Life Cycle Assessment of Common Materials Used for Exterior Window Shadings in Residential Buildings

The use of daylight has become an essential concern in improving environmental quality and decreasing overall energy consumption by providing natural daylight, which results in minimizing the energy use for indoor lighting, cooling and heating loads. Exterior solar shadings for windows have been widely used in hot or subtropics climates to reduce energy consumption and cut air conditioning costs in residential sector. The most common material types used in exterior solar shadings are aluminum and wood. Life cycle assessment (LCA) wasused to evaluate the environmental effects of the aforementioned materials in typical exterior shadings used in residential buildings. The study compiled a Life-Cycle Inventory (LCI) for quantifying and characterizing the energy consumption and emissions to the environment of these common materials during the life cycle of solar shadings. A life cycle methodology that follows the International Organization for Standardization (ISO) 14040 standard for life cycle assessment was used in this study. Based on the analysis conducted, the positive and negative effects of aluminum and wood shadings on environment for different types of shadings are presented. It was concluded that wood shadings are more environmentally-friendly than aluminum shadings during their life cycles and are better alternatives to be used by building professionals to achieve a more sustainable design.