Ossington Avenue Housing, Toronto, Ontario

1120 Ossington Avenue Housing in Toronto, Ontario

July 9, 2026

Architecture: mcCallumSather

Location: 548 King St W Third Floor, East End, Toronto, Ontario, ON M5V 1M3, Canada

Photos: Riley Snelling and Liron Weissman

A new supportive housing development at 1120 Ossington Avenue is providing 25 permanent rent-geared-to-income homes for people exiting chronic homelessness while demonstrating an alternative approach to affordable housing construction.

Developed by St. Clare’s Multifaith Housing Society, the three-storey building occupies a surplus portion of land beside an existing church that had previously been converted into supportive housing. The infill project increases the number of affordable homes on the site without expanding the urban footprint or requiring new infrastructure.

mcCallumSather assumed responsibility for the project after municipal site plan approval had already been secured. The overall building form, footprint and exterior design had been established, leaving the team to complete the technical design, coordinate consultants and prepare the project for construction within the existing constraints.

Many building components were manufactured off-site before being delivered for assembly. The structural frame and enclosure were erected in just 17 days using three-ply cross-laminated timber (CLT) panels CNC-fabricated by Element5 from Ontario-sourced wood and tilted up on a narrow infill site with minimal disruption to the surrounding neighbourhood.

The project was designed to exceed the energy performance requirements established through the Canada Mortgage and Housing Corporation’s (CMHC) Rapid Housing Initiative. It features a high-performance building envelope, a Passive House-rated slab assembly and mechanical systems intended to reduce operational energy use. Energy modelling indicates performance approximately 40 percent better than the National Energy Code for Buildings (NECB) baseline. A building automation system will monitor actual performance after occupancy by tracking key energy-use metrics.

The confined urban site also required construction to proceed in stages. The rear portion of the building was assembled first to accommodate crane operations before work could continue at the front of the property. During construction, one interior wall was modified to gain approximately 3 inches of clearance in the kitchenette, allowing the unit to meet accessibility requirements without affecting the overall layout.

Each self-contained unit includes a kitchenette and private bathroom, while shared indoor spaces support community programming and resident services. Integrated metal screens designed by artist Leo Krukowski reference Indigenous and naturalized plant species and contribute to the building’s streetscape.

Delivering small, highly constrained housing projects requires the same level of technical coordination as larger developments, particularly when prefabrication is involved. Precision during design becomes critical because many construction decisions are effectively made before materials arrive on site.

Completed in December 2024, 1120 Ossington provides permanent affordable housing while offering a practical example of how mass timber, prefabrication and infill development can be combined to deliver supportive housing within the constraints of an established urban neighbourhood.

About mcCallumSather
mcCallumSather – https://www.mccallumsather.com/ is a Canadian-owned, multi-disciplinary team offering architecture, mechanical engineering and interior design. Our respect and appreciation for the environment runs deep, informing our thinking on decisions from building siting and orientation to material and system selection. Our team of experienced professionals share the goal of achieving design excellence and collective focus on sustainability. Our commitment to empowering teams, integrating with the construction industry, continuous learning and cultivating lasting relationships leads to inventive solutions that stand the test of time.