Thinking of opening up your floor plan, removing a load-bearing wall, or expanding a room? When it comes to structural modifications in Montreal, the line between what a contractor can do and what legally requires an engineer is critical. Getting this wrong can result in major safety risks, denied permits, or costly delays.
This guide breaks down exactly who you need—and when—to stay compliant and safe during your renovation project in Montreal.
What Counts as a Structural Modification?
Structural modifications involve any change to the framework or load-bearing elements of a building. These can include:
- Removing or altering load-bearing walls
- Modifying beams, columns, or floor joists
- Cutting into foundation walls or slabs
- Changing the roofline or dormer additions
- Expanding windows or doors in exterior walls
These aren’t cosmetic changes—they directly affect the safety and stability of the home. That’s why the City of Montreal has specific requirements around permits and structural oversight. Learn about permits here.
️ Engineer vs. Contractor: Who Does What?
| Task | Engineer | Contractor |
|---|---|---|
| Assess load-bearing walls | ✅ Required | ❌ Not authorized |
| Design new structural beams or supports | ✅ Required | ❌ |
| Submit stamped structural drawings for permits | ✅ | ❌ |
| Execute physical demolition or installation | ❌ | ✅ |
| Handle non-structural reno (drywall, cabinets) | ❌ | ✅ |
In short: if a wall supports anything above it—roof, floor, another wall—it requires an engineer’s plan before demo or modification can begin.
Montreal-Specific Requirements
Montreal’s RBQ and municipal building codes are clear: structural changes must be reviewed and approved by a licensed engineer. In fact, permit submissions for structural work must include an engineer’s stamped drawings and load calculations.
For example:
- Removing a wall between your kitchen and living room? You’ll need an engineer to specify the replacement beam.
- Expanding a basement window to meet egress codes? Structural analysis is required to support the surrounding foundation.
DemoPrep works directly with engineers to ensure your project meets code—and gets approved the first time.
FAQ: Montreal Homeowners Ask Us This All the Time
- Do I always need an engineer to remove a wall?
- If it’s structural—yes. If it’s purely decorative or partition-based, no.
- How much does structural engineering cost in Montreal?
- Expect $1,200–$2,500+ for stamped drawings and site inspection, depending on complexity.
- Can DemoPrep handle both demolition and coordination with the engineer?
- Yes. We provide a full-service package that includes demo, permits, and build-back coordination.
The Risks of Skipping the Engineer
- ❌ Denied permits or stop-work orders
- ❌ Insurance issues if damage occurs
- ❌ Safety concerns for your family
- ❌ Costly retrofits later on
Don’t treat an open-concept renovation like a DIY project. It’s not worth the gamble—especially with load-bearing walls or foundation changes.
How DemoPrep Handles Structural Modifications in Montreal
- Free site assessment to evaluate what’s structural
- Partnership with certified engineers for stamped drawings
- Submission and handling of city permits
- Safe demolition using licensed and insured crews
- Optional rebuild or renovation phase coordination
Every step of our process is designed to avoid surprises, delays, or compliance issues.
Thinking of Structural Changes? Start With a Site Visit
If you’re considering any structural modifications in Montreal, contact DemoPrep first. We’ll give you clear guidance, connect you with the right professionals, and ensure your project stays safe and compliant.
Book your consultation today →
