We submitted the following narrative as part of an ID credit in the design application for our project. The USGBC reviewer commented that ". the complexities of the assumptions made for this difficult calculation are beyond the scope of this review to evaluate. This [.] should be addressed by the CIR process to evaluate [.] credit achievement." We request a technical review of the submitted credit to confirm or deny whether the project can be awarded this credit. Reduced Embodied Energy - Reduction in Material for Interior Finishes Intent: To reduce the total energy use of a building\'s lifetime by reducing the initial and recurring embodied energy through the reduction of materials used in interior finishes. Requirements: Total initial and recurring embodied energy associated with interior finishes should be reduced by 40%. The requirement can be met through reduction in use of interior finishes compared to conventional practices and/or use of lower embodied energy products for interior finishes. This project reduces the relative proportion of interior finishes (compared to a more conventional design) to reduce material usage. This produces initial embodied energy savings and energy savings associated with recurring refurbishment and maintenance activities. The project applies finishes to 72% of floors, 74% of walls, and 29% of columns compared to a conventional Czech Republic building, which is 100% finished. Ceilings of the project (excluding glass areas) are 100% finished. Analysis of energy savings related to reduction of interior finishes is based on life cycle assessment (LCA) studies of embodied energy use in office buildings. For the purposes of this analysis, energy use consists of initial embodied energy (energy to create the building), recurring embodied energy (energy to maintain the building over its lifetime), operating energy (energy to operate the building) and demolition energy (energy to demolish the building upon end of lifetime) (as proposed by Cole and Kernan, 1996). Initial embodied energy applies the initial embodied energy coefficient to finished areas. It compares the design to the baseline case, which assumes 100% finished interior surfaces. The baseline case represents typical construction practices for Czech Republic office buildings, while the design case utilises the project\'s finished areas. Initial Embodied Energy Coefficient: Carpet (floors) 0.273 GJ/m2 Plaster (columns) 0.0114 GJ/m2 Metal stud (24" OC) gypsum board & latex paint (walls/ceiling) 0.341 GJ/m2 Source: University of Bath, 2006 and Athena Institute EcoCalculator, 2007. Total recurring embodied energy (for a 60-yr service life) is calculated based on the relative significance of recurring embodied energy compared to initial embodied energy in the life cycle of energy uses. The baseline and design cases are calculated by applying the initial embodied energy coefficient to the finished areas described in the total initial embodied energy, and subsequently recurring embodied energy, as follows: Associated Initial Embodied Energy: Baseline - 67,937 GJ Design - 33,820 GJ Associated Recurring Embodied Energy: Baseline - 90,356 GJ Design - 44,981 GJ Total Embodied Energy of Applied Finishes: Baseline - 158,203 GJ Design - 78,801 GJ The project shows 50.2% savings on total embodied energy related to finishes against the baseline. Typically, initial embodied energy of materials for interior finishes makes up ~13% of the total initial embodied energy of concrete office buildings. Thus, the reduction of materials for finishes represents 6.5% (50.2% x 13%) savings on initial embodied energy. Recurring embodied energy of materials for interior finishes represents ~30% of total recurring embodied energy across the 60-yr lifetime. Thus, the reduction of materials for finishes represents 15.1% (50.2% x 30%) savings on total recurring embodied energy in the project. Total savings across total life cycle including operational energy: Total Initial Embodied Energy Savings 6.5% x 17% = 1.1% Total Recurring Embodied Energy Savings 15.1% x 23% = 3.4% Total Saving Across Whole Life Cycle 4.5% The approach indicates that significant savings can be achieved by reducing the quantity of materials for interior finishes. The approach is logical and replicable for other buildings.
The applicant is requesting the approval of an innovation credit based on the use of interior finishes with lower embodied energy, as compared to a conventional baseline. Although the project team has demonstrated that they have used materials with lower embodied energy than the baseline, it is not clear that embodied energy is a good indicator of total environmental impact. Embodied Energy is a single attribute describing how much energy is required to make a unit of material. While energy consumption typically has an associated environmental impact, the reduction of embodied energy alone does not identify or equally quantify the downstream environmental impacts, such as carbon dioxide emissions, air pollution, water eutrophication, etc. In a comparison of two materials in which one product uses more energy than the other, it does not automatically mean that the product with lower embodied energy is more environmentally friendly than the other. There are other factors that must be considered, such as the type of power that was used in the production of the material, e.g. green power compared to coal fired or nuclear generation. Please see CIR rulings dated 2/25/2003 and 1/13/2003 for more information and guidance. Applicable Internationally.