Carbon Monoxide Alarm Requirements: 2026 Landlord Guide
Ontario Fire Code enforcement is tightening for 2026. Ensure your rental properties meet strict carbon monoxide alarm placement and testing standards to avoid fines.
The "Silent Killer" and Your Legal Duty
Carbon monoxide (CO) is an odorless, colorless, and tasteless gas that can cause illness and death. As a landlord in Ontario, ensuring your tenants are protected from CO is not just a moral obligation—it is a strict legal requirement under the Ontario Fire Code.
For 2026, fire departments across Ontario are emphasizing "zero tolerance" enforcement programs. Landlords found without working alarms during inspections or after responding to complaints can face immediate tickets or summonses.
Who Needs a CO Alarm?
You must install CO alarms in any residential unit that contains:
- A fuel-burning appliance (furnace, water heater, gas stove, gas dryer, fireplace, portable heater)
- OR an attached garage (parking below or beside the unit)
If your property is all-electric (electric baseboards + electric stove/water heater) and has no attached garage, you technically may not require a CO alarm under the Fire Code, but installing one is still highly recommended for liability protection.
Where to Install Alarms
Proper placement is critical for compliance:
- Adjacent to Sleeping Areas: This generally means in the hallway outside bedrooms. The alarm must be audible inside the bedroom when the door is closed.
- Every Level (House Policy): While the strict minimum is "adjacent to sleeping areas," many municipalities and best practices suggest one on every level of the home.
- Service Rooms: In multi-unit buildings, CO alarms may also be required in service rooms containing fuel-burning appliances.
Check Expiry Dates
CO sensors degrade over time. Alarms typically expire after 7 or 10 years. Inspect every unit in your properties: turn them over and check the date of manufacture. Replace any that are expired immediately. An expired alarm = no alarm in the eyes of the law.
Maintenance Obligations
Landlord Responsibilities:
- Installing the alarms
- Testing alarms annually (keep a log!)
- Testing alarms when a new tenancy begins
- Replacing batteries as needed
- Replacing the unit when it expires or malfunctions
- Providing manufacturer instructions to tenants
Tenant Responsibilities:
- Notifying the landlord if the alarm is not working
- Not tampering with or disabling the alarm
Testing Tip
When you perform your annual smoke/CO alarm test, have the tenant sign a document confirming the test was done and the alarm was working. This "maintenance log" is your primary defense against negligence claims.
Testing Checklist for 2026
To ensure complete compliance this year:
1. Inventory Check
List every unit and note the type (hardwired/battery) and expiry date of every CO alarm.
2. Perform Annual Test
Press the "Test" button on every unit. Ensure it sounds clearly. Vacuum dust from the sensor vents.
3. Replace Old Batteries
For battery-operated units, install fresh batteries annually (e.g., at daylight savings time) unless they are 10-year sealed units.
4. Document Everything
Record the date, time, unit number, specific alarm tested, and result. Keep this log permanently.
5. Educate Tenants
Remind tenants that disabling alarms is a provincial offense. Provide a simple handout on what to do if the alarm sounds (Evacuate -> Call 911).
Types of Alarms
Sound Only: Standard alarms that beep loudy. Acceptable for most regular tenancies.
Visual & Sound (Strobe): If you have tenants who are deaf or hard of hearing, you have a duty to accommodate them by installing visual strobe alarms.
Combination (Smoke + CO): These are convenient but verify the expiry dates carefully—sometimes the CO sensor expires before the smoke sensor.
Frequently Asked Questions
Related Resources
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