Window Performance Grade Calculator

Selecting the right windows for your construction project is a crucial decision that directly impacts a building’s energy efficiency, comfort, and compliance with building codes. In Canada, adhering to the Canadian National Building Code and various provincial, territorial, and municipal building codes is essential. To simplify this process and aid fenestration product manufacturers, as well as their stakeholders, Energi has introduced the Window Performance Grade Calculator.

The Significance of Window Performance Grades

Residential complex

Window performance grades play a pivotal role in ensuring that the windows installed in a building meet the required standards for energy efficiency and thermal performance. These grades are influenced by various factors, including geographic location, terrain conditions, building height, and shape. To meet the stringent demands of Canadian building codes, it is imperative to calculate the appropriate performance grade that corresponds to the specific project.

Energi’s Window Performance Grade Calculator

Energi, a trusted name in the field of energy efficiency and building code compliance, has developed a user-friendly Window Performance Grade Calculator. This tool is designed to assist architects, builders, manufacturers, and all those involved in the construction process in selecting windows that align with the applicable building codes.

Key Features of the Calculator

  1. Geographic Location: The calculator takes into account the geographic location of the construction project. With data from over 640 selected Canadian locations, including climate design data from the 2010 National Building Code, it ensures that the window’s performance grade is tailored to the local climate conditions.
  2. Terrain Conditions: Different terrains can impact a building’s energy needs. Whether your project is situated in an urban area or a more rural setting, the calculator considers these terrain conditions in determining the required performance grade.
  3. Building Height & Shape: The height and shape of a building affect its energy consumption and thermal performance. Energi’s calculator incorporates these factors into the calculation, ensuring that the chosen windows meet the unique requirements of the structure.

Simplifying Compliance

Patio Windows and Doors

The Window Performance Grade Calculator from Energi simplifies the often complex task of selecting windows that meet the stringent requirements of the Canadian building codes. It provides a clear and systematic way to determine the appropriate performance grade for your project, ensuring that you are in compliance with the law and that your building operates efficiently.

By using this tool, you not only save time and effort but also gain the peace of mind that comes with knowing that your windows are contributing to a more sustainable and energy-efficient built environment.


In the world of construction, every detail matters. Energi’s Window Performance Grade Calculator is a valuable resource for those seeking to make informed decisions about their windows, ensuring that their projects align with the Canadian National Building Code and other relevant building codes. It’s a testament to Energi’s commitment to advancing energy efficiency and building code compliance in the construction industry.