Canadian building code question

What is the minimum number of washrooms required in a building in Canada?

The minimum number of washrooms depends on the building's occupancy classification, the occupant load, sex-based fixture ratios where applicable, and how the province splits washroom requirements between the building code and plumbing code. There is no single national count that applies to every building.

Washroom counts are driven by occupancy, occupant load, and fixture-count tables that can sit in the building code, the plumbing code, or both, depending on the jurisdiction. The calculation also depends on whether the building has multiple occupancies, whether barrier-free washrooms are required, and how the province adopts the relevant standards. The safest workflow is to confirm the occupancy and occupant load first, then verify the fixture-count path for the applicable jurisdiction.

What to check first

  • Start with the occupancy classification and calculated occupant load, because fixture-count tables use these as primary inputs.
  • Check whether the province handles washroom counts through the building code, the plumbing code, or a combination, since this affects where you find the governing table.
  • Account for barrier-free washroom requirements and sex-based fixture ratios, which can increase the total count beyond the base occupant-load calculation.

Jurisdiction notes

National baseline

The NBC and the National Plumbing Code both contain provisions that can affect washroom and fixture counts. Confirm which code path applies before calculating.

Province and plumbing code check

Some provinces adopt plumbing code fixture tables separately from the building code. Verify whether the washroom count is governed by the building code, the plumbing code, or both.

Project-specific variables

Occupancy, occupant load, mixed-use conditions, sex-based ratios, barrier-free washroom obligations, and tenant planning can all change the required washroom count.

Work through it in this order

  1. Confirm the occupancy classification and calculate the occupant load for each use area in the building.
  2. Identify whether the province's washroom count requirement is in the building code, the plumbing code, or both.
  3. Apply the applicable fixture-count table using the occupant load and occupancy classification as inputs.
  4. Add barrier-free washroom requirements and verify that the total count meets all cited provisions before the layout is finalized.

Common questions

Is the washroom count the same for every building type?

No. Office, retail, assembly, industrial, and residential buildings typically have different fixture-count requirements based on their occupancy and expected occupant load.

Where do I find the fixture-count table?

Depending on the province, it may be in the building code, the plumbing code, or both. Verify the applicable code path for the jurisdiction before relying on a single source.

Do barrier-free washrooms count toward the total?

Generally yes, but the requirement to provide barrier-free washrooms may add to the total count or require specific configurations beyond what the base fixture-count table alone requires.