In Canada, energy consumption and greenhouse gas emissions remain key issues. This study aims to investigate energy efficiency and potential trends using energy monitoring of a newly built Mult-Unit Residential Building (MURB) utilizing a fuel-switching space heating system. To achieve this, energy consumption data was collected over three years for multiple residential units within the MURB in Edmonton, Alberta, which is characterized by a cold climate. The fuel-switching, hybrid space heating system consists of an electrically powered air-source heat pump (ASHP) and a natural gas tankless water heater (TWH). This study presents the key findings and lessons learned from the in-situ evaluation. It was found that the case study units exhibit high energy performance when benchmarked against provincial and Canadian averages. There were also variations within the units for different utilizations of the fuel-switching system that on average showed higher TWH usage.