Toronto multiplex rules in 2026: four units city-wide, up to six in nine wards

How many units can your Toronto lot have?

Every residential zone allows a houseplex of up to four units; five or six are allowed only in nine wards. The zoning calls a multiplex a houseplex: one building on one lot with up to four units, at least one wholly or partly above another.

units in a houseplex in any R, RD, RS, RT or RM zone

4

units in a detached houseplex in nine wards

6

height, with no storey or floor space index limit

10.0 m

bedrooms at most in a fourplex

12

A fiveplex is not a separate permission: By-law 654-2025 allows “a detached houseplex with five or six dwelling units” in one rule. The building must be detached, on one lot, with a unit above another, and no part of a semi or townhouse can become a fiveplex or sixplex. In those wards, a “u” limit under 6 in the zone label rises to 6.

Three things that can change the count

• A site-specific exception (the “x” number in a zone label) can bind a houseplex to the exception's rules for a detached house. The zone's houseplex rules override it only for some limits, such as height and floor area, where they are more generous, so the exception's setbacks still apply.
• A former municipality's by-law: some lots are still zoned under one.
• Other routes to more units, with limits of their own, in R and RM zones and on lots on a major street: an apartment building where the zone label allows one, or, in the R zone, a house or half a semi built before December 15, 2023, converted to more units inside its walls (10.10.20.41).

The zoning limits that shape a multiplex

Height, main walls, depth, setbacks and lot coverage set the outline; a bedroom cap limits the units inside.

Height and main walls

• Height: 10.0 m, or the Height Overlay Map figure if higher, with no storey or floor space index limit (the “d” number).
• Five or six units may reach 10.5 m if the lowest level holds a unit, with ceilings of 2.4 m or more and ceiling joists 1.0 to 1.5 m above established grade over at least 80% of that level.
• Main walls (R, RD and RS zones): with a 10.0 m height limit, they stop at 7.5 m (2.5 m below the limit) along at least 70% of the side walls or 40% to 60% of the front and rear walls. A flat-roofed top storey stepped back at least 1.4 m at the front and rear can rise above that.

Depth, setbacks and lot coverage

• Setbacks: as for a house in your zone, such as an RD rear yard of 7.5 m or 25% of the lot depth, whichever is more.
• Lot coverage: where the Lot Coverage Overlay Map shows under 45%, a houseplex lot may cover 45% (RD, RS, RT and RM zones).

Entrances, balconies and parking

• Entrances: more than one front entrance is allowed.
• Balconies: in RD and RS zones, each unit may have up to two balconies or decks at the second storey or above, one at the front and one at the rear (on a corner lot, one may face the side street).
• Parking: none required, car or bicycle. The zoning's bicycle rates for homes apply only to apartment and mixed-use buildings, and bicycle spaces follow only if you choose to provide five or more car spaces.

Converting your house or building new

A conversion keeps what the house has; anything added outside must meet today's zoning.

Keeps what the house has

Convert inside the walls

If every new unit fits inside the building as it stood the day before the permit is issued, the house keeps its lawful status, setbacks included, even where today's rules ask for more (10.5.20.40). Five or six units follow the same rule, in a detached house only.

Today's zoning

Add on

Anything added outside is an addition and must meet today's zoning or get a minor variance.

Current Code throughout

Build new

A new building meets the current Building Code throughout.

Two breaks for narrower lots (10.5.40.71):

• On a lot 12.2 m (40 ft) wide or less, an addition built straight up over the existing walls keeps the house's existing setbacks.
• A rear or side addition keeps the existing side yards on a lot under 9.0 m wide; from 9.0 m to 12.2 m, it keeps half the required side yard, or the existing one if greater.

Additions of 100 m² or more, or a demolition, also bring the Residential Infill Public Notice.

The Building Code for a conversion

A house that has stood five years or more is renovated under Part 11 of the Ontario Building Code, whose compliance alternatives can replace Part 9 rules. Among them:

• Separations between units can be 30 minutes instead of 45.
• In a building of up to four units, one existing furnace can serve them all, with smoke alarms in each unit and a duct smoke detector that shuts it off (C156, C205).

What the Building Code adds from three units

From three units, the building is a multi-unit Part 9 building, provided it has no more than three storeys and 600 m² of building area (its footprint). The Code treats two units in one house as a “house with a secondary suite”, with lighter rules.

From three units: fire separations, a second exit, engineers

• Fire separations: in a new building, 45 minutes between units, and 1 hour around a unit on two levels, basement included, with none of the Type X drywall or sprinkler shortcuts a two-unit house can use (9.10.9.16); a converted house can use 30 minutes (C156).
• A second exit: a unit whose door opens onto a stair shared with other units, or onto a shared corridor with a single exit, needs a second, separate way out (9.9.9.3). This rule decides where the stairs go.
• Structure, HVAC and plumbing: an engineer, or a designer registered for that work, designs them, since the building is no longer a “house” (Div. C, Table 3.5.2.1); the City also wants plumbing drawings for each floor.

