ENERGY STAR Series aluminum awning windows are energy efficient windows designed to reduce energy consumption and lower heating and cooling costs in a home or building. These windows are certified under the ENERGY STAR program, a joint initiative of the U.S. Environmental Protection Agency (EPA) and the U.S. Department of Energy (DOE). An aluminum awning window is a type of window that has a top hinged sash that opens from the bottom outward. They are popular in areas that experience frequent rain or snow because they keep the elements out while providing ventilation. ENERGY STAR-certified awning windows incorporate energy-saving features such as low-E (low-E) glass, insulated frames, and weatherstripping. Low-E glass helps reduce heat entering or escaping from the home, while insulated frames and weatherstripping help prevent air leaks. Overall, Energy Star Series aluminum awning windows are an excellent choice for homeowners or builders looking for energy efficient windows to help reduce energy costs and improve comfort in their home or building.