Canada · Fire protection

What are the building code requirements for demising walls in Canada?

Demising wall requirements depend on the occupancies on each side of the wall, the fire separation rating required between suites or tenancies, sound transmission class requirements, structural support conditions, and how the province adopts or amends the national model code.

Demising walls sit at the intersection of fire safety, acoustics, and occupancy separation. The required fire-resistance rating, sound transmission class, and construction details can all change depending on what is on each side of the wall and how the province interprets the NBC provisions. Confirming the occupancy pair and the applicable separation requirements is the safest starting point.

What to check first

  • Identify the occupancies on each side of the wall because fire separation and STC requirements are driven by the occupancy pair.
  • Check fire separation requirements between suites, tenancies, or occupancies as these set the minimum fire-resistance rating for the wall.
  • Verify sound transmission class (STC) requirements where residential or sleeping occupancies are involved.

Jurisdiction notes

National baseline

Start with the NBC fire separation tables and sound transmission requirements that apply to walls between suites and occupancies.

Province and edition check

Confirm how the province adopts the NBC provisions and whether additional STC or fire separation requirements apply.

Project-specific variables

Occupancy classification on each side, suite versus tenancy distinction, residential versus non-residential use, and building height can all change the wall requirements.

Not professional advice

CodeCan reports what the published building code says. It is not legal, engineering, or architectural advice, and it does not certify compliance. Building codes are adopted and amended provincially and enforced locally — always verify with your authority having jurisdiction (AHJ) before you build.

Work through it in this order

  1. Identify the occupancies and uses on each side of the demising wall.
  2. Look up the required fire separation rating for the occupancy pair in the NBC tables.
  3. Check whether STC requirements apply based on the occupancies involved.
  4. Verify provincial adoption and any amendments, then document the cited sections.

Common questions

Is a demising wall always a fire separation?

In most cases yes, because the NBC requires fire separations between suites and between different occupancies. But the specific fire-resistance rating depends on the occupancies involved.

Do demising walls have sound transmission requirements?

They can, particularly when residential or sleeping occupancies are on one or both sides of the wall. The NBC and provincial codes specify minimum STC ratings for these conditions.

Why does the answer depend on the province?

Because provinces adopt the NBC with amendments, and some provinces have different STC requirements or fire separation interpretations for certain building types.