How to Build a Multiplex in Toronto

Since May 2023, Toronto has permitted multiplexes of up to four units as-of-right in residential zones citywide. Under the City's current multiplex rules, six units are permitted as-of-right across the Toronto and East York district and in Ward 23 (Scarborough North). Other wards have an opt-in path but aren't automatically included, so sixplex permission is a question about where your lot is, not how big it is.

That count applies to the main building. A garden or laneway suite may be possible as a separate rear home, but only where the site and the applicable suite rules allow it; it is not an automatic extra unit.

As-of-right means a fully zoning-compliant design can proceed without a rezoning or minor variance. Building permits, zoning and bylaw compliance still apply, and a preferred design that exceeds the rules may need Committee of Adjustment approval. We've written more on what as-of-right does and doesn't give you, and on how the four-versus-six geography works.

This is the step people skip, and it's the expensive one to get wrong. Unit count affects which programs may be available, but it never establishes eligibility by itself.

The federal and Ontario purpose-built rental rebates may apply to a qualifying purpose-built rental project. Confirm the project's eligibility and tax treatment before putting any rebate into the budget.

CMHC MLI Select starts at five units, but property configuration, program criteria and underwriting still determine whether a project qualifies and on what terms. More on why five is an important threshold.

City fees, development charges and exemptions depend on the project. Check the City's current development-charge guidance for the specific proposal rather than assuming a unit count removes every charge.

Here is the part that surprises people: not every site is viable, and two lots with identical permissions can have completely different answers.

Permission is a ceiling, not a plan. What you can actually build is decided where three things meet — what the zoning allows, what the site itself can physically carry, and what the building code requires once you start drawing. That last one is easy to underestimate. Egress, fire separation, servicing and accessibility all consume floor area, and they consume it before a single square foot goes to the homes. A design that works beautifully on a wide lot can fail outright on a narrow one at the same permitted unit count.

Then the site imposes its own constraints. Lot geometry and access determine what can be staged and how it gets built. Soil conditions decide the foundation. Electrical supply deserves particular attention, because Toronto Hydro runs on its own timeline and that timeline doesn't bend to yours. Healthy trees are a real constraint, not a formality — they can't be removed to add units. Outside the core, parking requirements change the arithmetic again.

The cost drivers that actually move a multiplex budget are the product you're building, lot geometry, site access, soil conditions and any required servicing upgrades. We answer these questions before we acquire anything. Discovering them after closing doesn't just cost money, it costs months — see what it actually costs to build a multiplex in Toronto.

The output of this stage isn't a rendering. It's an honest answer about whether the site supports a project worth doing, and if so, which one. Our property feasibility checklist covers the information to gather before committing to a site or a full design.

Financing rental housing in Canada is its own discipline, and the sequence is counterintuitive: you need a view on your permanent takeout loan before you can tell whether the project is viable at all. That's a decision made at the beginning, not the end.

It's also a moving target. The debt products that make small rental projects work in Canada — CMHC's programs among them — change continuously, and the published summaries don't tell you everything that determines what you'll actually be offered. Rates, underwriting treatment and how a given lender reads your project are things you learn through relationships with brokers and lenders, and you have to keep learning them, because the answer this year isn't the answer next year.

The practical implication for a first-time builder is simple: start those conversations long before you think you need to, and assume the terms you model at the outset are provisional.

Permissions, feasibility and financing are the parts people plan for. Construction is the part that decides whether the plan survives.

You are sequencing trades on a small, tight urban site, usually with limited staging room and neighbours on both sides. You are holding the carrying cost of the land and the loan the entire time, so every week of delay is a real number. Permits and inspections arrive on the City's schedule, not yours — our approval timeline post covers where the delays actually sit. Servicing connections have long lead times that don't compress no matter how organized you are.

And drawings meet site conditions. Something is always different from what was assumed, and each of those moments is a decision made under time pressure, with cost attached, by whoever is standing there. Getting those right repeatedly is most of what separates a building that performs for fifty years from one that doesn't.

For most owners this is the honest sticking point. Not that it can't be done — that it's a full-time job with a long tail of small judgment calls, and you're learning it once, on the most expensive thing you own.

Before hiring, agree on who owns each stage and each handoff. Our guide to choosing a multiplex development team explains the roles and the questions to ask.

This is the problem we set out to solve for ourselves, and it's why we work the way we do.

Rather than treating every lot as a blank page, we've developed a set of building products designed for families — real homes with bedrooms, not the smallest units the code allows — that we adapt across the lot dimensions Toronto actually has. That means we come into a site already understanding what we're building and how we'll deliver it, and we can tell much sooner whether a property supports a project worth doing.

These stages are things we've already absorbed, rather than costs an owner takes on alone.

The two we have underway are different answers to different lots. FAMILY 1 is our product for the wider suburban lots that make up much of Toronto: five family-sized homes of roughly 1,300 square feet, each with three bedrooms and two and a half bathrooms. Three of the five homes include dedicated outdoor space. We acquired that site in April 2025, moved through design and approvals from May through August, had the building permit within four months of closing and broke ground in September 2025. The homes will be available for move-in November 15, 2026. The FAMILY 1 case study shows how those decisions played out on a real site. NEIGHBOUR 1 is seven homes, 500 to 1,400 square feet, for families at different life stages — our product for tighter urban lots.

If you own an underutilized lot in Toronto and want to understand what it could support, talk with us about the property.