Dana and Steve Gazzola bought their house on Southlea Avenue for the yard. It backs onto a quiet lot on Astor Avenue, the kind of sightline that made the whole property feel bigger than its footprint. Then a new owner took over the Astor Avenue lot and pulled a permit for a duplex. What went up was a three-storey house with an in-law suite, built at a scale the Gazzolas say changed how their own backyard feels. Toronto's building inspectors have visited the site more than once. They have raised no objections. The permit is legal.
That contradiction is the story worth understanding if you are pricing a Leaside lot, watching construction go up next door, or trying to figure out what Toronto's multiplex reforms actually mean for this specific neighborhood. Most zoning guides will tell you Leaside caps out at four units while wards just south of Eglinton allow six. That's true, but it's the smaller fact. The bigger one is that a permit built for adding rental housing can, structurally, be used to build a much larger house for one family instead, and nothing in the current rule set stops it.
A Duplex Permit, Not a Rezoning
The Astor Avenue project didn't need a rezoning application, a Committee of Adjustment hearing, or public notice. Since 2023, Toronto has allowed property owners to add up to three units on top of an existing single-family lot as-of-right, anywhere in the city. A duplex, which adds just one unit, is the lightest version of that permission. The owner, Behnam Rashidi, has said the finished house will hold only family members. City staff have confirmed there is no hard distinction in the current rules between a secondary suite, which must be smaller than the primary dwelling, and a duplex, which can be built at a much larger scale with its own entrance and smaller setbacks from neighboring properties.
Geoff Kettel, co-chair of the Leaside Residents Association, has called the street a tight-knit one that has come together over the dispute. Local councillor Rachel Chernos Lin, who represents Don Valley West, has said publicly that the lack of a clear line between a secondary suite and a duplex creates an incentive for builders to construct oversized single-family homes without adding to the housing supply the policy was meant to expand. She wants that gap closed.
None of this means the Astor Avenue project broke a rule. It means the rule, as written, doesn't require the second unit to ever function as a rental, or to be occupied by anyone outside the owner's family. A permit built for density can produce a bigger house instead.
What Leaside's Zoning Ceiling Actually Is
Set the Astor Avenue case aside for a moment, because the ceiling itself is worth getting right. In June 2025, Toronto City Council voted to allow buildings of up to six units as-of-right, but only in nine wards: eight in the old Toronto and East York district, including Parkdale-High Park, Davenport, Spadina-Fort York, University-Rosedale, Toronto-St. Paul's, Toronto Centre, Toronto-Danforth, and Beaches-East York, plus Scarborough North as a pilot ward. Every other ward in the city, including Leaside's Ward 26, Don Valley West, was left at the four-unit ceiling the city adopted city-wide back in 2023. A councillor can request that their ward opt into the six-unit permission, but as of this writing no ward outside the original nine has done so.
If you've been told Leaside picked up sixplex rights because it sits close to the East York core, that's not accurate for the current rule set. Leaside is fourplex-only, the same as most of the city.
The Gap Is Smaller Than the Ceiling Suggests
Here's where the ceiling matters less than it first appears. Toronto's most valuable multiplex incentives don't scale up with the unit cap. They apply identically whether you're building four units in Leaside or six units in a ward that permits it.
| Leaside (Ward 26) | A sixplex ward (for example, Ward 14, Toronto-Danforth) | |
|---|---|---|
| As-of-right unit ceiling | Four | Six |
| Development charges on qualifying units | Waived | Waived |
| Minimum on-site parking required | None | None |
| Garden or laneway suite stacked on top | Permitted, adds a unit | Permitted, adds a unit |
| Rezoning or public meeting for a compliant build | Not required | Not required |
Toronto's development charges on a conventional project outside the waiver typically run $40,000 to $55,000 per unit, and the waiver on a qualifying multiplex represents roughly $160,000 to $270,000 in savings depending on how many units are built, a figure the city's own multiplex framework has held steady through 2026. That waiver applies at four units in Leaside exactly as it applies at six units in a sixplex ward. So does the elimination of minimum parking, in place since February 2022. The two-unit difference in the ceiling is real, but the dollar value of the policy's biggest lever doesn't move because of it.
Why the Foundation Matters More Than the By-Law
If the ceiling isn't the constraint, what is? In Leaside, it's the housing stock itself. Most of the neighborhood's detached and semi-detached homes date from the 1920s through the 1950s, built on regular lots with basements that were never designed for the ceiling heights a legal unit requires. Converting that basement into a code-compliant dwelling usually means underpinning, lowering the floor to gain clearance, which is one of the larger and less visible costs in any conversion budget. A wider lot with a solid, square footprint gives a builder more room to work with than a narrower or shared-wall property, regardless of what the zoning technically allows.
Heritage character adds a second layer. Exterior changes on a heritage-flagged property, including a third-storey addition or anything visible from the street, typically require a separate Heritage Permit review, which can add months and tens of thousands of dollars to a project timeline. None of that shows up on a zoning map. It shows up when a contractor walks the actual house.
What This Means If You're Pricing a Leaside Lot
For a buyer or investor comparing Leaside against a sixplex-eligible ward, three things follow from all of this.
First, don't let the ward map do more work than it should. The financial case for a fourplex conversion in Leaside, once you factor in the waived development charges and eliminated parking requirement, is closer to the sixplex-ward case than the headline ceiling suggests. The real gap is two units, not the full economics of the project.
Second, a "duplex" listing or a duplex permit on a construction site next door tells you less than it sounds like it should. It does not guarantee two independently rentable units, and it does not cap the size of what gets built. The Astor Avenue project is proof that the same permit built to add housing can be used to build one larger house instead.
Third, underwrite the foundation and the streetscape before the zoning. A Leaside lot's real ceiling is usually set by basement depth, lot width, and whether Heritage Preservation Services will scrutinize the addition, not by the four-unit cap that applies almost everywhere in the city anyway.
A Few Direct Answers
Can I build a sixplex in Leaside? Not as-of-right. Leaside sits in Ward 26, which is outside the nine wards council approved for six-unit buildings in June 2025. The as-of-right ceiling here is four units unless the ward opts in, which hasn't happened.
Does a duplex permit guarantee a second rental unit gets built? No. A duplex permit allows a second unit, but current city rules don't require that unit to be rented, occupied by anyone outside the owner's family, or built at a smaller scale than the primary house. The Astor Avenue case in south Leaside is a live example.
What should I ask about before buying next to an active permit in Leaside? Ask what type of permit was pulled and what the applicant has said about occupancy. A duplex or multiplex permit tells you what's legally possible, not what's actually being built or who will live there.
Zoning maps answer one question. Foundations, streetscapes, and how a permit gets used answer the ones that actually determine what a Leaside property is worth to build on. If you're weighing a lot here against something in a sixplex ward, or trying to read what a construction permit next door really means for your own home, Taylor Townley can walk the specifics with you and help you separate the zoning headline from the underwriting that matters.
