Who qualifies for a Mississauga garden suite
Detached homes, semi-detached homes, and eligible townhomes can add one garden suite per lot. Townhome eligibility is narrower — corner and through lots in RM5 and RM6 zones typically qualify; standard interior condo townhouses generally do not.
One garden suite per lot. A basement or in-house second unit doesn't block you from also adding a garden suite (Mississauga permits up to three units per lot including the primary dwelling).
If you want a build-first summary of the program, start with our garden suite builder in Mississauga page.
The core rules
These are the dimensions a reviewer checks first. Your survey governs if it disagrees with anything below.
| Requirement | Minimum | Notes |
|---|---|---|
| Rear setback | 1.8 m | From the rear lot line. |
| Interior side setback | 0.6 m | Openings and grading can push this out. |
| Street-facing side setback | 2.5 m | Corner lots. |
| Fire route | 1.2 m × 2.1 m | Clear path from the street to the suite door, no longer than 45 m. Not a variance item. |
| Height and size | Per the ARU by-law | The pre-approved Studio (430 sq ft) and One-Bedroom (600 sq ft) are both drawn to comply. |
| Separate municipal address | $81.90 + HST | Required for the new unit. |
What those numbers mean for a specific neighbourhood is set out on our Mississauga garden suite page.
The 7-step permit process
| Step | What happens | Watch for |
|---|---|---|
| 1. Feasibility & zoning check | Confirm zoning, lot dimensions, and setbacks. Our instant zoning checker gives an immediate readout. | A map result is not a survey — measure the fire path with a tape. |
| 2. Choose pre-approved or custom | Studio 430 and One-Bed 600 are the free pre-approved options; custom means a designer. | Both layouts are in our plans catalogue. |
| 3. Site plan + grading plan | Prepared by a qualified professional. | Required even with pre-approved building plans. |
| 4. Permit application in ePlans | Reference the pre-approved model number; the building plans are not re-submitted. | Wrong or missing model number stalls intake. |
| 5. First review | Around 15 business days for complete applications; reviewers may return comments. | Each resubmission cycle restarts the clock. |
| 6. Fees & charges | Permit fee is paid at issuance and refunded after final inspection. Pay the $81.90 + HST address fee. | Second and third units are exempt from most development charges. |
| 7. Inspections to occupancy | Building, HVAC, plumbing, and electrical (ESA). | An optional kickoff meeting with Inspection Services heads off issues. |
What can go wrong (and how to avoid it)
- Incomplete submissions. Missing grading details, no arborist report where required, or missing service pipe sizing — each triggers a resubmission cycle.
- Non-conformance requiring a minor variance. If your design misses a setback or height rule by a small margin, you'll need a Committee of Adjustment application — adding 2 to 4 months.
- Water service decisions. Sharing the main service is cheaper but requires the Water Service Pipe Sizing Form and adequate existing capacity. Separate service through Region of Peel adds cost and coordination but future-proofs the property.
Frequently asked questions
Keep reading
Sources
- City of Mississauga — Additional residential units (garden suites)
- City of Mississauga — Building permits
- Ontario Building Code (O. Reg. 332/12)
- Bill 23, More Homes Built Faster Act, 2022
Municipal rules, fees, and programs change. Confirm current requirements with the city at application. Modular X provides exact pricing only after a site-specific feasibility review.
Disclaimer: Figures cited are market estimates provided for information only and are not a quote. Municipal rules, fees, and programs change — always verify current requirements with your local authority. Modular X provides exact pricing only after a site-specific feasibility review.