The rule changes by municipality
Start with the city where the property is located.
Secondary dwellings are explicitly excluded from this permit class and use the general Building Permit route instead.
When a building permit is needed, Burlington’s accessory-structure route includes Pre-Building Approval, permit forms and construction drawings.
The City also states that structures larger than 10 m² or any structure containing plumbing require a building permit.
Larger or otherwise non-qualifying accessory structures require building-permit review. Zoning still applies.
Detached garages use the City’s housing permit framework with applicable forms, drawings and zoning review.
The application package requires site and construction drawings that show the proposed garage in relation to property lines, other structures and grading.
Ottawa’s garage guidance separates the small accessory-building exemption from the permit route for larger structures and still requires zoning compliance.
Detached garage applications use the City’s online intake. Attached garages follow the small residential additions route. Confirm the scope before choosing the application.
Vaughan’s accessory-structure route also calls for an approved lot grading permit and a fully dimensioned construction drawing set.
Waterloo uses a lower area threshold for detached garages than for storage sheds.
Ontario sets the Building Code. Municipal rules, zoning, processes and project guidance still differ.
We publish a city only after attaching municipal sources to the project answer. Missing coverage stays missing instead of borrowing another city’s rule.