Direct Answer
Structural steel is the most recycled material in the world — over 90% of structural steel in North America is recycled at end of life. Steel produced in electric arc furnace (EAF) mills — which dominate US structural steel production — has an average recycled content of 93% by weight. This makes structural steel among the most sustainable structural materials available.
Full Explanation
Steel sustainability profile: (1) Recycled content — EAF mills melt scrap steel; essentially all US W-shapes, HSS, and plate are produced with 90%+ recycled content. (2) Recyclability — at end of building life, 98%+ of structural steel is recovered and recycled (compared to concrete demolition waste, which is typically landfilled or downcycled). (3) Carbon footprint — steel production is energy-intensive, but the high recycled content and end-of-life recyclability compare favorably to concrete on a lifecycle basis. LEED v4 and other green building rating systems award points for recycled content and for structural steel's recyclability.
What This Means for Your Shop
When GCs or owners request LEED documentation for steel, you need: (1) Recycled content certification from your service center or mill — typically provided as a percentage by weight. (2) Regional material documentation if the LEED credit requires material sourcing within 500 miles. Maintain these documents for projects seeking green building certification.
Common Mistakes
Confusing 'recycled content' with 'post-consumer recycled content.' LEED defines post-consumer recycled content differently from post-industrial. Steel scrap is typically post-consumer, giving it full LEED recycled content credit.
Recommended Process
When a project is pursuing LEED or other green certification, request recycled content certifications from your service center at material ordering. Include these in your project close-out documentation package.