Some hosting risks cost you a bad review. This category costs lives. These are rare events relative to the total number of stays, but they're also almost entirely preventable with equipment that costs less than a night's cleaning fee.
What Airbnb actually requires (and what it doesn't)
It's worth being clear-eyed about this: Airbnb encourages smoke and CO detectors, and runs a program that ships free combination detectors to eligible hosts, but it does not mandate them platform-wide. Compliance is enforced by local law, not by Airbnb itself. Airbnb has stated that enforcement of detector requirements ultimately falls to city and local regulations, though it encourages every host to confirm a detector is installed.
Where Airbnb does apply pressure is disclosure. Listings that report having a detector are marked as such, guests can filter for it, and if a guest books a listing where no detector has been reported, Airbnb flags this to them before check-in. In practice, that means skipping a detector doesn't just create risk, it can quietly cost you bookings from the safety-conscious segment of guests who filter for exactly this.
If you're setting this hardware up, this is also the point where automating the alerts (rather than relying on a local siren alone) starts to matter, and IFTTT is the layer that connects a sensor going off to you actually finding out about it. If you don't already have an account, signing up is free.
Smart smoke and CO detectors
What changed in 2026: Google's long-running Nest Protect, previously the default recommendation in this category, has been discontinued. Its most direct successor is the First Alert SC5 Smart Smoke & Carbon Monoxide Alarm, which integrates with Google Home, supports both battery and hardwired installation, and includes remote silence and automatic self-tests. If you already have Nest Protect units installed, the SC5 uses the same Nest Weave mesh networking, so it can sit alongside your existing units rather than requiring a full replacement.
Budget WiFi option: The X-Sense XC03-W delivers real-time CO readings and phone alerts at roughly a third of the price of premium combo units, though it doesn't integrate with smart home platforms the way the SC5 does.
Whole-property hardwired: For a property with existing hardwired smoke detectors, a unit like the Kidde KN-COSM-IBA interconnects with what's already installed and adds CO detection with AC power plus battery backup, useful for larger properties where you want every alarm to trigger together rather than relying on someone hearing just the one nearest the source.
What actually matters when choosing one: - Dual sensor type (photoelectric plus ionization, or photoelectric plus electrochemical for CO) catches a wider range of fire types than a single-sensor unit. - Remote alerts, not just a local siren, since the whole point for a rental is knowing about a problem when you're not there. - Battery backup on hardwired units, so a power outage doesn't leave the property unprotected. - Placement: at least one detector per sleeping area or within each sleeping room, plus units near any fuel-burning appliance (furnace, gas water heater, gas dryer) and any attached garage.
A few IFTTT-native options are built specifically with short-term rentals in mind: iHaus smoke detectors can call or text you the moment an alarm sounds, Airthings adds CO2 monitoring on top of smoke and CO for ventilation issues, and Heiman covers straightforward push notifications if you're already using any of these ecosystems:
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Call Airbnb host when iHaus smoke alarm sounds
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Alert co-host by SMS when iHaus heat alarm
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Email Airbnb host for Airthings CO2 alert
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Get IFTTT notification when Heiman smoke alarm is triggered
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Water leak sensors: the third disaster category
Fire and CO get the headlines, but water damage is the failure mode most likely to actually hit a host's bottom line. We covered this in depth in our weatherproofing guide, but the short version: a leak sensor near water heaters, washing machines, and under sinks catches the problem within minutes instead of whenever the next guest or cleaner walks in, and a smart shutoff valve on the main line can cut water automatically before a slow leak becomes a flooded floor. Phyn, YoLink, and Aqara are three of the more straightforward IFTTT-native options here, whether you want a sensor tied to an automatic shutoff or a standalone leak alert.
If you're setting up smoke, CO, and leak protection for the same property at the same time, it's worth wiring them into the same alert system rather than three separate apps, so a 2 AM problem produces one notification you'll actually see instead of three you might not.
