To achieve MRc4.1, the LEED professional must 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 materials in the project. To achieve MRc4.2, the sum of post-consumer recycled content plus one-half of the pre-consumer content must constitute at least 20% of total materials costs.
Thus, if project contractors purchase $10,000 worth of a wood flooring product with pre-consumer recycled content, and the total value of project materials is $1 million, then project managers can add ½ of the value of that product ($5000) to other recycled-content materials, and the total must equal or exceed $100,000 to gain a point under MRc4.1. To gain the two points offered by MRc4.2 in this example, the total value of recycled-content materials (with pre-consumer recycled-content materials counted at 50% value and post-consumer at full value) must be $200,000.
To achieve MRc6, the LEED professional must use rapidly renewable building materials and products (made from plants that are typically harvested within a ten-year cycle or shorter) for 2.5% of the total value of all building materials and products used in the project, based on cost.
Thus, if project contractors purchase $25,000 worth of a flooring product made from rapidly-renewable materials, and the total value of project materials is $1 million, then project managers have achieved this credit.
To achieve MRc7, the LEED professional must use a minimum of 50% of wood-based materials and products, which are certified in accordance with the Forest Stewardship Council’s (FSC) Principles and Criteria, for wood building components. These components include, but are not limited to, structural framing and general dimensional framing, flooring, sub-flooring, wood doors, and finishes.
Thus, if project contractors purchase $10,000 worth of a wood flooring product that is FSC-certified, and the total value of wood building components is $100,000, then project managers will need to source another $40,000 of FSC-certified wood products to achieve MRc7.
To achieve EQc4.4, “[c]omposite wood and agrifiber products used on the interior of the building (defined as inside of the weatherproofing system) shall contain no added urea-formaldehyde resins…” Under EQc4.4, composite wood and agrifiber products are defined as particleboard, medium density fiberboard (MDF), plywood, wheatboard, strawboard, panel substrates and door cores. Engineered wood flooring is also considered a composite wood product.
EcoTimber’s engineered flooring products whose wood layers are laminated together using EPI adhesives qualify for this credit. EPI glues are a newly developed two-part glue system that contains no added urea formaldehyde. It is more expensive and difficult to work with at the factory level, but is especially well suited for bonding thicker sawn wear layers to substrates when making.
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