Canadian building code question

What is the required width of an exit door in Canada?

The required exit door width depends on the door's function in the egress system, the occupant load it must serve, barrier-free access requirements, and how the province adopts or amends the means-of-egress provisions. A general minimum applies, but higher occupant loads and accessibility provisions can increase the requirement.

Exit door width is often treated as a fixed number, but the actual requirement can change with the door's egress role, the occupant load, whether barrier-free access applies, door hardware and swing conditions, and provincial adoption. The safest approach is to confirm the door's function and the occupant load first, then verify the cited width provision for the applicable code edition.

What to check first

  • Identify the door's egress function — exit door, suite entrance door, or access-to-exit door — because the applicable width provision can differ.
  • Check the occupant load the door must serve, since higher occupant loads can require a wider door than the general minimum.
  • Verify barrier-free access requirements and provincial amendments, as both can set a wider minimum or add hardware and clearance conditions.

Jurisdiction notes

National baseline

Start with the NBC means-of-egress provisions for exit door width, including the general minimum and any occupant-load-based capacity requirements.

Province and edition check

Confirm whether the province amends the exit door width provisions or adopts a code edition with different requirements for specific building types.

Project-specific variables

Door function, occupant load, barrier-free access, door hardware, swing direction, and vestibule conditions can all change the required width.

Work through it in this order

  1. Identify the door's function in the egress system and the occupant load it must serve.
  2. Review the NBC exit door width provisions for the general minimum and any occupant-load-based requirements.
  3. Check barrier-free access provisions for additional width, hardware, and clearance requirements.
  4. Verify provincial adoption and confirm that the door hardware, swing, and clear-opening conditions do not reduce the usable width below the requirement.

Common questions

Is the exit door width the same for every building?

No. The required width depends on the door's egress role, the occupant load, barrier-free access requirements, and provincial adoption.

Does the barrier-free door width requirement apply to all exit doors?

Barrier-free width requirements apply to doors on the barrier-free path of travel. Not every exit door may be on that path, but when it is, the barrier-free clear-opening requirement must be met.

How is door width measured — frame opening or clear opening?

The code typically specifies clear opening or clear width, which accounts for the door leaf, hardware, and any projections. Verify the cited measurement method for the applicable provision.