Ontario’s 2026 CO Alarm Changes: What Homeowners Need to Know
As of January 1, 2026, Ontario has updated rules around carbon monoxide (CO) alarms in residential properties. These changes are focused on improving safety by ensuring earlier detection of carbon monoxide, an invisible, odourless gas that can become life-threatening without warning.
CO is produced when fuels such as natural gas, propane, oil, wood, or gasoline do not burn completely. It can come from everyday household sources, such as furnaces, water heaters, fireplaces, and even vehicles in attached garages. Because it cannot be seen or smelled, properly placed CO alarms are essential for protecting everyone in your home.
If your home has any fuel-burning appliance (such as a hot water tank heated by natural gas), a fireplace, an attached garage, or is heated by an external fuel source, you are required by law to have CO alarms.
The New Rule and Where CO Alarms Must Be Installed
If your home meets any of the conditions above, you must install a CO alarm in these two locations:
- Adjacent to each sleeping area (near all bedrooms).
- Effective Jan 1, 2026: On every storey (floor) of your home, including storeys that do not have a sleeping area.
This applies to houses, townhomes, and condos alike.
What Landlords and Tenants Need to Know
Landlords are responsible for:
- Installing CO alarms where required
- Keeping them in working condition
- Testing them annually and between tenancies
- Providing tenants with proper usage and maintenance instructions
Tenants are responsible for:
- Testing alarms regularly (monthly is recommended)
- Report any issues immediately
- Never tamper with or disable the alarm
Why This Matters
Carbon monoxide poisoning remains a leading cause of accidental poisoning in Ontario. The updated rules bring broader protection by ensuring every level of a home is monitored, helping detect rising CO levels sooner and giving occupants more time to respond.
Simple Safety Reminders
- Test CO alarms monthly
- Replace batteries as recommended
- Replace units every 7–10 years (or per manufacturer guidelines)
- Have fuel-burning appliances professionally inspected annually
- If an alarm sounds, get outside immediately and call 9-1-1
Ontario’s expanded CO alarm requirements are a meaningful step toward better home safety. By requiring alarms near sleeping areas and on every level, these updates increase the chances of early detection and faster response. Taking a few minutes to install, test, and maintain your alarms can provide critical protection against a hazard you can’t detect on your own