Summary
This is a Building Performance Insights report from the Performance Insights project. View the main page for additional context.
City of Calgary Part 3 Performance Path Study:
Multi-unit residential buildings (MURBs), NECB 2020: Energy performance and breakdown of energy tier
- Energy Tiers: The vast majority (96%) of MURBs are being built to the minimum energy performance Tier 1. Within the Tier 1 buildings, the median performance is 12.6% better than the reference building.
Multi-unit residential buildings (MURBs), NECB 2017: Energy performance
- Energy savings: NECB 2017 has no performance tiers, so results are reported as savings against the reference building. Every building modelled better than the minimum requirement, with improvements spread across the full range and a small number above 40%.
Industrial, Commercial and Institutional (ICI), NECB 2020: Energy performance and breakdown of energy tier
- Energy Tiers: This sample includes 80 projects across a wide range of building types, with commercial being the most common. Most ICI (86%) projects are built to the minimum energy performance tier. The Tier 2 (13%) projects included a diverse mix of building types, including public buildings, schools, and commercial/retail buildings and reported savings around 30%. The only Tier 4 project was a City of Calgary building, which reported 60.7% savings.
Industrial, Commercial and Institutional (ICI), NECB 2017: Energy performance
- Energy savings: 11 permits, the majority of them warehouses. As with the MURBs, all buildings were modelled better than the minimum energy performance requirement.
For all archetypes
Envelope improvements are doing less work than expected. Wall insulation fell below the NECB prescriptive minimum in every MURB reviewed, and roof insulation exceeded the minimum in only one building. Where MURBs did better than the reference, better-performing windows and reduced window area drove the improvement rather than opaque assemblies. Window RSI was consistently above the NECB minimum, and fenestration and door-to-wall ratio (FDWR) were consistently below the 33% maximum. The ICI NECB 2020 dataset shows the clearest trend in the study: wall, roof and window performance all improve from Tier 1 to Tier 2, and window area drops as tiers rise. Under NECB 2017, both MURB and ICI walls and roofs averaged below the prescriptive minimum.
On mechanical systems, natural gas remains the dominant heating fuel in both groups, but system selection varies from condensing and non-condensing boilers, furnaces, hybrid systems, district energy and heat pumps (including in buildings that only met Tier 1).