Do I Need a Permit to Build a Deck in Ontario?
- John Barnhart
- Jul 29
- 2 min read
A backyard deck is one of the most popular home improvement projects in Ontario — but before you start building, there’s one important question you need to ask:
Do I need a permit for my deck?
The answer depends on the size, height, and design of your deck. Skipping the permit could lead to failed inspections, fines, or having to tear it down. This guide will help you understand when a deck permit is required in Ontario — and how to get it done right the first time.
✅ When Does a Deck Require a Building Permit in Ontario?
In most municipalities across Ontario, a building permit is required for a deck if:
It is more than 10 square metres (≈ 108 square feet)
It is attached to the house
It is more than 24 inches (0.6 metres) above grade
It includes a roof, overhang, or enclosed structure
It requires guards or railings due to height
It alters grading or drainage on the property
If your deck meets any of the above criteria, you’ll need a permit — even if it’s at the back of your house or “just temporary.”
⚠️ When You Might Not Need a Permit
Some municipalities allow smaller decks or platforms without permits, if they meet all of the following:
Less than 10 sq. m.
Not attached to any structure
Less than 24 inches above ground
No stairs with more than three risers
Even if you think you’re exempt, it’s always best to check with your local building department or speak with a BCIN-certified designer.
📄 What’s Required to Get a Deck Permit?
To apply for a deck permit in Ontario, you typically need:
Permit drawings (site plan, framing plan, elevations)
Zoning review to ensure setbacks are met
Details about footings, beams, joists, and guards
BCIN-certified designer or engineer stamp (for most permit drawings)
The process varies slightly by municipality, but the core requirements are the same across the province.
🔧 Common Deck Permit Mistakes (and How to Avoid Them)
Submitting sketches instead of permit-ready drawings
Overlooking zoning setbacks or easements
Ignoring guard height or stair requirements
Building first, applying later (bad idea!)
The easiest way to avoid delays? Hire a designer who knows exactly what you need
🏗️ What If My Design Is Complex?
If your deck includes custom framing, cantilevers, or unusual loads, it may fall outside of Part 9 of the Building Code. That’s where a professional engineer is required.
At The Building Permit Guy, we handle that too — coordinating with our trusted engineers when needed to keep your project moving.
🎉 Special Offer: $50 Off Deck Permit Drawings
As a thank you for reading, we’re offering $50 off all deck permit drawings booked before Labour Day (September 1, 2025).
✅ BCIN-certified✅ Fast turnaround✅ Code-compliant✅ Designed for approval
📞 Contact us now or email info@thebuildingpermitguy.ca to claim this offer.
