What is ENERGY STAR? It is the certification system that is used in the identification of energy-efficient products. This certification system is suitable for doors and windows among other products. The ENERGY STAR symbol is placed on a product to confirm that it meets or exceeds certain standards. The symbol is placed after the product is tested by a credible independent laboratory.
Comparing products without a single set of standards can be a daunting task. ENERGY STAR makes such comparison quite easy. However, these standards may change so as to keep up with the ever changing environmental policies and evolving technology. When comparing products, always ensure that you refer to the most recent figures. It’s worth noting that ENERGY STAR products offer different levels of energy efficiency. Take a look at these individual performance markers to understand the differences.
2022 ENERGY STAR® Standards
Windows are eligible for ENERGY STAR® based on their U-factor that measures their overall heat loss, or, their Energy Rating (ER) that combines their passive solar heat gain (SHGC) through the glass with their overall heat loss and air leakage. Models must have a U-factor of 1.22 W/m2 or lower, or, an ER of 34 or higher.
Caution is advised when selecting windows and sliding glass doors with passive solar heat gain (SHGC) values above 0.45 that will face south or west, especially if there is more glass area than exterior wall area (high window to wall ratio), as this could cause uncomfortably warm room temperatures and higher cooling costs.