Smoke and carbon monoxide detectors in rentals: a small landlord checklist

Start with the boring truth: alarms are not "set and forget"

Smoke alarms and carbon monoxide alarms are cheap compared with almost everything else in a rental property. That is why they get ignored.

They are not a renovation. They are not a leasing strategy. They are not going to make the listing photos better. They are just small plastic devices on ceilings and walls that can become very important at 2:14 a.m.

For a self-managing landlord, the goal is simple:

• The right alarms are installed in the right places
• They work when the tenant moves in
• They are tested on a reasonable schedule
• Expired, missing, disabled, or chirping units are handled quickly
• Your records show what you did

This is not a substitute for your local code. Smoke and carbon monoxide rules vary by state, city, property type, building age, and whether the home has fuel-burning appliances or an attached garage. Use this as an operating checklist, then confirm the exact requirements for your rentals.

Know which devices you are talking about

Landlords sometimes use "smoke detector" as shorthand for every alarm in the house. Separate the categories.

Smoke alarms detect smoke from fire. Most rentals need them in sleeping areas, outside sleeping areas, and on each level, but your local rule may be more specific.

Carbon monoxide alarms detect carbon monoxide, an invisible and odorless gas that can come from malfunctioning fuel-burning equipment, fireplaces, gas ranges, water heaters, furnaces, boilers, or attached garages. Many jurisdictions require CO alarms near sleeping areas when the property has a fuel-burning appliance, fireplace, or attached garage. Some require them more broadly.

Combination alarms detect both smoke and carbon monoxide in one unit. They can be useful, but they still have to be placed where each function makes sense. A combination alarm installed in a bad location is not automatically good compliance.

Also note the power source:

• Battery-only
• Sealed 10-year battery
• Hardwired with battery backup
• Interconnected alarms, where one alarm triggers the others

Do not assume every device in an older house is equivalent. A yellowed hardwired alarm from three paint jobs ago may be expired even if the little green light is still on.

Walk the property like you are making a map

Before buying replacements, make a detector map for each unit.

Use a simple table:

You are looking for gaps:

• No alarm inside or near sleeping rooms where required
• No alarm on a level of the home
• No CO alarm near sleeping areas when the property has gas, oil, propane, wood-burning equipment, or an attached garage
• Alarms installed too close to kitchens, bathrooms, ceiling fans, vents, or dusty utility areas
• Devices hidden by furniture, curtains, shelving, or tenant belongings
• Missing battery doors, removed batteries, disconnected hardwired units, or painted-over covers
• Units past the manufacturer's replacement date

Use the manufacturer's instructions for placement distances. The details matter. A smoke alarm too close to a bathroom may nuisance-trip from steam until the tenant disables it. A CO alarm installed in the wrong place may not protect sleeping occupants as intended.

Replace first, debate later

If a detector is missing, expired, painted over, physically damaged, disconnected, or unreliable, replace it.

Do not spend three weeks trying to prove whether the tenant removed the battery. Get the property safe first. Then decide whether there is a lease issue, tenant charge, or follow-up conversation.

Good replacement habits:

• Use sealed 10-year battery alarms where allowed and practical
• Match hardwired alarms with compatible replacements
• Replace all interconnected alarms with compatible units, not random singles
• Write the install month and year on the back or side if the manufacturer label is hard to read
• Photograph the installed device and the date label
• Keep receipts with the property file

Hardwired alarms deserve extra care. If you are not comfortable replacing them, hire an electrician or qualified handyman who understands the system. The same goes for interconnected alarms. A rental is not the place to learn wiring by trial and error.

Build testing into the rental calendar

Testing is where many small landlords get vague. "The tenant will tell me if it chirps" is not a system.

Use predictable checkpoints:

Before move-in

Test every smoke and CO alarm before the tenant receives keys. Document the result in the move-in condition report.

Note:

• Date tested
• Location of each device
• Whether it sounded
• Battery replacement, if any
• Replacement date or manufacture date when visible
• Any device installed or replaced

This matters because it proves the property was delivered with working life-safety equipment.

