nest_protect_expiry_smart_smoke_alarm_replacement_guide_2026?lang=pl" markdown_url: "https://publicasta.com/smart_home/nest_protect_expiry_smart_smoke_alarm_replacement_guide_2026.md?lang=pl" json_url: "https://publicasta.com/smart_home/nest_protect_expiry_smart_smoke_alarm_replacement_guide_2026.json?lang=pl" - language: "ru" html_url: "https://publicasta.com/smart_home/nest_protect_expiry_smart_smoke_alarm_replacement_guide_2026?lang=ru" markdown_url: "https://publicasta.com/smart_home/nest_protect_expiry_smart_smoke_alarm_replacement_guide_2026.md?lang=ru" json_url: "https://publicasta.com/smart_home/nest_protect_expiry_smart_smoke_alarm_replacement_guide_2026.json?lang=ru" - language: "zh" html_url: "https://publicasta.com/smart_home/nest_protect_expiry_smart_smoke_alarm_replacement_guide_2026?lang=zh" markdown_url: "https://publicasta.com/smart_home/nest_protect_expiry_smart_smoke_alarm_replacement_guide_2026.md?lang=zh" json_url: "https://publicasta.com/smart_home/nest_protect_expiry_smart_smoke_alarm_replacement_guide_2026.json?lang=zh" --- # Your Nest Protect Is Expiring: How to Replace It Without Losing Whole-Home Fire Alerts > Google has stopped making Nest Protect, and many first-generation units are now reaching their ten-year expiry dates. Here is how to choose between First Alert’s SC5, conventional interconnected alarms, and a smart-home listener without weakening the safety system. A Nest Protect reaching its expiry date is not the same problem as an old smart plug going offline. The device is a certified smoke and carbon-monoxide alarm, and its sensors have a defined service life. When that life ends, the correct response is replacement, even if the alarm still appears in the Google Home or Nest app and still answers a manual test. ![A homeowner checks a replacement smoke and carbon-monoxide alarm beneath another alarm mounted in a bright hallway.](https://publicasta.com/storage/projects/14/pages/720/2026/09/bbd9e2c1-3ca4-4013-ada2-e4eb273a3f6e.webp) The timing is awkward because Google has ended new production of Nest Protect. Existing units continue to work through their expiry dates, but there is no current Google-made model to buy as a direct replacement. Google points US customers toward the First Alert Smart Smoke & Carbon Monoxide Alarm, also known as the SC5, which can join a home that still contains compatible Nest Protect units. That is the simplest migration for some households, but it is not automatically the best answer for every country, wiring arrangement, budget, or privacy preference. The practical question is therefore not “What is the newest smart smoke alarm?” It is “How do I preserve reliable, room-to-room warning first, then decide whether phone alerts and home-automation integration are worth the extra dependency?” ## First check the date, not the app status Google says second-generation Nest Protect units must be replaced ten years after their manufacture date to meet certification requirements. The expiry date can be found on the device itself or in the Nest or Google Home app under the device’s technical information. Google’s support documentation also says that a Protect will continue to chirp after expiry, whether or not it remains connected to Wi-Fi. That distinction matters. A green status in an app confirms that the alarm is communicating and that its self-checks have not reported a fault. It does not extend the certified life of the smoke or carbon-monoxide sensors. Treat the printed or app-reported “replace by” date as the controlling fact. If an alarm is already expired, has a failed sensor, has been exposed to a fire, flood, paint vapour, cleaning chemicals, aerosols, or another event that may have damaged its sensors, arrange a replacement immediately. Do not leave the ceiling position empty while comparing products. A temporary conventional alarm that meets local requirements is safer than a gap in coverage. The ten-year rule is not unique to Nest Protect. The US Fire Administration advises replacing the entire smoke alarm every ten years, testing alarms monthly, and using interconnected alarms so that one alarm sounds the others. Local building and fire codes can impose additional requirements, especially for hardwired alarms, rental properties, bedrooms, and homes with fuel-burning appliances. ## What Google’s replacement path actually preserves The First Alert SC5 is the closest official migration route for an existing Nest Protect installation. First Alert says its smart smoke and carbon-monoxide alarm is available in battery and hardwired versions, can send mobile alerts through its app, and can interconnect with selected First Alert and BRK alarms as well as Nest Protect. Google’s setup documentation describes adding the First Alert alarm to Google Home so that it can communicate with compatible Nest Protect units. That is useful, but “compatible” does not mean “the same product under a new name.” The SC5 moves the account and app relationship into a different manufacturer’s system. The alarm has its own setup and support path, and Google Home compatibility is part of the arrangement rather than proof that Google owns the complete safety experience. First Alert’s own documentation says