Ontario CO2 Rules

Ontario’s New CO Alarm Rules for 2026: What Every Homeowner Needs to Know

Carbon monoxide (CO) remains one of the most dangerous hazards in Canadian homes — invisible, odourless, and capable of becoming deadly within minutes. Ontario has updated its safety regulations to strengthen protection for residents, and new CO alarm placement rules take effect on January 1, 2026.

Whether you’re a homeowner, landlord, or property manager, these changes affect you. Here’s a clear breakdown of what’s new, why it matters, and how to get your home compliant.

Why Ontario Updated the CO Alarm Rules

Carbon monoxide incidents continue to be a leading cause of preventable home fatalities. Many homes still lack working alarms, and inspections across the province have shown inconsistent installation practices.

The updated rules aim to:

• Improve early detection

• Reduce preventable injuries and deaths

• Standardize alarm placement across all home types

• Ensure better protection for sleeping occupants

What’s Changing in 2026

Beginning January 1, 2026, the Ontario Fire Code requires:

1. CO Alarms on Every Level of the Home

If your home has any of the following, you must install CO alarms on every storey:

• Gas furnace

• Gas or wood fireplace

• Gas stove or oven

• Gas water heater

• Fuel‑burning boiler

• Attached garage

• Any other fuel‑burning appliance

This is a major expansion from the previous rule, which required alarms only near sleeping areas.

2. CO Alarms Still Required Near Sleeping Areas

Even with the new “every level” rule, alarms must still be placed:

• Adjacent to each sleeping room

• Inside any bedroom containing a fuel‑burning appliance

3. Additional Requirements from the Ontario Building Code

For new builds and major renovations, CO alarms must also be installed:

• On every storey without a sleeping room

• In service rooms containing fuel‑burning appliances

• In suites sharing a wall, floor, or ceiling with a garage

Technical Standards

CO alarms must be:

• Hard‑wired (no disconnect switch)

• Equipped with battery backup

• Capable of visual signaling

• Certified to CAN/CSA‑6.19 or UL 2034

Final Thoughts

Ontario’s updated CO alarm rules are designed to save lives — and compliance is straightforward once you know where alarms must go. Installing alarms on every level, especially near sleeping areas and fuel‑burning appliances, ensures your home is protected long before the 2026 deadline.