During annual inspections

When you do a routine inspection, include alarms in the checklist. If local law or your lease limits testing in occupied units, follow those rules. Otherwise, test, photograph, and record the result.

Do not make the inspection about blame. Say plainly:

I am checking the smoke and carbon monoxide alarms as part of routine safety maintenance.

That sentence is enough.

During turnovers

Turnover is the easiest time to fix placement problems. Beds are gone, furniture is moved, and you can access ceilings, hallways, basements, garages, and utility rooms without coordinating around a tenant's schedule.

Use turnover to:

• Replace expired units
• Add missing alarms
• Move poorly placed alarms
• Clean dust from covers
• Replace batteries where applicable
• Confirm bedroom changes have not created a new sleeping-area requirement

If a bonus room became a bedroom during the last tenancy, your alarm layout may need to change before the next one.

When a tenant reports chirping

A chirp is not a personality test for the tenant. It usually means low battery, end of life, dust, power interruption, or device failure.

Reply quickly:

Thanks for letting me know. Please send a short video or photo of the alarm that is chirping so I can identify the location and model. Do not remove or disable the alarm. I will arrange battery replacement or device replacement.

If your lease makes tenants responsible for ordinary battery replacement, you can still guide the process. If the unit is sealed, expired, hardwired, or repeatedly chirping, treat it as a landlord maintenance issue.

Tell tenants what not to do

Tenants disable alarms for predictable reasons: cooking smoke, shower steam, low-battery chirps, beeping after a power outage, or a device installed in a bad spot.

Your lease or welcome materials should say:

• Do not remove, cover, disconnect, paint, or disable smoke or CO alarms
• Report chirping, missing, damaged, or malfunctioning alarms promptly
• Do not remove batteries except to replace them if the lease assigns that duty
• Notify the landlord before using appliances or rooms in a way that may require additional alarms
• Keep alarms accessible and not blocked by furniture, shelves, or decorations

Keep the wording practical, not theatrical. A tenant who is tired of false alarms at dinner needs a fix, not a lecture. If nuisance alarms keep happening, check placement, ventilation, and device type.

Keep a detector log

For each property, maintain one simple log. It can be a spreadsheet, a note in your property file, or a maintenance record in your software.

Track:

• Property and unit
• Device location
• Device type
• Power source
• Brand/model, if easy to capture
• Manufacture date or replacement date
• Date tested
• Test result
• Battery replaced
• Device replaced
• Photos or receipt links
• Tenant report or work order reference

The log is useful in three situations.

First, it prevents memory-based maintenance. You should not have to remember whether the upstairs hallway alarm was replaced last year or three tenants ago.

Second, it helps with insurance, sale, refinance, and inspection questions. A clean record is easier to hand over than a pile of receipts.

Third, it protects the landlord-tenant relationship. If a tenant says an alarm never worked, you can respond from the file instead of from defensiveness.

Common mistakes to fix this month

If you have not thought about detectors in a while, start with these:

• Expired alarms still mounted because they look normal
• Battery-only alarms with missing or dead batteries
• No CO alarm in a gas-heated property
• Plug-in CO alarms placed behind furniture where nobody can hear them
• Smoke alarms too close to kitchens or bathrooms, creating nuisance alarms
• No alarm in a finished basement or attic used as living space
• Hardwired alarms disconnected because one unit was chirping
• No written record of the last test

You do not need a complex program to improve. Walk the property, replace bad devices, document the result, and put the next check on the calendar.

You might also like:

• Annual rental inspection checklist for small landlords
• Move-in condition reports: the rental habit that makes deposit decisions easier
• Rental property records: how long to keep

ManorKeeper can help keep the record from disappearing

Smoke and CO detector maintenance is mostly calendar discipline and documentation. ManorKeeper gives small landlords one place to keep property records, maintenance notes, lease details, and turnover tasks together. See how it works.