HDG & LEED
Leadership in Energy and Environmental Design (LEED®) is the leading rating system for a buildings performance in the areas of economic return, environmental impact, and personal health. The hot-dip galvanizing process is not LEED® rated, because processes and products are categorized as contributing to the overall LEED® score for a building under construction or completed. LEED® v4 was approved in 2013, but specifiers can choose which program to report to (2009 or v4) through June 2015.
The main area where galvanizing contributes to LEED® 2009 is due to the recycled content. HDG can always contribute 2 points in the key area of Materials & Resources Credit 4: Recycled Content for having more than 20% of the total value of the material coming from recycled sources. Additionally, because of the extremely high recycling rate of both zinc and steel, HDG can actually earn an extra credit point under Innovations in Design Credit 1: Path 2 Exemplary Performance because the recycled content actually exceeds 30%.
Hot-dip galvanizing may (on a job-by-job basis) be able to provide additional LEED 2009 points under MR Credit 5: Regional Materials, MR Credit 3: Materials Reuse, ID Credit 1: Path 1 Innovation in Design, and ID Credit 1: Path 2 Exemplary Performance.
However, the new LEED® v4 (passed in 2013) is quite different than its previous versions. The USGBC is transitioning LEED® from a prescriptive checklist to a more definitive measure of environmental impact from start to finish. The goal is more transparency in materials, so specifiers can make the best choices. The new version has a heavy focus on Environmental Product Declarations (EPDs) which detail the materials used in a building and their economic impact (such as an LCA). There also is a heavy emphasis on the supply chain knowing not only what the final manufacturer did to the material, but where they acquire their base material, and how responsibly it is mined, etc. Finally, there is an opportunity for credit if the material you are using has a published material ingredient list, similar to what you see on food labels.
The AGA is currently working on an industry-wide EPD, and Material Ingredient lists based on the type of zinc in the kettle (high grade, prime western, etc.). The International Zinc Association (IZA) is working on more information related to zinc and supply chain.