National baseline
The NBC Part 9 sets the fire-resistance rating for the garage-to-dwelling separation, door requirements, and vapour barrier provisions.
Canadian building code question
What are the building code requirements for fire separation between a garage and house in Canada?
An attached garage must be separated from the dwelling by a fire separation with a minimum fire-resistance rating. The code also requires a self-closing door between the garage and the dwelling and a continuous vapour barrier or air seal to prevent exhaust gas migration.
The fire separation between an attached garage and the living space is one of the most commonly inspected residential code requirements. It protects occupants from fire spread, exhaust gas migration, and carbon monoxide exposure. Getting the assembly rating, door specification, and vapour barrier details right prevents failed inspections and safety risks.
What to check first
- The garage-to-dwelling separation must have a minimum fire-resistance rating as specified by the applicable code.
- Doors between the garage and dwelling must be self-closing and meet the required fire-protection rating.
- A continuous vapour barrier or air seal is required to prevent exhaust gas and carbon monoxide migration into the dwelling.
Jurisdiction notes
Province and edition check
Provincial codes may amend the required fire-resistance rating or add specific requirements for garage door hardware. Verify the adopted edition.
Overhead conditions
When the dwelling has habitable space above the garage, the ceiling assembly fire-resistance rating and any structural fire-protection requirements also apply.
Work through it in this order
- Confirm whether the garage is attached to or part of the dwelling and identify all shared walls, ceilings, and floors.
- Verify the required fire-resistance rating for each element of the garage-to-dwelling separation.
- Specify a self-closing door with the required fire-protection rating for any door openings between the garage and the dwelling.
- Confirm the vapour barrier or air seal requirements to prevent exhaust gas migration.
- Review any additional requirements for habitable space above the garage.
- Document the assembly details and confirm with the local building department.
Common questions
What fire-resistance rating is required between a garage and house?
The NBC specifies a minimum fire-resistance rating for the garage-to-dwelling separation. The specific rating depends on the code edition and provincial adoption.
Does the door between the garage and house need to be fire-rated?
The door must be self-closing and meet a minimum fire-protection rating. The specific rating and hardware requirements depend on the applicable code.
Do I need a vapour barrier between the garage and the house?
Yes. A continuous vapour barrier or air seal is required to prevent exhaust gas and carbon monoxide migration into the dwelling.