One of the most obvious differences to concrete producers in version 4 of the LEED rating system (LEED v4) may not be the addition of new credit categories, but the lack of credits with which producers are familiar. In past versions, credits related to regional materials and recycled content were understood by producers, and in many cases became typical business practice. These material characteristics now contribute to one credit category, Sourcing of Raw Materials, which is the focus of this article.
MRc3: Building product disclosure and optimization—sourcing of raw materials:
The intent of the credit reads: “To encourage the use of products and materials for which life-cycle information is available and that have environmentally, economically, and socially preferable life-cycle impacts. To reward project teams for selecting products verified to have been extracted or sourced in a responsible manner.” There are two options for this credit: raw material source and extraction reporting and leadership extraction practices.
The raw material source and extraction reporting option requires using 20 permanently installed products, sourced from at least five different manufacturers, that have a publicly released report from suppliers including:
- Raw material supplier extraction locations,
- A commitment to long-term ecologically responsible land use,
- A commitment to reducing environmental harms from extraction and/or manufacturing processes, and,
- A commitment to meeting applicable standards or programs voluntarily that address responsible sourcing criteria.
If a manufacturer provides a self-declared report, products are valued at one-half of a product. Manufacturers that have third-party verified corporate sustainability reports (CSR), conforming to one of the frameworks listed in the table, are valued at one whole product.
For option 2, leadership extraction practices, 25% of the total value of permanently installed building products must meet at least one of the following criteria:
- Bio-based according to the Sustainable Agriculture Network’s Sustainable Agriculture Standard.
- New wood certified by FSC or USGBC-approved equivalent.
- Reused materials.
- Recycled content, which is still calculated as post-consumer content plus ½ pre-consumer content.
- USGBC-approved program.
For the purpose of calculations, products are valued based on source location:
- Products sourced within 100 miles of project site are valued at 200% of their cost.
- Products sourced domestically within 500 miles of project site are valued at 150% of their cost.
In option 2, previous materials credits related to recycled content and regional materials are essentially combined.
With the U.S. Green Building Council’s release of LEED v4, the organization continues to push the envelope toward more sustainable building. Like with previous versions of LEED, the supplementary cementitious materials used in concrete, such as fly ash, silica fume, and slag cement, are considered post-industrial recycled content. And concrete and its constituents are typically sourced very close to the project site and can add to the material valuation of this credit. But producers must now meet both of these criteria to maximize its contribution to a more-sustainable project.