Peel Passive House Consulting Ltd (PeelPHC) provides consulting services to developers, building owners and design professionals to help them achieve Passive House requirements for both new and existing buildings. Such projects result in substantial carbon savings, which represents one of the main goals of many organizations across Canada. The City of Toronto's Greenhouse gas (GHG) emissions reduction targets demand substantial action on existing homes. A report published in June 2021 notes that natural gas consumption in Toronto's residential buildings represents 97% of their emissions (City of Toronto, June 2021). A key finding from the net zero technical modelling included in the TransformTO Net Zero Strategy is that fossil fuels, primarily natural gas used in homes and buildings, need to be completely phased out by 2040 (City of Toronto, November 2021). For existing homes, this involves a significant improvement of energy efficiency. However, the vast majority of the industry has no experience with deep energy retrofits (for example, targeting 80-90% reduction of energy consumption and associated emissions). Additionally, homeowners are generally either not aware of or believe they cannot afford the necessary measures. Without a verified example project in Toronto to point to, PeelPHC is challenged to convince prospective single-family homeowner clients to adopt Passive House for their retrofits. Therefore, many retrofits are being undertaken with limited GHG reduction improvements. Developing technical solutions for such a retrofit is beyond the budget of typical homeowners. This grant will provide much-needed financial support to develop standardized cost-effective solutions to Passive House retrofits of single-family homes.