Nest Protect and SC5 devices work together in the Google Home app, while other product and account functions remain tied to First Alert. The migration also has a boundary: it is not a license to keep expired Nest Protects in service indefinitely. A mixed installation can be sensible while different units reach their individual dates, but each alarm still has to be replaced when its sensors expire. Whole-home interconnection is valuable only if every device in the chain is current, installed correctly, and audible from sleeping areas. A useful way to think about the SC5 is as a bridge for an existing Google-oriented safety network, not as a reason to move every other part of the house into Google Home. You can buy it for the alarm problem and leave lighting, heating, cameras, and automations alone. ## Three replacement strategies ### 1. Stay close to Nest with First Alert SC5 Choose the SC5 when preserving the existing experience is more important than minimizing cloud dependence. This option makes the most sense when the home already uses several Nest Protect units, occupants rely on spoken room-specific warnings, or replacing the alarms one at a time is easier than redesigning the entire installation. The main advantages are the availability of both battery and hardwired models, the ability to mix those forms in an eligible installation, compatibility with selected Nest Protect units, and phone notifications when the smart functions are configured. First Alert also says the product uses smoke and carbon-monoxide detection in one alarm and supports interconnection so a triggered unit can sound the compatible alarms. The costs are less visible. You add another vendor account and another app. Remote notifications depend on networking and account services. Google Home integration does not turn the alarms into Matter devices or make them universally controllable from every local smart-home platform. A person choosing the SC5 for Home Assistant, Apple Home, or another controller should verify current support for the exact model rather than assuming that “works with Google Home” means broad interoperability. The SC5 is also a product-specific solution. Availability and electrical variants differ by market, so a model sold in the United States or Canada may not be suitable for a home elsewhere. Do not order a battery model simply because it is easier to find if local rules require hardwired, interconnected alarms in that location. ### 2. Replace the system with conventional interconnected alarms A conventional alarm system is often the strongest choice when the priority is dependable local warning with fewer online dependencies. The alarms can be interconnected by approved wiring or by a manufacturer’s approved wireless system, depending on the model and local rules. They do not need a Google account to sound, and a broadband outage does not remove their primary function. This approach gives up the Nest-style phone experience unless another device is added to listen for alarm sounds. That trade is not necessarily a failure. A life-safety alarm should be able to detect and sound locally even when the router, cloud service, phone, or automation server is unavailable. The important comparison is not “smart versus dumb.” It is “certified local detection and interconnection versus optional remote notification.” A well-installed set of conventional alarms may provide better resilience than a smart alarm that sends excellent notifications but is poorly placed, expired, muted, or dependent on an account nobody checks. If the home has existing hardwired alarms, select a replacement family that is approved for the existing interconnect method. Smoke alarms are not interchangeable merely because the ceiling box has the same shape. A new brand may require a different wiring harness, a compatible base, or a full replacement of the interconnected group. ### 3. Use ordinary alarms plus a smart listener A third route is to install certified local alarms and let a nearby smart speaker or home platform listen for the sound. Some Google, Alexa, and Apple products offer alarm-sound detection or emergency-notification features, with availability and subscription requirements varying by platform and country. This can be economical when the alarms are already due for replacement but the household still wants a remote notification. It can also be a useful layer for a renter who cannot change a hardwired system. But it should be treated as an additional notification path, not as the interconnection system and not as the thing that detects smoke or carbon monoxide. A listener can miss an alarm because of distance, closed doors, background noise, a speaker being unplugged, a microphone setting, a service outage, or a changed subscription. It cannot replace an alarm in a bedroom, hallway, or required location. It also introduces a privacy decision: a microphone-enabled device is being asked to identify a sound in the home and may send event information to a cloud service. Read the current feature and privacy terms before relying on it. ## How to compare the options without getting distracted by features Start with coverage. Draw a simple floor plan and mark every existing alarm, its