Frozen pipes are the other major cause of water damage in a rental, especially for a property that sits vacant during cold snaps. A Temp Stick sensor, or a thermostat like Nest or ecobee that alerts you or automatically holds a frost-prevention setpoint before pipes freeze, closes that gap:
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Notify Airbnb/VRBO hosts of Temp Stick freeze
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Alert Airbnb hosts when Nest temp risks freeze
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Hold ecobee for Airbnb freeze protection
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Set Nest min temp for Airbnb freeze (Google Nest Thermostat)
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The privacy line you can't cross
Airbnb's rules on in-unit monitoring are specific, and it's worth getting this right before you install anything: security cameras or any device that records audio or video inside a listing's interior spaces are banned outright, full stop. Smoke and CO detectors are explicitly fine, since they don't record audio or video, as long as their presence is disclosed in the listing. Noise-monitoring devices (which measure decibel levels, not audio content) are also allowed, but only outside bedrooms and bathrooms, and only with disclosure to guests.
Practically: stick to detectors that measure smoke, CO, temperature, and humidity, not anything with a microphone or camera, and add a line in your listing description confirming what's installed. This keeps you compliant and keeps the safety-conscious guests who filter for detectors from being surprised.
Automating the response, not just the alert
A detector that only sends you a push notification at 3 AM while you're asleep three states away isn't doing much. A few automations worth setting up once the hardware's in place, using services like FIBARO, abode, Notion, and Phyn: FIBARO + abode.
Applet: CO or smoke alarm triggers HVAC shutoff IF: Smoke or CO alarm activates THEN: Shut off HVAC automatically, since a compromised heat exchanger or blocked flue is often the CO source, and stopping the system limits further buildup
Applet: Alarm triggers emergency contact IF: Smoke or CO alarm activates THEN: Send an alert to you and a local emergency contact or co-host who can respond faster than you can from a distance
Applet: Leak sensor triggers water shutoff IF: A water leak sensor detects moisture THEN: Trigger your smart shutoff valve and notify you immediately
Applet: One-tap evacuation checklist IF: You press an emergency Button widget THEN: Create a prioritized checklist so a co-host or property manager knows exactly what to do next, without you having to talk them through it in the moment
These follow the same IF/THEN structure as the calendar and thermostat automations covered elsewhere in this series. The devices are different, but the logic connecting a sensor reading to an automatic response is the same pattern throughout.
No published IFTTT Applet currently ties a smoke or CO trigger directly to an HVAC shutoff action — that combination needs a custom multi-service Applet built directly in IFTTT rather than an off-the-shelf card. The alert, evacuation-coordination, and leak-to-shutoff automations below are all live, published Applets.
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Send an SMS when FIBARO detects carbon monoxide
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Call me if my alarm is triggered
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Shut off Phyn water when D-Link sensor detects a leak
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The bottom line
This is the one category of smart home device where the return isn't utility savings or guest convenience, it's the difference between a close call and a tragedy. A dual-sensor smoke and CO detector in every sleeping area, a leak sensor near your major water sources, disclosed properly in your listing, and wired into an alert system that actually reaches you or a local contact, covers the overwhelming majority of the risk for well under $200 in hardware. Given what's on the other side of that number, it's not really optional.
Ready to wire your detectors into an alert system that actually reaches you? Sign up for IFTTT free and connect your first Applet today.
FAQs
Does Airbnb require smoke and CO detectors?
Not platform-wide. Airbnb encourages hosts to install them and runs a program that ships free combination detectors to eligible hosts, but enforcement of detector requirements ultimately comes down to city and local regulations, not Airbnb itself.
Are security cameras allowed inside an Airbnb listing?
No. Any device that records audio or video inside a listing's interior spaces is banned outright. Smoke and CO detectors are fine since they don't record audio or video, and noise-monitoring devices (which measure decibel levels only) are allowed outside bedrooms and bathrooms with disclosure.
What happened to Nest Protect?
It was discontinued in 2026. The First Alert SC5 Smart Smoke & Carbon Monoxide Alarm is its most direct successor, using the same Nest Weave mesh networking, so it can sit alongside existing Nest Protect units rather than requiring a full replacement.
Where should smoke and CO detectors go in a rental?
At least one detector per sleeping area or within each sleeping room, plus units near any fuel-burning appliance (furnace, gas water heater, gas dryer) and any attached garage.
Can I automate my smoke, CO, and leak sensors together?
Yes. Wiring smoke, CO, and leak sensors into the same alert system means a problem produces one notification you'll actually see instead of three separate app alerts you might miss, and the same IF/THEN automation pattern connects all of them to an alert, a shutoff, or an emergency contact.
If you're experiencing a gas leak, smoke, or CO alarm right now, evacuate the property immediately and call emergency services before troubleshooting any device.
