Smoke and carbon monoxide detectors aren’t just suggestions — they’re legal requirements in Quebec. Here’s exactly what the law requires, where to install them, and who’s responsible.
Two protections, two obligations
The smoke detector is mandatory in every dwelling. The carbon monoxide (CO) detector is too, as soon as there’s a combustion appliance or an attached garage. Both save lives every year — and their absence can cost dearly in a claim.
Where and how many
🔥 Smoke detector
Mandatory in every dwelling: at least one per floor, including the basement, and near the bedrooms. One on each living level.
🫧 CO detector
Mandatory since April 1, 2019 if your home has a combustion appliance (stove, fireplace, gas/oil water heater or furnace) or is adjacent to a garage. Install one on each floor with a bedroom.
Hardwired and interconnected
In recent construction, detectors are wired to 120 V with a backup battery and interconnected: if one sounds, they all sound. It’s the best protection — smoke in the basement wakes everyone upstairs. An existing home can also be upgraded to this type of system.
Where to place them exactly
- Smoke: on each floor, near bedrooms (ideally in the hallway), and inside bedrooms for deep sleepers. On the ceiling, since smoke rises.
- Avoid: too close to the kitchen, bathroom or a fan — false alarms discourage people and lead to unplugging (never do that).
- Carbon monoxide: on each floor with a bedroom, at the height recommended by the manufacturer, and near combustion appliances.
Photoelectric, ionization, combined
Photoelectric
Excellent for smouldering fires (that smoke for a long time before flaming). Recommended for the home.
Ionization
Reacts fast to flaming fires. Some units combine both technologies.
Combined smoke + CO
One device for both dangers: convenient, fewer units to manage, very popular.
Tenant or owner?
The owner must provide compliant alarms and see to their installation. The tenant must maintain them, check that they work, and replace batteries as needed (and notify the owner of a faulty unit).
Is your home compliant?
We check, install and interconnect your detectors by the book. Free quote.
Your questions about detectors
How many smoke detectors do I need?+
At least one per floor, including the basement, and near the bedrooms. That’s the minimum required in every Quebec dwelling.
When is a CO detector mandatory?+
Since April 1, 2019, as soon as there’s a combustion appliance (stove, fireplace, gas/oil water heater or furnace) or an attached garage. Install one on each floor with a bedroom.
Who is responsible, tenant or owner?+
The owner provides and installs compliant alarms; the tenant maintains, tests and replaces batteries as needed.
Should detectors be hardwired?+
It’s the best protection: wired with a backup battery and interconnected, they all sound together. Recommended, and often required in new construction.
How often should I replace them?+
Test each month, change batteries yearly, and replace the whole unit about every 10 years.
My detector sounds for no reason — why?+
Often from dust, cooking or shower steam, a low battery, or end of life (10 years). Clean it, change the battery — if it persists, replace it. Never unplug it.
Are combined smoke + CO detectors a good idea?+
Yes, very convenient: one device covers both dangers. Make sure it’s certified and well placed for both functions.
Where should I place the CO detector?+
On each floor with a bedroom, near sleeping areas and combustion appliances, at the height recommended by the manufacturer.
