The BC Zero Carbon Step Code is a standard embedded in the BC Building Code intended to reduce carbon emissions in new construction.
Release Dates
The Zero Carbon Step Code - Emissions Level – 1 comes into effect across on March 10, 2025.
The Zero Carbon Step Code – Emissions Level – 3 comes into effect in Maple Ridge for Part 9 and Part 3 Residential Buildings on July 1, 2025.
The Zero Carbon Step Code is a new tool for the reduction or elimination of carbon emissions (known as "decarbonization") in the building sector. It addresses energy source emissions by encouraging mechanical systems that use energy sources with a lower carbon emissions factor in new buildings.
The Zero Carbon Step Code is a provincial BC Building Code standard introduced in the BC Building Code May 2023 update which sets greenhouse gas emissions targets for new buildings. Local governments can opt-in and reference it in their building or zoning bylaws and may apply different carbon performance levels, with increasing requirements.
Effective March 10, 2025, new buildings must meet at least EL-1 of the Zero Carbon Step Code.
This means that applicable buildings will be required to measure and disclose operational greenhouse gas emissions.
The Part 3 and Part 9 Step Code Compliance Checklists already disclose operational greenhouse gas emissions to the Authority Having Jurisdiction, so users of those checklists are already familiar with Greenhouse Gas (GHG) reporting.
Effective July 1, 2025, new buildings must meet at least EL-3 of the Zero Carbon Step Code for Part 9 and Part 3 Residential Buildings in Maple Ridge.
The four carbon performance or “emissions levels” (EL) of the Zero Carbon Step code are:
Measure-only (EL-1): requires measurement of a building’s emissions without reductions and is intended to build knowledge and capacity.
Moderate Carbon Performance (EL-2): in most cases, will require decarbonization of either space heating or domestic hot water systems.
Strong Carbon Performance (EL-3): in most cases, will require decarbonization of both space heating and domestic hot water systems; and
Zero Carbon Performance (EL-4): in most cases, will require the full electrification of a building.
The Zero Carbon Step Code applies to new buildings – Part 9 residential including single-family homes, row houses and low-rise multi-unit building and Part 3 larger and more complex buildings including offices, apartments and condominiums, hotels.
The Zero Carbon Step Code applies only to carbon pollution from space and water heating and cooking. It does not apply to wood stoves or decorative fireplaces, or auxiliary end uses such as clothes dryers, and, is not concerned with the emissions associated with construction materials (i.e., "embodied carbon").
Each step of the Code has a different Greenhouse Gas emissions intensity (GHGi) per square metre of building. An energy advisor would calculate the GHG emissions for a building design and work with the builder on modifications to meet a Zero Carbon Step Code level.
For Part 9 Buildings there is a Prescriptive Path or a Performance Path
For buildings like single-family homes, row homes, or small apartment buildings, builders and developers may either follow a prescriptive or performance approach.
Part 9 Buildings – Prescriptive or Performance Path
For buildings like single-family homes, row homes, or small apartment buildings, builders and developers may either follow a prescriptive or performance approach.
For Part 3 Buildings there is a Performance Path Only
When building large residential buildings, offices, retail buildings, and hotels and motels, the Zero Carbon Step Code requires builders to follow a performance path that sets targets for a building’s greenhouse gas intensity (GHGi)
The City of Maple Ridge is focussing on Part 9 residential and Part 3 residential buildings currently.
Mandatory Space Cooling
Though Zero Carbon Step Code is intended to achieve emissions reduction goals, implementation of EL-2 or Strong Carbon requirements also meet a new mandatory requirement under the March 2024 BC Building Code update. As a result of the 2021 heat dome that resulted in 619 heat-related deaths, the Province has enacted the following requirement in the most recent Building Code to limit risks associated with overheating in new homes:
"At the outside summer design temperature, required cooling facilities shall be capable of maintaining an indoor air temperature of not more than 26C in at least one living space in each dwelling unit."
Homes that are equipped with heat pumps, as would be required under the second step of the ZCSC or EL-2, would have central cooling throughout the dwelling thereby meeting the requirement. Therefore, Zero Carbon Step Code both mitigates Greenhouse Gas emissions while also providing adaptive benefits for climate change.
Maple Ridge Timelines
Effective March 10, 2025, new buildings must meet at least EL-1 of the Zero Carbon Step Code.
This means that applicable buildings will be required to measure and disclose operational greenhouse gas emissions. As of now, all new building permit applications will need to meet performance requirements specified in EL-1 (measure only) of the Zero Carbon Step Code. In other words, new building applications will have to include the modeled greenhouse gas emissions for the proposed building.
The Part 3 and Part 9 Step Code Compliance Checklists already disclose operational greenhouse gas emissions to the Authority Having Jurisdiction, so users of those checklists are already familiar with GHG reporting.
Effective July 1, 2025, new buildings must meet at least EL-3 of the Zero carbon Step Code for Part 9 and Part 3 Residential Buildings in Maple Ridge.
The City of Maple Ridge is implementing higher tiers of Zero Carbon Step Code (ZCSC) for Part 3 residential and Part 9 residential buildings only to prepare our community for the future of electrification, and to lower carbon emissions in the development and operation of new buildings.
The timeline is:
- Strong Carbon Performance (EL-3) on July 1, 2025
- Zero Carbon Performance (EL-4) on September 1, 2026
These timelines align with other Metro Vancouver municipalities that have introduced Zero Carbon Step Code for Part 9 buildings (EL-3 to EL-4 in 2023 to 2025) and Part 3 buildings (EL-2 to EL-4 in 2023 to 2025).
Related links
- BC Zero Carbon Step Code
- Information Bulletin - BC Building Code – 2018 – Revision 5, May 2023 Zero Carbon Step Code
- BCBC Revision 5 Amendments to the Zero Carbon Step Code that will require new buildings to meet at least EL-1 in Ministerial Order BA 2024 05 - effective date: March 10, 2025
- Building Officials Association of BC Zero Carbon Step Code Update
- 2023 Provincial Building Code Updates [PDF/486KB]
- Building Guides, Forms & Documents
- Building Permits & Inspections
- Building Bylaw
Contact Information
Building General Inquiries
Tel: 604-467-7311
Email: BuildingEnquiries@MapleRidge.ca