25 St. Clair East Rehabilitation Project
A zero carbon model for the Canadian government
Office & Workplace, Renewal

The 25 St. Clair East Rehabilitation Project presented a significant challenge: preserving as much as possible from two 1950s era office buildings while improving their function and performance. 25 St. Clair East is a pilot project in the Canada Green Building Council’s zero carbon initiative, and will be the federal government’s flagship for sustainable building. The new design is LEED Platinum certified and will reduce greenhouse gas emissions by over 80%, putting occupant health and wellbeing first.
The project combines two buildings into one, with a new façade and a visual separation that runs diagonally across the building. This is manifested an unbroken open staircase that allows active circulation within the space while permitting an abundance of light to filter towards the back of the deep floorplate. Given the unique user groups and the building’s purpose, DIALOG centered the design around the principles of J.E.D.I.—Justice, Equity, Diversity, and Inclusion.
- Location
- Toronto, ON
- Size
- 442,235 sq ft
- Client
- Government of Canada
- Completion
- 2023
- Sustainability LEED Platinum Certified
- DIALOG Services
- Collaborators
Two Row Architect
RDH Building Science
The Attain Group
LOBO
LEA Consulting
Entro
Architecture
Electrical Engineering
Interior Design
Mechanical Engineering
Structural Engineering
Sustainability + Building Performance Consulting
The Team
Steven MacKinnon, Parliamentary Secretary to the Minister of Public Services and ProcurementThis project embodies our commitment to improving how we manage the energy performance of federal buildings. Through this and other initiatives across government, we are taking steps to reduce our [carbon] footprint and green our buildings.