From four units: barrier-free design

In a new building, barrier-free design applies, since the Code exempts houses, duplexes, triplexes and townhouses, not fourplexes. Plan barrier-free entrances and a path through the entrance storey; other floors are exempt at this size (3.8.1.1, 3.8.1.2, 3.8.2.1). A converted house needs only some of these features (11.3.3.2).

Five or six units: a fire alarm

If more than four units share one exit stair or corridor, a fire alarm system is required once the building sleeps more than 10 people (the Code counts two per bedroom) or has over three storeys counting the basement, unless each unit has its own exterior exit to the ground (9.9.1.3, 9.10.18.2).

Does a multiplex need an architect?

Under Ontario's Architects Act, a multiplex needs no architect at three storeys or fewer and 600 m² or less of gross area. Gross area is every floor above grade, measured to the outside of the walls, so most basements don't count (s. 11(3)(a), 11(6)).

The Act's separate exemption for houses of up to three storeys never covers stacked units (s. 11(3)(b)).

Adding a garden or laneway suite

A fourplex lot can hold five homes. The City says a garden suite or laneway suite can share a lot with a multiplex if it meets its own rules, and the zoning allows one per lot, garden or laneway, not both (150.7.20.1).

With a fiveplex or sixplex

For five or six units, we read it as six plus one, and confirm it for your lot at the zoning review. The City's multiplex pages don't say so outright, but:

• Nothing in the garden suite chapter limits the units in the main building.
• City Planning's 2025 garden suite report counts up to seven units on a lot where sixplexes are allowed.
• The parkland rules count a suite as a seventh unit beside six (Municipal Code § 415-30 A(16)).

The suite's own limits

• Floor area: 120 m², or 60 m² if it is one storey, and less than the multiplex.
• Distance from the multiplex: 4.0 m, or 7.5 m if the suite is taller than 4.0 m.
• Rear lot line: at least 1.5 m away.
• Parking: two bicycle spaces and no parking.

The two buildings share the yard: every metre of multiplex depth comes out of the suite's space. Firefighters need a path from the street to the suite door, 1.0 m wide (0.9 m with sprinklers) and up to 45 m long, or 90 m with added fire-safety measures. So a 0.9 m side yard is wide enough only for a sprinklered suite's path.

Asking for more with a minor variance

When a design doesn't fit, the Committee of Adjustment can grant a minor variance. It can cover:

• a little more depth
• a narrower side yard
• more bedrooms
• more units than your area allows, such as a fifth unit outside the nine wards, though five units there make an apartment building in the zoning's terms, which may need a rezoning instead

That is possible, never guaranteed: each application is decided on its own facts, after public notice, against the Planning Act's tests (s. 45(1)).

A provincial rule that may make a variance unnecessary

A minimum setback on urban residential land is deemed to be 90% of the by-law's figure, so a 7.5 m rear yard can be 6.75 m as of right (Planning Act s. 34(1.4); O. Reg. 545/06). It doesn't apply:

• in the Greenbelt
• within 300 m of most rail lines
• within 120 m of a river or stream valley, an inland lake, a wetland or the Lake Ontario shoreline

City fees and charges in 2026

These are the City's 2026 figures. Our design fee is separate and quoted in writing.

The permit minimum is $214.79, and the zoning certificate fee is credited to the permit when you apply with the certificate.

How to start

Before the zoning review, gather:

• The zone label and any exception, from the City's zoning map
• The height, lot coverage and sixplex overlays, from the same map
• The lot's frontage and depth and the existing setbacks, from a survey

1. 01
   Design the units

   Test layouts against height, depth, bedrooms, exits and barrier-free entrances, and decide whether to convert, add or rebuild.

2. 02
   Zoning certificate, then any variance

   Apply for a Zoning Applicable Law Certificate (up to three reviews); without one, Toronto Building treats a permit application as incomplete. What doesn't fit goes to the Committee of Adjustment.

3. 03
   Permit drawings and forms

   Site plan, floor plans, sections and details, with structural, HVAC and plumbing drawings by an engineer or a designer registered for that work; a Schedule 1 from each BCIN-registered designer, the Tree Declaration and the Rental Renovation Licence Screening Form.

4. 04
   Submit and answer the examiner

   File online. Toronto Building reviews a complete application for three or more units within 15 business days and a new duplex within 10, and aims to review a house converted to two units within 3. The plumbing and HVAC permits can follow.

With your survey, we read the zoning, test the unit count and layout, and design the multiplex units with you. An engineer or a designer registered for that work designs the structure, HVAC and plumbing, and we coordinate their sheets with ours in one permit set.

Our ready-made multiplex layouts for common lot sizes can be a head start: our own designs, not City-approved plans, and each still needs its own zoning review and permit.