type, its expiry date, and whether it is battery-powered or hardwired. Check that there is an alarm inside each bedroom, outside sleeping areas, and on every level as recommended by the US Fire Administration. The exact placement requirements depend on local rules and the building, but the principle is consistent: people must be able to hear an alarm while asleep. Next, identify the interconnect requirement. Ask whether all alarms must sound when one detects smoke or carbon monoxide, whether the home has a wired interconnect, and whether a wireless replacement uses a proprietary radio link. Do not assume that Wi-Fi, Bluetooth, Thread, Zigbee, or Matter automatically provides fire-alarm interconnection. General smart-home protocols and certified alarm-to-alarm signaling are different things. Then separate the safety functions from the convenience functions: - Safety functions include smoke and CO sensing, the local horn, power supervision, self-test behavior, expiry handling, and alarm-to-alarm interconnection. - Convenience functions include phone notifications, room names, spoken warnings, app history, remote testing, and automation triggers. A product should pass the first group before the second group affects the decision. If an app feature disappears, the alarm should still perform its core job. Finally, check the support boundary. Find the manufacturer’s replacement date, warranty terms, app requirements, supported countries, and current integration documentation. Google’s published Nest device security table lists Nest Protect as an older product and no longer a current Google Store product; the more relevant question for an owner is the alarm’s sensor expiry date, not whether a cloud dashboard still opens. ## Wiring is where a simple replacement can become unsafe Battery-powered replacement is usually a straightforward mechanical and configuration job, but a hardwired replacement is an electrical installation. The fact that a new alarm appears to fit the old mounting plate does not make every wire connection safe or legal. If a hardwired unit must be removed, the circuit should be isolated at the breaker and verified dead. A qualified electrician should handle unknown wiring, shared circuits, unusual voltages, damaged junction boxes, multi-unit interconnects, or any installation where the manual does not clearly match the existing system. Never connect a low-voltage smart-home device directly to mains wiring, bypass an alarm interconnect, or improvise a connector because two products look mechanically similar. For a replacement alarm, follow the exact manufacturer instructions for the country and model. Confirm whether the replacement is approved for the existing interconnect family. If the instruction says to replace the harness, base, or complete group, do that. Fire-safety equipment is a poor place to save a few minutes with an adapter of uncertain origin. Renters should ask the landlord or building manager before removing hardwired alarms or changing an interconnected system. In a multi-unit building, an alarm may be part of a required building-wide arrangement. A local smart-home improvement cannot take precedence over that system. ## Privacy and cloud dependency deserve a separate decision A smart smoke alarm normally sends less intimate information than a camera, but it still creates a record of devices, rooms, tests, alerts, and account activity. A household should know which company receives event notifications, whether the alarm requires an internet connection for remote alerts, how accounts are shared, and what happens if the app or service changes. The SC5’s Google Home compatibility is attractive to a Google household, but it should not be described as local-first protection. The alarm’s local siren and interconnect are the critical safety path; app alerts are an extra path. If internet access fails, the household should still receive a local alarm. If the account is locked, the household should still be able to test the physical device. For a privacy-conscious smart-home owner, a reasonable design is to keep certified alarms independent and add local monitoring only if the chosen hardware can receive an alarm state without weakening the certified system. Home Assistant can be useful for dashboards and reminders, but an automation server should never be the sole mechanism that tells people to evacuate. Avoid building a custom alarm listener that suppresses, delays, or rewrites the alarm signal. There is also a human privacy issue. Remote alerts may expose information about when people are home, which room detected an event, or whether a test occurred. Use separate household accounts where supported, enable strong account security, and share alerts with the people who need them rather than every smart-home guest. ## A practical migration plan 1. Record every alarm’s model, power type, location, manufacture date, and replacement date. Photograph labels before removing anything. 2. Check local fire and electrical requirements. Confirm the required number and placement of smoke and CO alarms, whether interconnection is mandatory, and whether a hardwired installation requires a licensed professional. 