How do you prepare a basement apartment / secondary suite permit application in Toronto?

Basement apartment / secondary suite permit preparation in Toronto: the application route, document checklist, official City guide and practical next steps.

Permit likely required

Adding a second dwelling unit in an existing house follows Toronto’s secondary suite building permit route.

A basement apartment is a common example. This differs from a finishes-only basement project. The City’s guide covers the drawings and related mechanical or plumbing submissions.

What changes the answer

Application routeUse the project-specific City guideInfo

Confirm the requirements against the official guide linked below.

Official sourceCity of TorontoBasement apartment / secondary suite application guide

Verified2026-09-30Open proof

Your preparation checklist

0 of 4 prepared

Preparation checklist for basement apartment / secondary suite. Reviewed 2026-09-30. Confirm the final submission requirements with the City.

Existing and proposed floor plans
Site plan
Building sections and construction details
Applicable mechanical and plumbing information

Fees and timing

TimelineConfirm the review stream after defining the project.

FeesUse the current City fee schedule for the proposed work.

Next steps

Define the second unit and shared areas
Review the City’s secondary suite guide
Confirm the complete submission package with your designer

Share this project guide

Send the guide to your designer or contractor before agreeing on the scope.

Related project guides

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