By Sara Rahgozar, M.Arch, OAA, Quadrant Architects
On top of the units you can build in your main house, Toronto lets you add one more home in a separate structure in the backyard. It is the unit that takes a fourplex to five homes, or a sixplex to seven, on a single lot.
There are two kinds: the laneway suite and the garden suite. Which one you can build comes down to a single question, whether your lot backs onto a public laneway. This guide covers both, and how they stack on top of your multiplex units.
It is the laneway. If your lot backs onto a public laneway, you build a laneway suite, which faces the lane and is entered from it. Permitted city-wide since July 16, 2019, under the Changing Lanes initiative. If your lot has no laneway, you build a garden suite, which sits in the rear yard. Permitted city-wide since February 2, 2022.
Both are self-contained detached homes, secondary to the main house, and both are allowed in the R, RD, RS, RT, and RM residential zones. You can build one or the other, never both, because Toronto permits one accessory dwelling unit per lot.
The backyard suite is a separate permission from the multiplex by-law, so it does not count against your main building’s units.
The main building follows the multiplex rules; the backyard suite follows its own, either the Changing Lanes by-law for laneway suites or the garden suite provisions. Two rule sets apply on the same lot, so confirm the combined unit count and envelope with the City.
The two are close in most respects. Here is how they compare.
| Laneway suite | Garden suite | |
|---|---|---|
| Lot requirement | Backs onto a public laneway | No public laneway; suite sits in the rear yard |
| Maximum size | Up to 120 sq m above grade, and no larger than the main house | Up to 120 sq m above grade |
| Maximum height | Two storeys | Two storeys |
| Car parking | None required | None required |
| Bicycle parking | Two spaces | Two spaces |
| Roof | Flat and shed roofs allowed (angular plane rule removed in 2025) | Flat and shed roofs allowed (angular plane rule removed in 2025) |
The lot has to abut a public laneway, one the City maintains, not a private drive. The suite entrance must be within 45 metres of a public street along the lane, or 90 metres via the main house, and there has to be a clear path at least 0.9 metres (3 feet) wide to the entrance. Setbacks from the laneway and neighbouring properties apply. The 2025 housekeeping update (Laneway By-law 847-2025, adopted July 24, 2025) aligned the laneway rules with provincial Ontario Regulation 462/24.
The rear yard needs adequate access, including fire department access. A garden suite cannot be severed from the main lot or sold separately under current zoning. One local rule to watch: in parts of the former Etobicoke, including Mimico, New Toronto, Long Branch, and Islington, garden suites carry a 30-metre minimum lot-depth consideration that does not apply the same way elsewhere. Etobicoke lots are often wide and deep, but a shallow one can be disqualified before you start, so confirm your lot depth against the current rule first.
It depends on your total unit count across the lot. If the total, main building plus the suite, is six or fewer, development charges are fully waived, the suite included. If the suite brings you to seven or more, it is no longer exempt, but you can apply to defer the charge, and it is waived only if you keep the suite as a rental for 20 years or more. You can build the suite before, after, or alongside the multiplex without affecting the waiver on the main building’s units.
Laneway and garden suites typically run $300 to $400 or more per square foot, depending on site conditions, finishes, and how the project is managed. For the same amount of space, that is roughly half the all-in cost of a downtown Toronto condo. A well-located two-bedroom laneway suite rents for about $3,000 to $3,300 a month at current rates.
A few things drive cost beyond the building itself: running water, sewer, electrical, and gas to the back of the lot, which means trenching through an established yard; protected trees in the build zone, which can require an arborist report and can limit where you build; soil conditions, especially with a high water table or fill; and getting materials and equipment to the rear of the lot through a narrow side yard or lane.
Yes. The City has introduced financing to support backyard suites: loans of $80,000 at 2 percent interest for a basement, garden, or laneway suite, announced for 2025, and up to 90 percent loan-to-value financing that includes the added value of the new suite, which means many owners can build with little out of pocket. Check current availability and eligibility with the City and your lender.
Yes, and they can save time and money. The City has released free pre-approved garden and laneway suite plans, already reviewed for code compliance, which shortens the permit process. It has also enabled self-service permit submissions for laneway suites, garden suites, multiplex conversions, secondary suites, and new houses, and published demonstration plans showing where these can be built across the city.
For a laneway suite, confirm that your rear or side lot line abuts a public laneway, that you can meet the distance and path-width rules above and the setbacks from the laneway and property lines, and that the build zone is free of protected trees.
For a garden suite, confirm that your lot has no public laneway, that it is deep enough to hold the suite behind the main house with the required setbacks (including the 30-metre depth consideration if you are in Etobicoke), that there is fire department access to the rear yard, and that the build zone is clear of protected trees and other obstructions.
Once the applicable points check out, the next step is a conversation with an architect or a BCIN-qualified designer. It is part of what we do as a multiplex architect.
Sara Rahgozar, M.Arch, OAA, Quadrant Architects. 416-357-5713 · sara@quadrantarchitects.com
Current as of August 2026, reflecting the 2025 housekeeping updates (By-laws 847-2025 and 849-2025) and alignment with Ontario Regulation 462/24. Rules and financing programs change. Verify current requirements through the City of Toronto before making design or investment decisions.