There is a need to address the energy consumption of existing single family homes in the City of Toronto. This study outlines a process for developing and analyzing retrofit strategies for specific housing archetypes. The process was applied to Century, Century-Semi, and War Time Home archetypes. Housing data was collected and baseline energy models were prepared utilizing EnergyPlus software. Retrofit strategies were selected and analyzed for hygrothermal performance and cost. The process utilized a Brute Force method for retrofit selection considering the cost/benefit of each strategy and showed where in the process it was beneficial to upgrade each parameter. Furnace and air sealing parameters were typically upgraded early in the process as they showed an attractive cost/benefit. Basement walls and slab parameters were then upgraded, followed by exterior walls and roofs. Windows tended to be upgraded late in the process as they exhibited high capital costs compared to energy savings.