Zero Carbon Step Code

The Zero Carbon Step Code was included in the BC Building Code May 1, 2023.  The Zero Carbon Step Code establishes Carbon Performance tiers which align with carbon emissions levels associated with the energy used by the building’s systems. The Zero Carbon Step Code supports electrification of new construction and reduction of greenhouse gas emissions.

The ZCSC establishes Emission Levels, which includes a measure only option. The Emission Levels align with specified modelled performance values for an upper limit of greenhouse gas emissions from a new buildings.

In general, the requirements of the Carbon Performance tiers are:

  • Measure-only (Emission Level 1) – requires measurement of a building’s emissions without reductions;
  • Moderate carbon (Emission Level 2)  – in general requires electrification of either space heating or domestic hot water systems:
  • Strong carbon (Emission Level 3) - in general requires electrification of both space heating and domestic hot water systems; and
  • Zero carbon ready (Emission Level 4) – in general requires the full electrification of a building

The BC Building code establishes maximum modelled greenhouse gas emissions for each Emissions Level. Details of requirements to meet each Emission Level can be seen in the BC Building Code convenience copy here.

Similar to the Energy Step Code (ESC), the Province has indicated the intent to incrementally increase the required level of the Zero Carbon Step Code (i.e. decreasing levels of greenhouse gas emissions) in future Building Code updates to meet the CleanBC target of Zero Carbon new buildings by 2030. Zero Carbon Step Code requirements are anticipated in the 2024 and 2027 building code updates, but it is unclear what carbon performance levels will be required at those milestones.

The City of New Westminster has established a proposed timeline to reach highest level of the Zero Carbon Step code.