This paper presents the overview of the currently practiced new housing constructions in Ontario based on a survey to local homebuilders in the Greater Toronto Area (GTA), which was conducted as part of the proposed methodology to determine the suitability of the potential optimal upgrades considered for the analysis. Also presented in this paper is the economic feasibility study of the identified optimal upgrades from the survey for the selected cities in Ontario with varying climatic conditions.

Based on the results of the survey, it was concluded that the participant builders have already implemented or considered for implementation some of the advanced technologies into their current building practices to achieve the energy performance level that exceeded the minimum requirements as specified by the existing Ontario Building Code (OBC). Furthermore, the results of the economic feasibility study showed that, based on the life cycle analysis of 30 years, the combination of optimal upgrades comprised of increasing the thermal resistance of the building envelope components, and installations of the most energy-efficient heating, ventilating, and air-conditioning (HVAC) system could achieve up to 31% reduction in both the estimated total annual energy consumption and greenhouse gas (GHG) emissions in comparison to the same building configuration, but built in accordance with the OBC, and without the implementation of the identified optimal upgrades. Furthermore, with the installation of a residential photovoltaic (PV) system combined with these upgrades, the estimated total profit of up to $89,035 could be achieved through Ontario’s micro Feed-in-Tariff (FIT) program, allowing a homeowner to pay for the installation of additional upgrade(s) to further improve the energy efficiency level of a home, ultimately reaching the net zero energy status.