Two multi-family buildings. Same city, same use, one storey apart. One costs roughly what you’d expect per unit. The other costs meaningfully more, per unit, for reasons that have nothing to do with finishes or land price.
The difference is a line in the building code most people never look for until it’s already too late to design around it.
The mistake happens before the drawings
Most people pricing a Winnipeg multi-family project assume cost scales roughly with unit count — more doors, proportionally more cost. That assumption holds right up until a project crosses a specific threshold in the Manitoba Building Code, at which point the entire regulatory and engineering framework changes underneath it.
It is not a gradual increase. It is a step change, and it is set in law, not in anyone’s judgment.
What the rule actually says
Manitoba adopted the National Building Code of Canada 2020 through Manitoba Regulation 78/2023, in force since January 1, 2024. It sets the line between the two regulatory tracks explicitly:
- Part 9 covers residential buildings up to 3 storeys and under 600 square metres in building area
- Part 3 applies the moment a building exceeds either threshold — more than 3 storeys, or more than 600 m², whichever comes first
- The two tracks are not a difference of degree. They are different engineering and code-compliance regimes
Most of Winnipeg’s duplex, triplex, and fourplex infill activity sits comfortably inside Part 9. A five-storey building does not — and the two are not scaled versions of the same project, regulatorily speaking.
Why the line costs real money
Crossing into Part 3 is not a paperwork difference. It generally brings:
- Full structural engineering, typically stamped by a professional engineer, rather than prescriptive Part 9 tables
- Different fire separation and, in most cases, sprinkler requirements
- Elevator and accessibility requirements that don’t apply to a 3-storey walk-up
- A longer, more document-heavy permitting process
None of this shows up on a per-door land comparison. It shows up in the construction budget, and by the time it does, the design is usually too far along to walk back cheaply.
Confirming which code track a project falls under is one of the first things we check on any large multi-family project — before a single drawing is finalized.
"Won’t my project naturally land on one side or the other?"
Not always. Projects that sit close to the line have real design choices available:
- Splitting one large building into two smaller ones can sometimes keep each structure under the area threshold
- Massing and storey count can be adjusted early, when it is cheap to change, rather than late, when it isn’t
- Whether staying in Part 9 is actually the right call depends on the site and the unit count you need — it is not automatically the cheaper path once you account for what you give up
This is a design decision, not a technicality, and it needs to be made before drawings are finalized, not after.
How to check where your project falls
- Calculate total building area in square metres, not just unit count
- Confirm storey count as defined by the code, including any partial or mezzanine levels
- Check both thresholds — area and height — since either one alone can trigger Part 3
- If you’re near the line, model both massing options before committing to drawings
- Confirm with a design-build team that has actually delivered a Part 3 project in Manitoba, not just Part 9 infill
Once design work is underway, changing which code track a project falls under gets expensive fast. Confirming it early is close to free.
Planning a multi-family project in Winnipeg? We’ll tell you which code track it falls under, and what that actually means for your budget, before you commit to a design. Get in touch with Summit
Where Summit fits
We deliver both sides of this line — small multi-family infill under Part 9, and large multi-family projects under Part 3 — through construction management that starts with confirming which regulatory track a project is actually on.
Keep reading
If you are weighing where a project lands on this line, these go deeper:
- Winnipeg Infill Construction: By-Law 59/2025 Costs in 2026 — real cost per door for duplex, triplex and 4-plex builds
- The 800-Metre Transit Height Rule — how lot location changes what you can build