Smoke and carbon monoxide detector rules for NYC rentals
NYC landlords must install smoke and CO detectors in every apartment; tenants test and maintain them. What you can be charged, placement rules and reporting.
7 min read · Updated
In NYC, the landlord must supply and install at least one working smoke detector and, in buildings with gas, oil or other fuel-burning equipment, at least one carbon monoxide (CO) detector in every apartment. Once they are in, you are responsible for testing them, changing batteries and replacing a detector that is stolen, removed, missing or made inoperable while you live there.
The rules come from the city's Housing Maintenance Code and are enforced by HPD. Below: where detectors must go, who pays, when the owner must replace one, and what to do if your apartment has none.
At a glance
- Who installs
- The owner
- At least one smoke and one CO detector per apartment
- Where
- Within 15 feet of each bedroom door
- For both smoke and CO detectors
- Tenant cost (Class A building)
- Up to $25 per detector
- $50 or $75 for combination units
- Time to repay
- 1 year
- From installation
- Missing detector violation
- Class B
- Hazardous
- Testing
- Tenant, at least monthly
- Batteries at least twice a year
Which detectors your apartment needs
- Smoke detectors. Owners of Class A multiple dwellings (ordinary apartment buildings with three or more units) and Class B multiple dwellings (transient housing such as hotels and rooming houses) must provide and install at least one approved, working smoke detector in each apartment.
- Carbon monoxide detectors. Required in every apartment of a building that has a fossil fuel burning device, such as a gas or oil boiler, gas stove or gas water heater. The rule also covers one- and two-family homes that the owner does not occupy.
- Natural gas detectors. A newer requirement for multiple dwellings and non-owner-occupied one- and two-family homes with gas piping, installed under the NYC Building Code where the gas-burning appliance is located. HPD's page does not give a firm compliance date, so check it for the latest.
A single combination device can count for more than one requirement if it is installed where each type must be. Every detector must have an end-of-life alarm.
Where they must be placed
In a Class A building, smoke and CO detectors must be within 15 feet of the primary entrance to each room lawfully used for sleeping. In a rented one- or two-family home the same 15-foot rule applies to CO detectors. If your bedrooms are far apart, one detector may not be within 15 feet of every bedroom door, so you may need more than one.
Who pays for the detectors
The owner can pass part of the cost of a newly installed detector to the tenant in some buildings, within strict limits:
| Building type | Smoke, CO or gas (single) | Two-in-one combo | Smoke + CO + gas combo |
|---|---|---|---|
| Class A multiple dwelling (typical apartment building) | $25 | $50 | $75 |
| Class B multiple dwelling (hotel, rooming house) | $0 | $0 | $0 |
| Rented one- or two-family home | $25 (CO or gas) | - | - |
The charge applies to a newly installed detector, or one the owner had to install because the tenant failed to maintain, lost or damaged the old one. You have one year from installation to pay. A landlord who bills more than these amounts, or bills for a detector already in the apartment when you moved in, is outside the rule as HPD describes it.
Owner vs. tenant: who does what
| Owner | Tenant | |
|---|---|---|
| Buy and install the first detectors | ||
| Give a written notice on testing, maintenance and CO poisoning | ||
| Post a detector notice in the building entrance area | ||
| Test every detector at least once a month | ||
| Change batteries at least twice a year, and when it chirps | ||
| Replace a detector stolen, removed or broken during your tenancy | ||
| Replace a detector that fails within 1 year from a defect | Within 30 days | |
| Replace detectors at the end of their useful life | ||
| Replace a missing or broken detector before a new tenant moves in | ||
| Keep records of install dates and expiration dates |
If your apartment has no working detector
- 1
Check if it is a battery or end-of-life problem
A chirp usually means a low battery. Replace it with the recommended type. If the end-of-life alarm sounds, the detector has expired and the owner must replace it. - 2
Write to the landlord
If there is no detector, or it is defective or expired, ask the owner in writing to install or replace it. Note the date. - 3
File a 311 complaint
Use 311 Online, the app or call 311. HPD inspectors check for working smoke and CO detectors at every complaint inspection, whatever the complaint is about. See how to file an HPD complaint. - 4
Protect yourself in the meantime
A plug-in or battery CO alarm and a battery smoke alarm are inexpensive. Installing your own does not cancel the owner's duty.
What HPD issues
A missing or defective smoke or CO detector is written as a Class B (hazardous) violation. A missing CO notice in the building is usually a Class A violation.
| Violation | Class | Violations |
|---|---|---|
| Repair, replace or provide a carbon monoxide detecting device | B | 31,184 |
| Repair, replace or provide a smoke detecting device | B | 27,973 |
That is close to 60,000 detector violations in a year, making them some of the most common hazards HPD writes. Look up any building on Roofy's building lookup to see its open violations.
When an alarm goes off
- Smoke alarm: get out and call 911 from outside.
- CO alarm: HPD notes CO is odorless and highly toxic. Get everyone out to fresh air and call 911.
- Gas smell: leave, then call 911 and the utility from outside. More in no cooking gas in your building.
Owners: the full checklist of notices, records and filing duties is in NYC smoke and CO detector rules for landlords. This guide is general information, not legal advice; HPD's detectors page is the official source.
Independent fact-check 2026-10-12. HPD detectors page re-read: smoke detectors in Class A and B multiple dwellings; CO detectors also in non-owner-occupied 1-2 family homes with fossil fuel devices; natural gas detectors per Building Code (no firm date given); 15-foot placement; end-of-life alarm; owner replaces at end of life, before new tenant, and within 30 days for defect in first year; notices, posting and records; charges of $25/$50/$75 (Class A), none in Class B, $25 per CO or gas detector in 1-2 family homes, one year to pay; tenant monthly testing, twice-yearly batteries, never paint over; CO exemptions. MDL §4 Class A/B definitions read on nysenate.gov. HPD ABCs of Housing confirms HPD always checks smoke and CO detectors at complaint inspections. Re-ran wvxf-dwi5 (inspection dates Oct 1, 2025 to Sep 30, 2026): smoke device B 27,973, CO device B 31,184 match; CO notice violations confirmed Class A (3,123). Removed an unsourced hallway-placement inference and unsourced fire-escape advice.
Sources
- Smoke, Carbon Monoxide, and Natural Gas Detectors · NYC HPD (accessed October 12, 2026)
- Sample notice: smoke detecting devices · NYC HPD (accessed October 12, 2026)
- Multiple Dwelling Law §4: Definitions (Class A and Class B) · New York State Senate (accessed October 12, 2026)
- ABCs of Housing (2021) · NYC HPD (accessed October 12, 2026)
- Housing Maintenance Code Violations (open data) · NYC Open Data (accessed October 12, 2026)
General information, not legal, tax or financial advice. Rules change; confirm with the agency or a professional before you act.