Multiplex, Triplex and Fourplex Builder in Toronto

Toronto’s rules now let many homeowners build more than one home on a residential lot. Whether you want to convert an existing house into several units or build a new triplex or fourplex from the ground up, Ecocor Construction can take your project from the first zoning check to the final inspection. We have been designing and building in Toronto since 2016, with 157+ completed projects and 19+ industry awards.

What Toronto allows

In 2023, the City of Toronto began permitting multiplexes, buildings with up to four units, in residential neighbourhoods across the city, subject to zoning rules on height, depth, setbacks and landscaping. Since then, the City has expanded permissions further in some parts of Toronto. The rules continue to change, so the first step on every project is confirming exactly what your lot allows today.

New build or conversion?

Converting an existing house. Some houses can be divided into a triplex or fourplex by reworking the layout, adding separate entrances, creating fire separations between units and upgrading services. Whether this makes sense depends on the structure, the height and the condition of the house.

Building new. On other lots, it is more practical to take down an older house and build a new multiplex designed for separate units from the start. That gives you more control over layouts, sound separation and energy performance.

We help you compare both options before you commit.

How we deliver a multiplex

1. Feasibility and zoning review. We look at your lot size, frontage, existing building, services and zoning to see how many units are realistic.

2. Design with architects and engineers. Multiplexes need careful design. We collaborate with architects, engineers and interior designers to plan units people want to live in, with good light, storage and privacy.

3. Permits and approvals. We coordinate drawings for the City of Toronto building permit, and plan for Committee of Adjustment if a minor variance is needed. Multi-unit buildings must meet Ontario Building Code requirements for fire separation, exits and sound between units.

4. Construction. Our team manages the build and the trades, and keeps you updated as each unit comes together.

5. Handover. We walk every unit with you and confirm the required inspections are complete.

Who builds multiplexes?

Our multiplex clients include families who want to live together under one roof with private units, homeowners who want rental income to help with costs, and owners planning long-term housing for the next generation. Not ready for a full multiplex? Consider a secondary unit or a laneway suite.

Frequently asked questions

Can I build a fourplex on my Toronto lot?

Many residential lots in Toronto now permit up to four units, but each lot must meet zoning rules. We review your property before design starts.

Is it better to convert my house or build new?

It depends on your house’s structure, height and condition, and on your goals. We compare both options with you.

Do you have in-house architects?

No. We collaborate with outside architects, engineers and interior designers, and Ecocor coordinates them with the construction.

Can units in a multiplex be sold separately?

Not by default. A multiplex usually stays one property unless it is later set up as a condominium, which is a separate legal process. Get legal advice if this matters to you.

Planning a triplex, fourplex or multiplex in Toronto? Book a consultation or call 416-500-5222.