Corbett Ave | 02 Unit Conversion

Toronto

Property Type: Existing Single-Family Home

Project Overview:
This project began with the goal of converting a single-family home into a legal 2-unit dwelling, but the strategy went far beyond a basic retrofit. Due to existing basement ceiling height limitations, our team proposed full underpinning to meet the Ontario Building Code’s height requirements—allowing the basement to be converted into a fully compliant, livable unit.

To maximize the investment further, we also designed a rear-side basement addition, expanding the lower unit’s footprint and setting the foundation for a future 2-storey rear addition to be built above it.

Scope & Strategy:

• Proposed and designed full underpinning to achieve minimum 1.95m (6'-5") clear finished ceiling height in the basement.

• Integrated a rear basement addition to increase usable space and improve overall unit layout.

• Designed the basement addition’s foundation and structural system to support a future first and second floor extension—ensuring that once this permit is approved and built, the next phase can move forward without demolition or redesign.

Challenges Solved:

• Navigated structural and zoning complexities to permit basement expansion while aligning with long-term building plans.

• Ensured current permit scope (2-unit conversion) complies fully with fire separation, egress, and life safety requirements.

• Coordinated future-proof foundation design to support upcoming vertical construction.

Investor Benefits:

• Legal 2-unit conversion with increased square footage and premium basement livability.

• Construction efficiency and long-term cost savings by building the base now for vertical expansion later.

• Clear phased strategy that builds equity and rental income at every stage.

Current Status:
2-unit + basement addition permit approved! Full house addition planned as Phase 2.