The U.S. Green Building Council Leadership in Energy & Environmental Design (LEED) Green Building Rating System aims to improve occupant well-being, environmental performance and economic returns of buildings using established and innovative practices, standards and technologies.
Steel construction materials, including hollow metal doors and frames, typically generate credits in green building certification programs and reduce the building's carbon footprint.
Materials & Resources Credit 4: Recycled Content intends to increase demand for building products that incorporate recycled content materials, thereby reducing impacts resulting from extraction and processing of virgin materials. Steel building products contribute positively toward points under Credits 4.1 and 4.2:
Credit 4.1 (1 point) "Use materials with recycled content such that the sum of post-consumer recycled content plus one-half of the pre-consumer content constitutes at least 10% (based on cost) of the total value of the materials in the project."
Credit 4.2 (1 point) "Use materials with recycled content such that the sum of post-consumer recycled content plus one-half of the pre-consumer content constitutes at least 20% of the total value of the materials in the project.