The project team is inquiring what requirements have to be met for LEED BD+C: Homes 2008 MR credit 2: Environmentally Preferable Products for projects that have a combination of concrete and framing. For sections of the building that contain both concrete and wood, projects must meet credit requirements for both concrete and wood for at least 90% of the total component, even if the framing is not structural. This includes the components in Table 1. Environmentally Preferable Products; ‘exterior wall – framing/wall structure’, ‘floor - framing’, ‘interior wall - framing’, and ‘roof - framing’. If a building is primarily structural wood framed construction, but built over a single story of concrete podium construction (such as over a parking garage or commercial spaces), only the wood framing must meet credit requirements.
For the component ‘foundation: aggregate’ and ‘foundation: cement’ components, credit requirements must only be met for slab and any below grade foundation walls/structural components.
If a project would like to earn credit for using at least 30% fly ash or slag as a cement substitute, they may average this across multiple components. For example, if they use 40% fly ash for the foundation and 25% for the roof, they may get credit for installing fly ash for both ‘foundation-cement’ and ‘roof-framing’.