Comprehensive Energy and Decarbonisation Audit of a Multi-Unit Residential Building in Toronto: Methods, Findings, and Recommendations

Abstract

This research investigates a structured energy audit methodology to support the decarbonisation of multi-residential buildings, with a primary focus on operational energy performance. The objective is to develop and apply a systematic framework that integrates audit levels, detailed data collection, and software-based energy modelling to quantify energy use and greenhouse gas emissions. The methodology combines site inspections, thermographic analysis, benchmarking, and eQuest simulation to evaluate baseline conditions and retrofit scenarios. Results identify space heating and electricity consumption as dominant energy and emissions drivers. Targeted retrofit measures demonstrate substantial potential to reduce energy demand and carbon intensity when expressed in kg CO₂e. Importantly, the correlation analysis does not capture retrofit interactions, system efficiencies, or behavioural adaptations following upgrades, nor the compounding effects of bundled measures. Carbon-counting results show these combined effects to be significant, with the full retrofit package achieving an overall emissions reduction of approximately 25%, equivalent to more than 1,100 t CO₂e annually. Overall, separating results from interpretation strengthens decision-making and confirms the value of operationally focused audits for prioritising decarbonisation strategies in existing multi-residential building stock.