Review Tips for NECB Energy Modelling Guidance under LEED v4/4.1
Projects in Canada have the option under LEED v4 to utilize the National Energy Code for Buildings (NECB) 2011 through a Canadian specific Alternative Compliance Path (ACP). Canadian project teams can also utilize an energy code version that is similar to their local code adoption through the pilot ACP EApc143 Zero Energy Performance Index (zEPI) (LEED v4 or LEED v4.1). The zEPI ACP allows project teams to utilize NECB 2015, 2017 or 2020.
Occasionally project teams have reached out to CAGBC for modelling guidance on LEED v4/4.1 with NECB. Additionally, while the Canadian ACP for NECB 2011 provides a number of descriptive conditions for LEED models, the zEPI ACP has more limited guidance, and project teams have raised these challenges to CAGBC. CAGBC’s Energy & Engineering Technical Advisory Group (TAG) have responded with answers for project teams encountering these issues within their energy models and are happy to share this direction.
The topics in this document range across a breadth of modelling concerns:
- NECB 2011 Radiant Effects (NECB 2011 8.4.4.17. Space Temperature Control)
- NECB 2017 – Outdoor Air Rates
- Ventilation and Supply Flow Rates where owner has higher minimum air change rates
- HVAC System Selection in stairwells, and similar spaces
- Service Hot Water Flow Rates
- Heating Fuel Switching (within NECB 2017 and similar)
- NECB 2017 Reference Energy Recovery System
- Handling modeling of envelope for a Major Renovation using NECB 2015, 2017, or 2020 under the zEPI ACP.
- Modelling small fans under NECB path
- Modeling Snow Melt under NECB
Project teams which feel their energy models cannot accommodate this direction should reach out to the CAGBC in advance of submitting to ensure a smooth review process.