3. Decide whether local interconnection or app notifications is the primary requirement. It should be local interconnection and audible coverage. Treat remote alerts as secondary. 4. If choosing SC5, verify the exact battery or hardwired model, market availability, Google Home and First Alert app requirements, compatibility with any remaining Nest Protect units, and the manufacturer’s approved interconnect list. 5. If choosing conventional alarms, replace the full incompatible group when necessary rather than mixing products that cannot legally or reliably interconnect. 6. Install the new alarm before removing the old one from each location. Keep the replacement within the required coverage area and follow the manual for orientation and clearance from kitchens, bathrooms, heating appliances, and ventilation outlets. 7. Test every alarm from every sleeping area. Confirm that an alarm in one room causes the expected alarms to sound, and verify that household members know the sound and the evacuation plan. 8. Only after the local safety system passes its tests should you configure phone alerts, room names, smart-speaker listening, or home-automation notifications. 9. Remove expired units from service and dispose of them according to local electronic and battery-waste rules. Do not leave an expired alarm mounted as if it were active. 10. Put the next replacement dates on a household calendar. A smart-home dashboard can remind you, but a label and a calendar entry should not depend on a vendor continuing the same app. ## What I would choose in common household situations For a Google Home household with several healthy Nest Protect units reaching their dates at different times, the SC5 is the least disruptive path if it is sold and approved in that market. Replace units as they expire, confirm the mixed interconnect behavior after each change, and accept that the system now spans Google and First Alert accounts. For a household that is tired of cloud changes or is rebuilding after a Google migration, certified conventional interconnected alarms are the cleaner long-term foundation. Add remote notifications only as a separate layer. This choice is less exciting, but it reduces the number of services that can affect the basic warning. For a renter or someone unable to alter the wiring, use a code-compliant replacement approved for the existing installation and ask the responsible property owner to handle the system. A smart speaker listening for alarms can supplement notifications where supported; it should not be used to justify removing required alarms or breaking an interconnect. For a Home Assistant user, resist the temptation to turn the replacement into a protocol-shopping exercise. Matter, Thread, Zigbee, and local APIs may be relevant to lighting and sensors, but none of those labels by itself answers the life-safety questions. Choose the alarm family first, then check whether monitoring or reminders can be added without making the alarm dependent on Home Assistant. ## The sensible bottom line Nest Protect’s end of production is inconvenient because it turns a familiar smart-home product into a replacement-planning problem. The answer is not to keep an expired unit alive, and it is not to buy the first device that promises a phone notification. Check the certified expiry date, preserve audible coverage and interconnection, match the power and wiring requirements, and treat cloud alerts as an enhancement. The First Alert SC5 is a plausible official successor for homes that want to remain close to Google Home, especially when existing Nest Protect units must be replaced gradually. A conventional interconnected system can be the better choice when reliability, local operation, cost, or reduced account dependence matters more. The smart part is optional. The alarm, the coverage, the power, and the escape plan are not. ### Sources and reporting notes This article uses Google’s current Nest Protect expiry and interconnection documentation, First Alert’s SC5 product and compatibility information, US Fire Administration guidance on alarm placement and replacement, a Google Nest announcement confirming the end of new Nest Protect production, and recent owner discussion about expiring installations. Product availability and local code requirements can change, so verify the exact model and rules before installation. [Google: Learn when to replace your Nest Protect](https://support.google.com/googlehome/answer/9249296?hl=en-GB) [Google: Wireless interconnect for Nest Protect](https://support.google.com/googlehome/answer/9232615?hl=en) [First Alert: Smart Smoke & CO Alarms](https://www.firstalert.com/pages/sc5-smart-smoke-co-detection) [Google: Set up the First Alert Smart Smoke & Carbon Monoxide Alarm](https://support.google.com/googlehome/answer/16324143?hl=en-CA) [US Fire Administration: Smoke Alarms](https://www.usfa.fema.gov/prevention/home-fires/prepare-for-fire/smoke-alarms/) [Google Nest Community: Saying Goodbye to Nest Protect](https://www.googlenestcommunity.com/t5/Blog/Saying-Goodbye-to-Nest-Protect/ba-p/708074) [Home Assistant Community discussion: Replacing expiring Nest Protects](https://www.reddit.com/r/homeassistant/comments/1wp5m20/replacing_expiring_nest_protects_in_home/)