Canada's first federal carbon-neutral building

The 25 St. Clair rehabilitation project is set to become one of Canada's first federal carbon-neutral buildings. It supports the government's commitment to greening its operations and serves as a flagship model of the government's commitment to achieve net-zero greenhouse gas (GHG) emissions by 2050.

Following a 2015 feasibility study project, the Canada Green Building Council requested that Public Services and Procurement Canada (PSPC) consider pursuing a zero-carbon pilot project. With such a significant shift in the design, the project team was motivated to make the project as energy efficient as possible by creating or reusing energy within the building.

The building is designed to reduce GHG emissions by almost 80%, saving over 700 tonnes of carbon dioxide emissions per year; that's the equivalent of 124 homes' electricity use for 1 year. To reach this ambitious objective, the team opted for solar electricity, which means that 850 photovoltaic panels will be installed on the roof to generate renewable power. These solar panels will help power the building and will reduce energy use by about 15%.

To reduce landfill and energy use, the existing main structural components of the building (the floor slabs, roof and columns) will be maintained as part of the renovation. Digital controls throughout the building will allow for better regulation of lighting and systems (Heating, ventilation, and air conditioning, plumbing and electrical) for the increased comfort of occupants, as well as reduced energy use.

A geothermal system will be installed under the existing garage to offset heating and cooling loads. Geothermal systems are the greenest and most energy-efficient systems in the world as they can help save up to 70% on heating, cooling and hot water costs.

The result was a success. By incorporating all of these elements, the project received the Canada Green Building Council's Zero Carbon—Design certification in 2022. This certification means that the building will emit no GHG emissions or will offset its emissions.

Environmentally friendly inside and out

While we talk a lot about energy savings and reducing GHG emissions, all aspects of the environment remain at the centre of this project, such as care for wildlife and lower water consumption.

Using bird-friendly glazing with a distinctive pattern will help reduce bird-to-building collisions and mortality. Rain water from the roof will be collected for reuse in the building-mechanical systems.

Transportation also plays a key role in adopting a greener environment. About 40 electric vehicle charging stations will be installed, along with interior bicycle storage spaces and showers and lockers to encourage greener transportation. Occupants will also have easy access to public transportation through connections to the Toronto Transit Commission subway and streetcars.

The project will apply the Government of Canada Workplace (GCworkplace) standards, which will result in an estimated overall space saving of 9,000 square metres. Once complete, the building will accommodate several government departments and agencies. The significant sustainability elements of this project will contribute to the Government of Canada's commitment to greening its operations. To learn more, visit PSPC's Departmental Sustainable Development Strategy.

Not only will 25 St. Clair be at the forefront in terms of greening, but also in terms of accessibility. To learn more about other aspects of the project, visit the article 25 St. Clair in Toronto: Accessibility 3.0.