Most Hosts Don’t Know Their Smoke Detectors Are Expired

I had a conversation with a host last fall that I keep thinking about.  She runs three properties, all in good shape, all well-reviewed. We were doing an insurance review and I asked her when she'd last replaced the smoke detectors. She thought about it for a second and said, "I honestly don't know. They were there when I bought the place."

That property sold in 2016.

We pulled the units off the ceiling.  Manufacture dates were 2013 and 2014. Nearly a decade old, sitting on ceilings in sleeping areas that guests were paying to use. She'd been testing them at the start of every season, getting a beep, and assuming they were fine. She didn't know smoke detectors have a ten-year service life. Most hosts don't.

Here's what I want you to understand: this isn't just a safety conversation. It's a claims conversation. And for short-term rental operators specifically, those two conversations aren't always the same.


The Safety Part Is Obvious. The Claims Part Usually Isn't.

You install smoke and carbon monoxide detectors because you care about your guests and because it's required. That's the right reason. But when I'm doing insurance audits, what I'm also looking at is how a detector program holds up in an investigation after something goes wrong.

When a fire or carbon monoxide incident occurs at a rental property, the adjuster isn't just looking at what caused the event. They're looking at what warning systems were in place and whether those systems were maintained to code. If guests were injured and no functioning detector alerted them, the absence of that detector becomes evidence. Not of a safety oversight. Of negligence. There's a difference, and the difference matters to what the claim costs.

A fire that woke guests up because a detector worked is a property damage claim. A fire that injured guests because no one was warned is a liability claim with a much higher ceiling. I've seen this play out in claims reviews repeatedly. The detector that works is evidence of reasonable care. The detector that wasn't there, or wasn't working, is evidence of the opposite.


Carbon Monoxide Is the One Most People Are Behind On

Smoke detectors have been legally required long enough that most hosts have them, even if they're expired. Carbon monoxide is different. The requirements have expanded significantly over the past ten years and they vary by state, but the general rule now is: if your property has a gas appliance, an attached garage, or a fuel-burning heating system of any kind, you almost certainly need a functioning CO detector under current code.

A lot of hosts don't have them. Not because they decided not to, but because the requirement is newer and nobody told them.

Here's what makes carbon monoxide specifically dangerous in a rental context. It's colorless and odorless. The symptoms are headache, fatigue, nausea, and confusion, which guests in an unfamiliar bed after a long drive or a couple of drinks might just attribute to not sleeping well. They may not recognize it as poisoning until it's already progressed. A functioning detector in or near the sleeping area interrupts that chain early. Without one, the situation can become very serious before anyone understands what's happening.

There's also a scenario I think about a lot for STR properties specifically. A gas appliance malfunctions or a flue gets partially blocked between the time one guest checks out and the next one checks in. The property sits unmonitored. The next guests arrive, spend a night, and whatever has been accumulating in the house affects them while they're asleep. A detector in the sleeping area makes that a medical monitoring situation. Without one, it can be something much worse.


"I Have Detectors" and "My Detectors Are Functioning" Are Not the Same Statement

This is the part that catches people, because most hosts believe they have working detectors. Some of them are right. But there are three specific ways a detector can be physically present and still fail when it matters.

The first is age. Smoke detectors have a recommended service life of ten years from the manufacture date, not the installation date. Carbon monoxide detectors typically run five to seven years depending on the sensing technology. The manufacture date is printed on the back of the unit. After that date, the sensing elements degrade and the device can no longer be relied on to function correctly. The host I mentioned earlier had units from 2013 and 2014. They beeped when tested. I wouldn't want to count on them to alert a sleeping family.

The second is battery status. Battery-powered units are adequate in most situations if the batteries are actually maintained. The problem in a rental property is that guests sometimes pull a battery at 2 AM to stop a low-battery chirp rather than replacing it, especially at an unfamiliar house on a short stay. They mean to mention it. They forget. Your pre-season battery check didn't catch it because it happened in August. Pre-booking battery confirmation, built into the turnover checklist rather than just the seasonal checklist, is the practice that closes this gap.

The third is placement. Most codes require smoke detectors on each level and in or near each sleeping area. One detector in a central hallway is not meeting the placement requirement for a bedroom at the far end of the second floor. Carbon monoxide placement requirements address proximity to sleeping areas specifically. If you've never checked your placement against the actual code requirements for your jurisdiction, the detectors you have may not be in the locations the code requires them to be.


What I've Seen in Claims

I want to be specific about what the difference looks like.

In Incident Report number seven in our series, a space heater fire broke out in a mountain cabin bedroom. The smoke detector functioned. The guests woke up and evacuated. Nobody was injured. The claim that followed was about structural damage, contents, and a smoke remediation job. It was significant, but it was a property damage claim with a defined ceiling.

The version of that incident without a functioning detector would have been a very different conversation. It would have involved guest injuries, a medical record, a personal injury attorney, and a liability claim that could have reached well into six figures. The detector changed which claim we were having.


Three Things to Do Before Your Next Booking

Flip your detectors over and look at the manufacture dates. Every unit in every sleeping area, every level, every unit in the property. If anything is more than ten years old on smoke, or past the manufacturer's stated service life on CO, replace it before the next guest arrives.

Walk the sleeping areas specifically and check placement. Confirm there's a functioning smoke detector and a functioning CO detector in or immediately adjacent to every bedroom. If a single hallway unit is doing all the work for four bedrooms, that's not adequate coverage and it's probably not code-compliant.

Add battery confirmation to your turnover checklist, not just your seasonal checklist. Test each unit before every booking cycle, document it, and treat a guest message about a chirping or disabled detector as something that gets addressed before the next check-in, not during the next seasonal inspection.

None of this is expensive. A complete detector replacement on a four-bedroom property costs a few hundred dollars in hardware and an afternoon to install. That's a fraction of a single night's booking revenue, and it's the difference between a property damage claim and a guest injury claim when something goes wrong.

The detectors that work are evidence of reasonable care. The ones that don't are evidence of something else. Make sure yours are the first kind before you find out they're the second.