David Babakaiff
Written by David Babakaiff — Co-Founder, VanPlex | 25+ Years BC Construction

Building Types | Duplex

The Toronto Duplex: Two Units, the Simplest Multiplex

A duplex is two units in one building. It is the entry point to Toronto's multiplex permissions: the May 2023 multiplex by-law permits up to four units as-of-right in residential Neighbourhoods zones, so two units sit well inside that ceiling. A compliant duplex is a building-permit process, and it requires no parking.

Key Takeaways

  • A duplex is two units — well inside the four-unit as-of-right ceiling, city-wide.
  • No parking required for a duplex since February 3, 2022.
  • A compliant duplex is a building permit, not a rezoning.
  • The form least likely to exceed the zoning envelope.

Most Toronto lots permit more than two units. Check what yours allows before settling on a duplex.

From the City permit register

How many duplexes have actually been applied for

115
applications naming a duplex, since Jan 2024
106
distinct addresses
$800,000
median declared value, 92 projects
61
median days to issue, 94 issued

Since January 2024 115 new-build applications whose permit description names a duplex have been filed, across 106 addresses. That is 13.5% of all new multiplex applications in the city.

Counted a different way, 225 new-build projects citywide added 2 new homes. That figure is not the same thing: the City records new homes net of what was demolished, so a duplex replacing a house adds fewer than it contains.

Across the 92 of them that state a declared construction value, the median is $800,000, running from $550,000 at the 25th percentile to $1,000,000 at the 75th. That is the figure the applicant wrote on the application. It is not a sale price, it is not the finished cost of the build, and it excludes the land.

The City has issued 94 of them, taking a median of 61 days from application. That is 20 days faster than the citywide median of 81 days. 21 are still waiting and are not in that median.

New-build projects only, from the City of Toronto's Active and Cleared building permit registers. Conversions of existing houses, added basement suites, laneway and garden suites are counted separately and are not in these figures. See the full permit tracker for the method.

Two Units, Inside the Same Envelope as a House

A duplex does not get a special envelope. It lives inside the same as-of-right rules as any other residential building in the zone — the height overlay, lot coverage, and setbacks. Because two units are easy to fit, a duplex is the form least likely to push a design out of the building-permit stream and into a Committee of Adjustment variance.

That makes a duplex the natural starting point. A conversion that keeps the existing footprint usually fits the envelope cleanly. A side-by-side or stacked new build of two units sits comfortably within the height and coverage the same lot would allow for a single detached house.

No Parking, Since February 2022

Toronto removed most minimum parking requirements at Council in December 2021, in force February 3, 2022. Duplexes, triplexes, and fourplexes require no parking spaces. For a duplex that means you do not have to surrender yard or build a pad to satisfy a minimum — the space stays available for the building, landscaping, or a future rear-yard suite.

Best For

  • A first multiplex — the simplest two-unit form on a residential Neighbourhoods lot.
  • Converting an existing house where keeping the footprint fits the as-of-right envelope.
  • Owners who want a building permit with no rezoning and no public meeting.

Usually Fails When

  • The conversion adds height or coverage that exceeds the envelope and a variance was not planned.
  • The lot sits in a Heritage Conservation District that adds review.
  • Two units leave the project under-built on a lot that could carry three or four.

What To Verify Before Spending Money

  • The residential zone and Neighbourhoods designation for the parcel.
  • Whether the design fits the as-of-right envelope or needs a variance.
  • Whether a third or fourth unit would underwrite better on the same lot.

Where to Go Next

Frequently Asked Questions

Is a duplex permitted as-of-right in Toronto? +
Yes. The May 2023 multiplex by-law permits up to four units as-of-right in residential Neighbourhoods zones across Toronto. A duplex is two units, so it sits well inside that ceiling. A compliant duplex is a building-permit process — no rezoning, no Official Plan amendment, no public meeting.
Do I need parking for a duplex in Toronto? +
No. Since February 3, 2022, duplexes, triplexes, and fourplexes require no parking spaces in Toronto. The minimum parking requirement was removed, so a duplex does not have to provide a parking space to be approved.
What is the difference between a duplex and a triplex? +
Units, not process. A duplex is two units and a triplex is three. Both are permitted as-of-right city-wide and both require no parking. A triplex is the point where Ontario's Bill 23 three-unit floor and Toronto's by-law line up, but the application path is the same for both.
Can I convert an existing house into a duplex? +
A conversion is permitted where the design stays inside the as-of-right zoning — height, lot coverage, and setbacks. A conversion that keeps the existing footprint usually fits the envelope cleanly. A conversion that exceeds the envelope needs a minor variance from the Committee of Adjustment first.
Does a duplex have to fit a special envelope? +
No special envelope. A duplex lives inside the same as-of-right rules as any other residential building in the zone — the height overlay, lot coverage, and setbacks. Because two units are easy to fit, a duplex is the form least likely to push a design out of the building-permit stream.

Official Sources Referenced

General information, not legal advice. Zoning and permitting rules are set by each municipality and change over time. Verify current requirements directly with the municipal Planning Department before making a decision.

Related reading

Longer pieces on the same question.

PlexCheck Toronto

Two units may be well under your limit

Most Toronto lots permit more than a duplex. Before you settle on two, check what the by-law allows at your address.

Free. City-stamped zoning and CMHC survey rents. Takes about 30 seconds.

Check what you could build

Building in Toronto, not just modelling it

PlexCheck models any Toronto lot today. VanPlex does not yet build in Toronto or work with Toronto trades and lenders. Join the list and we will tell you when that changes.