The objective of this study is to assess the impact of energy efficiency upgrade scenarios on the greenhouse gas (GHG) emissions from the Canadian housing stock. The study is targeted towards policy makers who can use the results of this techno-economic study to pass appropriate legislation to curtail GHG emissions from the Canadian housing stock.The analysis was conducted using the Canadian Residential End-use Energy Model (CREEM). CREEM is representative of the Canadian housing stock, and is capable of assessing the GHG and energy impact of retrofits.Cost estimates were updated to assess the economic feasibility of the upgrade by calculating the indicator "GHG emissions reduction per dollar investment" (GHGRPDI) calculated by dividing the reduction in annual GHG emissions by the investment cost.Retrofits were ranked for each house in CREEM, based on the indicator GHGRPDI. The analysis is for houses that are eligible for a certain upgrade. The top five retrofits were determined for each province, and are presented as part of this study. For example, the top 5 retrofits (in order) that are suited for Ontario based on the GHGRPDI are: 1. Upgrade the lighting system to high efficient compact fluorescent lights. 2. Install programmable thermostats in all eligible houses. 3. Ceiling insulation upgrade to RSI 7.04 for all eligible houses. 4. Install low flow shower heads and aerators for all eligible houses. 5. Basement ceiling insulation of at least RSI 5.5 in all eligible houses.