CaGBC® Zero Carbon Building Standard:
Frequently Asked Questions


Table of Contents

  1. What is a zero-carbon building?
  2. What is the Zero Carbon Building Standard?
  3. Who can use the Standard?
  4. What’s new in ZCB Standard v2?
  5. How do you show that you are certified?
  6. Did you consult the industry?

1. What is a zero-carbon building?

A zero-carbon building is a highly energy efficient building that produces onsite, or procures, carbon-free renewable energy or high-quality carbon offsets to offset the annual carbon emissions associated with building materials and operations.

2. What is the Zero Carbon Building Standard?

To direct the built environment and Canada’s building industry toward achieving Canada’s climate change commitments, the CaGBC launched the country’s first Zero Carbon Building Standard. This Standard assesses carbon use across many types of new and existing buildings. At the time of its launch in 2017, it was the only program of its kind to make carbon reductions the key indicator for building performance.

The Standard’s focus on carbon pollution is crucial, as the most important factor in the carbon footprint of a building is often not its energy efficiency, but its choice of energy sources. In 2020, CaGBC released Zero Carbon Building Standard v2. The v2 update goes beyond operational carbon emissions to look at a building’s embodied carbon from a life-cycle perspective.

3. Who can use the Standard?

The CaGBC’s Zero Carbon Building (ZCB) Standard is designed to allow owners of both new construction projects and existing buildings to apply for certification. It is applicable to all buildings except homes and small multi-family residential buildings. Specific requirements address design and performance verification:

  • The ZCB-Design Standard provides requirements that guide the design of new buildings and the retrofit of existing ones, to best empower buildings to achieve zero carbon operations.
  • ZCB-Performance Standard verifies that buildings achieve zero carbon operations year after year.

4. What’s new with ZCB Standard v2?

The updated ZCB Standard improves on the original, based on real-world feedback from 15 pilot projects across the country. The changes made balance the need for emissions reduction with the need to galvanize Canada’s building owners and developers to ensure all buildings contribute to Canada’s carbon targets. Key improvements include:

Embodied carbon and refrigerants

The ZCB Standard v2 requires projects to offset the embodied carbon in construction materials. Emphasis was placed on reducing the carbon associated with the building’s whole life-cycle, Including emissions from the production of construction materials, which the industry calls "upfront carbon.

The updated v2 also tackles refrigerants used in heat pumps. While heat pumps are extremely efficient, the refrigerants most often used are “near-term climate forcers” – GHGs that last a short time in the atmosphere but trap a lot of heat. With v2, the Standard encourages the use of best-management practices to minimize potential leaks, and any leaks that might occur must be offset.

Carbon offsets

ZCB Standard v2 allows for the purchase of carbon offsets to compensate for embodied carbon and ongoing building operations, opening the door for more buildings to reach zero — and for owners to align with their corporate sustainability objectives.

Energy Efficiency

The updated ZCB-Design v2 raises the bar on energy efficiency, while ensuring there is a path for every building by providing three compliance options. The first focuses on balanced thermal energy demand intensity (TEDI) and energy use intensity (EUI) objectives; the second focuses on deeper reductions in thermal energy demand; and a third option includes a TEDI target and recognizes projects for achieving zero carbon through on-site measures without relying on green power or carbon offset purchases. ZCB-Design v2 certified projects must also perform air leakage testing before they can earn ZCB-Performance certification, helping drive improvements in the energy efficiency of the building envelope.

Impact and Innovation

The ZCB-Design v2 encourages new and meaningful technologies and design approaches by requiring projects to demonstrate two impactful and innovative strategies to reduce carbon emissions. Applicants can propose their own strategies, providing broad flexibility while helping to build skills and develop markets for low carbon products and services.

Please refer to the ZCB-Design v2 and ZCB-Performance for detailed requirements.

5. How do you show that you are certified?

CaGBC has developed a certification mark that can be used on promotional material including web copy, ads and other marketing material that are related directly to the project. Buildings that achieve ZCB-Performance Standard certification can promote their accomplishment with a plaque.

6. Did you consult the industry?

The Zero Carbon Building Standard v2 was developed through extensive consultation with experts and stakeholders across the country over a two-year period.

Revisions to the Standard were informed by the Zero Carbon Pilot Program, an initiative designed to facilitate peer learning and capacity building amongst a group of sixteen project teams that committed to the two-year immersion program prior to the launch of registration for the ZCB Standard. The pilot program recognized excellence and leadership, and served to inform the development of tools, policies, and pathways to accelerate market transformation. The lessons learned from the pilot program assisted the CaGBC in identifying opportunities to refine the ZCB Standard.

In 2019, a series of zero carbon roundtables were held across the country to collect feedback on the ZCB Standard and to discuss the challenges and opportunities in different regions of the country. Three working groups were also formed, bringing significant subject matter expertise to the development process. The working groups – focused on energy metrics, carbon accounting, and embodied carbon – reviewed the feedback received through the pilot projects and roundtables and made recommendations to the Zero Carbon Steering Committee. The Steering Committee worked with CaGBC staff to develop a list of final recommendations.