If you’re thinking about tearing down a detached garage, backyard shed, or an old extension on your home, you’re not alone. Montreal homeowners often run into the same question: Do I need a permit for this? Can I do it myself? Let’s break down the legal, structural, and logistical aspects of garage demolition in Montreal — what you can do, what you can’t, and what happens if you get it wrong.
⛏️ Do I Need a Permit to Demolish a Garage in Montreal?
In most boroughs of Montreal, yes — any structure larger than 10 m² (about 107 ft²) requires a permit for demolition. This includes detached garages, large sheds, and home extensions like sunrooms or rear additions.
You can view the city’s official page on how to get a demolition permit for more details.
You Don’t Need a Permit If:
- The structure is under 10 m² and not attached to your home
- There are no plumbing, electrical, or gas lines involved
- You’re not altering the foundation or shared wall
You Absolutely Need a Permit If:
- The structure is attached to the home or connected to utilities
- The building is over 10 m² in size
- You live in a heritage-protected zone
What About Sheds?
Sheds under the size limit usually don’t require permits, but you still need to ensure it’s not infringing on zoning setbacks or bylaws. Use caution when removing anything that has a base anchored to concrete or involves wiring.
Visit our demolition services page to learn how we handle small-scale structures.
Can You Demolish a Garage Yourself in Montreal?
Technically, yes — but it comes with serious caveats.
DIY Is Possible IF:
- You’re confident in your structural understanding
- You’re prepared to safely handle roof teardown
- You arrange for licensed disposal (dumping rules apply)
- No asbestos or hazardous materials are involved
⚠️ Warning: DIY garage demolition in Montreal may void your home insurance if damage occurs. Always notify your insurer before beginning work.
What Happens If You Demolish Without a Permit?
Penalties vary by borough, but most fines start at $500 and can exceed $2,000 — plus mandatory reconstruction costs if inspectors intervene. DemoPrep has assisted homeowners facing these issues before. The city doesn’t play around with unpermitted demo, especially in high-density neighborhoods.
What a Pro Demolition Team Like DemoPrep Does Differently
If you’re considering garage demolition in Montreal, here’s what working with DemoPrep looks like:
- We file and manage your permits – No guesswork
- We cap or relocate utilities safely and legally
- We bring licensed asbestos testing if needed
- We dispose of all debris at authorized facilities
Want to see how we handle projects from garage removal to full additions? Check our latest projects for real examples.
Extensions: The Legal Gray Zone
Extensions are the trickiest structures to demolish. Some are classified as permanent additions. Others are treated as exterior structures. The rule of thumb is: if it shares a foundation with the main home, it counts as structural.
That means full permits, engineer oversight, and often zoning checks are needed before any wall comes down. Want to add a new one later? Learn about renovation planning with our team.
Demolition Planning Checklist (Montreal-Specific)
| Structure | Permit Needed? | DIY Safe? |
|---|---|---|
| Detached Shed < 10 m² | No | Yes |
| Detached Garage | Yes | Maybe |
| Attached Garage | Yes | No |
| Extension w/ foundation | Yes | No |
Don’t Forget Waste Disposal Rules
Montreal has strict policies about construction waste. You can’t just throw old lumber and shingles into your regular bin. DemoPrep handles transportation, sorting, and disposal to ensure compliance with city recycling and landfill rules.
️ Final Thoughts
Whether you’re dealing with a collapsing garage, an aging shed, or a weird extension built in the ’80s, demolition isn’t just a swing of a hammer. Montreal’s rules are strict. The risk of mistakes is high. And the cost of doing it wrong is always more than doing it right.
Need help with garage demolition in Montreal? Contact DemoPrep today for a quote — we’ll walk you through what’s legal, what’s possible, and what it’ll cost.
