Legal Basement Apartments and Secondary Units in Toronto

A legal secondary unit can turn unused space into rental income, a home for adult children or aging parents, or a private suite for a caregiver. Ecocor Construction has designed and built homes and renovations in Toronto since 2016, and we take secondary unit projects from the first site visit through permits, construction and final inspection, so the finished suite is safe, comfortable and legal.

Why “legal” matters

Not every finished basement with a kitchen is a legal unit. To be recognized as a secondary unit, the space needs a City of Toronto building permit and has to meet the Ontario Building Code and the Ontario Fire Code. Those rules cover things like fire separation between units, smoke and carbon monoxide alarms, safe exits and window sizes, ceiling height, and separate heating, ventilation and electrical considerations. A suite built without a permit can cause problems with insurance, resale and tenancy down the road. Building it properly from the start protects you and the people living there.

What Ontario and Toronto allow

Ontario law now allows up to three residential units on many residential lots, for example a main house, a basement unit and a garden or laneway suite, subject to local zoning. In Toronto, that means many homeowners can add a secondary unit in the basement or elsewhere in the house. Every property is different, so we review your home’s layout, height, exits and zoning before you commit.

How we build your secondary unit

1. Site visit and feasibility. We check basement height, the foundation, exits, windows and existing plumbing, electrical and mechanical systems to see what your space can support.

2. Design and drawings. We work with designers and, where needed, architects and engineers to lay out a suite that meets code and still feels like a home: a full kitchen, a bathroom, bedrooms and good light.

3. Permit application. We prepare and coordinate the drawings needed for the City of Toronto building permit.

4. Construction. Our team handles the work in sequence: framing, any underpinning or lowering, fire separation, plumbing, electrical, insulation, drywall and finishes, with the inspections the permit requires along the way.

5. Final inspection and handover. We walk through the finished unit with you and confirm the required inspections are closed.

Designed for real living

A good secondary unit should not feel like a basement. We focus on layout, natural light, sound control between units and durable finishes that stand up to everyday life. If you are planning more than one extra unit, see our pages on laneway suites and multiplexes.

Frequently asked questions

Can every basement become a legal apartment?

No. It depends on ceiling height, exits, window sizes, the foundation and zoning. A site visit tells us what your basement can support and what work would be needed.

Do I need a permit to add a secondary unit in Toronto?

Yes. Creating a new dwelling unit needs a City of Toronto building permit, and the unit must meet the Ontario Building Code and Fire Code.

Can I add a basement unit and a laneway or garden suite on the same lot?

On many Toronto lots, yes. Ontario rules allow up to three units on many residential properties, subject to zoning. We confirm what applies to your lot.

Do you handle the drawings and the permit?

Yes. As a design-build company, we coordinate the drawings with designers and engineers and manage the permit process with you.

Thinking about a legal basement apartment? Book a site visit or call 416-500-5222 and we’ll tell you what your space can become.