Where are smoke alarms required in a house in Ontario?
Smoke alarms are required on every storey including the basement, inside each bedroom, and in every hallway serving bedrooms. In new construction they must be hardwired, interconnected, and equipped with battery backup.
Paraphrased for clarity — open this provision in the BUILDAiD Library for the exact wording.
The in-bedroom requirement plus interconnection means a typical two-storey, three-bedroom house needs five or more alarms, all wired so activating one sounds all. Renovations that require a permit commonly trigger upgrading alarms to current requirements, and Ontario's Fire Code independently obliges owners, including landlords, to maintain working alarms in existing homes. Locate alarms away from kitchens and bathrooms to limit nuisance trips, or use photoelectric or hush-feature models. Combination smoke/CO units are a practical way to satisfy both requirements near bedrooms.
New homes need a smoke alarm on every floor, one inside every bedroom, and one in the hallway outside bedrooms, all wired together with battery backup so when one sounds, they all do.
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This page is provided for general information. Building code requirements depend on your specific project, occupancy and municipality, and code editions change. Always verify requirements against the current Ontario Building Code and confirm with your local building department.