Placement & Code
Rental and Landlord Requirements
Rental obligations are usually stricter than the building code, enforced by a different authority, and documented in a different place. Here is how to find out what actually applies to you.
By Ryder M.Last reviewed

For a rental, the national standard is the floor and rarely the whole answer. Landlord duties on smoke and CO alarms come from state landlord-tenant law, local rental licensing or housing codes, and the lease — and those typically add requirements the building code does not: alarms working at the start of every tenancy, written records, response timeframes for repairs, and sometimes sealed ten-year units so batteries cannot be removed. This page tells you where to look and what to ask, not what your specific jurisdiction requires, because that genuinely varies.
No picks here, because the right product for a rental is determined by what the local requirement says — very often a sealed ten-year unit specifically, so that batteries cannot be removed between tenancies. The roundups are linked once you know which type you need.
Why the code is not the answer on its own
NFPA 72 and the residential code tell you where alarms go in a dwelling. They do not tell you who is responsible for them in a tenancy, how often they must be checked, what has to be documented, or what happens when a tenant reports a fault. Those questions are answered somewhere else, and for a rental they are often the questions that matter.
There are usually three or four layers stacked on top of the building code:
State landlord-tenant law. Most states impose duties on landlords about working smoke alarms, and many also cover CO alarms. These commonly specify that alarms must be operational at the start of a tenancy, and allocate responsibility for batteries and testing during it.
Local rental licensing or housing code. Many cities require a license or a periodic inspection for rental property, and the inspection checklist is where the real, enforceable detail lives. It is frequently stricter than the building code — sealed ten-year units, alarms in additional positions, documented testing.
The lease. A lease can allocate duties between landlord and tenant, within the limits state law allows. It cannot generally sign away a statutory landlord duty, but it can put testing and battery replacement on the tenant.
Fire department ordinances, in some jurisdictions, particularly for multi-unit buildings.
What rental rules commonly add
These are patterns that recur across jurisdictions. None of them are universal — treat them as the questions to ask rather than the answers.
Sealed ten-year alarms. An increasingly common requirement, and the reason is straightforward: a sealed battery cannot be removed, which is the commonest way a rental alarm stops working. Where this is required, replacing a nine-volt unit with another nine-volt unit is a compliance failure as well as a bad idea.
Operational at the start of every tenancy, evidenced, with the alarm count and locations recorded at move-in.
Written records of testing and replacement, kept for a specified period. This is the item landlords most often fail on, and it is the cheapest to fix.
A defined response time for a reported fault, often much shorter than for ordinary repairs.
CO alarms where there is any fuel-burning appliance, fireplace or attached garage, sometimes with positions specified more tightly than the building code does.
Tenant duties, typically: test monthly, replace batteries in non-sealed units, report faults promptly, and never disable an alarm. A tenant who removes a battery may be liable, and a tenant who reported a fault in writing usually is not.
If you are a landlord, do this
An hour of work that protects tenants first and you second. The documentation is the part that gets skipped and the part that matters in a dispute.
Call the local rental licensing or housing office
Ask for the alarm requirements on their inspection checklist, and which edition of the building code is adopted. Ask specifically whether sealed ten-year units are required — the answer changes what you buy.
Look up your state's landlord-tenant statute on alarms
Most states publish a plain-language tenant-rights guide that summarizes this. It tells you what you cannot allocate to the tenant.
Audit the unit against the requirement, not against memory
Count sleeping rooms, sleeping areas and levels, and check the exclusion distances. The checklist is designed for exactly this walk-through.
Read the manufacture date on every alarm
Not the install date. Anything over ten years old is a replacement. Between tenancies is the cheapest moment to do it.
Fit sealed ten-year units unless there is a reason not to
Even where they are not required. They remove the single commonest failure mode — a removed battery — for the entire tenancy, and they remove the argument about who was supposed to change it.
Document it, and have the tenant sign
A move-in sheet listing every alarm, its location, its manufacture date and a confirmation that it was tested in the tenant's presence. Photograph each one in place. This is the record that resolves disputes.
Give the tenant the instructions in writing
How to test, what the low-battery and end-of-life signals sound like, who to call and how quickly you will respond. The chirping guide is a reasonable thing to link them to.
Put the re-check in your calendar
Annually, and at every tenancy change. Put the alarm manufacture dates in the same place as the boiler service date.
If you are a tenant, do this
You have more standing here than most tenants realize, and the written record is what gives it to you.
Count and test on day one
One alarm in each bedroom, one outside each sleeping area, one per level including the basement. Press every button. If any of that is missing or silent, you have found it on the day you are in the strongest position.
Read the manufacture dates
On the back of each unit. Over ten years old is not a working alarm, whatever it does when you press the button.
Report anything wrong in writing
Email or text, not a conversation. Describe the unit and its location. This is the single most useful thing a tenant can do, and it is what makes the obligation enforceable.
Never remove a battery or disable an alarm
If an alarm nuisance-trips, report it as a fault — it is usually a placement problem the landlord should fix. Disabling it can make you liable and it removes your protection. Why alarms false-alarm.
Escalate to the local authority if it is not fixed
Your local housing, code enforcement or fire department handles this, and they take alarm complaints seriously. Rental licensing offices in particular have a direct lever.
Add what you are allowed to add
You cannot rewire a flat, but you can put a battery CO alarm on a shelf, keep a fire blanket by the hob and an escape ladder in the bedroom. None of that needs permission and all of it moves with you.
What to buy for a rental
Sealed ten-year alarms, wherever the rules permit them. The whole battery argument disappears, along with the chirp that causes tenants to remove batteries in the first place.
Combination smoke and CO units where CO detection is required, because one device in one position is one thing to document and one thing to replace. The combination alarm roundup.
Nuisance-resistant units for kitchen-adjacent positions. In a rental you cannot rely on a tenant tolerating a badly-behaved alarm, and a unit listed to UL 217 8th edition for cooking-nuisance resistance is the difference between an alarm that stays connected and one that does not. Kitchen placement.
Wireless interconnect where the building has no alarm wiring. It is the cheapest way to get whole-unit alerting into an older property without opening walls. Interconnected smoke alarms.
And if the property has a basement bedroom, check the escape opening before anything else. Basement window well escape covers what the requirement asks for, and a non-compliant basement bedroom is a serious problem in a let.
Questions people actually ask
Who is responsible for smoke alarms in a rental?
How many smoke detectors does a rental need?
Can a landlord require a tenant to replace smoke alarm batteries?
What can a tenant do if the landlord will not fix a smoke alarm?
Do short-term rentals need smoke alarms?
Are sealed 10-year alarms required in rentals?
Sources
- NFPA — NFPA 72, National Fire Alarm and Signaling Code (2025 edition)
- International Code Council — IRC Chapter 3 — building planning (R310, R314, R315)
- NFPA — Smoke Alarms in US Home Fires
- CPSC — Carbon Monoxide Fact Sheet
Read next

Placement & Code
How Many Smoke Detectors Do I Need?
Worked counts for real house shapes, including split levels and open plans.

Placement & Code
NFPA 72 Residential Requirements
The residential sections, quoted with their numbers, and what each one means in practice.

Smoke Detectors
The Best Combination Smoke and CO Alarms
Two listings, one position — and the one room where separate units win.

Smoke Detectors
Interconnected Smoke Alarms
Why interconnection matters most, and the wired, wireless and hybrid routes.

Placement & Code
Home Fire Safety Checklist
A printable room-by-room audit of alarms, CO detection, exits and suppression.