Four factors for identifying green windows and doors What does sustainability really mean? Ask ten homeowners—or builders—and you’ll get different answers from everyone. Fortunately, when it comes to identifying windows and doors for a sustainable building project, there are some well-established criteria to consider and discuss. 1. Energy efficiency Ever since the oil crisis of the 1970s, manufacturers like JELD-WEN have designed numerous innovations into their windows and doors to improve energy efficiency. This includes Low-E glass and its advanced counterparts, LoE3-366 and Low-E EC, all of which use invisible metallic coatings on the glass to reflect the sun’s heat without affecting visibility. In addition, inert, nontoxic, and invisible gas (usually argon or krypton) captured between glass panes further insulates windows to help keep heat out or in, depending on the season. The U.S. Environmental Protection Agency’s (EPA’s) ENERGY STAR program establishes common energy efficiency standards for a wide range of products. To become ENERGY…