The Office of Energy Efficiency at Natural Resources Canada developed the EnerGuide Rating System (ERS) for use across the country. EnerGuide offers a standardized tool for evaluation that homeowners can use to assess the energy efficiency of their homes as compared to other homes of similar size and in comparable regions. Each rating, prepared by an independent rating expert, is based on an estimate of the home's annual energy use. The estimate is determined by evaluating attributes that include location, size, equipment and systems, insulation, and tests for air tightness.
In order to compare a wide range of homes across the country, the rating system uses a standard baseline of operations, occupancy and lifestyle in order to level the playing field when calculating each home's final rating and for comparing the energy efficiency of one house to another. These conditions include: a complete air change approximately every three hours; four occupants; a fixed thermostat setting of 21°C on main floors and 19°C in the basement; average hot water consumption of 225 litres per day; average national electricity consumption of 24 kWh per day; and regional weather data that is averaged over the last 30 years.
EnerGuide uses a rating scale from zero to 100. A very low score indicates a home with no insulation, major air leakage and exceptionally high energy consumption. Conversely, a score of 85 and higher indicates the opposite: a home that is well insulated, extremely air tight and well ventilated, and has no need for purchased energy on an annual basis. For new homes built to building code standards, a typical EnerGuide rating would be in the range of 65 to 72. A rating of 80 or higher is considered excellent. At lower scores of around 50 to 70, some basic sustainable house design strategies can easily bring up a home’s score to a reasonable level, however at higher ratings each extra point is more of a challenge – and an accomplishment – to achieve.
Almost all of Solares' completed projects are rated with the EnerGuide system by the Blue Green Consulting Group in Toronto.
For more information about the EnerGuide system visit the following websites: