Appeal for Ruling on LEED CS CIR for credit EAc1 dated 2/11/08 CIR: The PERCENT energy cost savings for EAc1 is based solely on Core & Shell components. Reviewer response: The request "significantly modified the approved calculation methodology." "The methodology published in the LEED-CS v2.0 Reference Guide was balloted and approved by the USGBC members and cannot be modified via a CIR." Appeal: A. The CIR proposes to clarify, not modify, a calculation method. B. The Reference Guide supports the proposed interpretation of the calculation method C. This interpretation is consistent with the other LEED CS credits. A. LEED-CS RATING SYSTEM, APPENDIX 2 IS UNCLEAR ON THE CALCULATION PROCEDURE FOR EAc1. THE RATING SYSTEM INTENT SUGGESTS THE USE OF ONLY CORE & SHELL ENERGY. ITEM 1.1: Projects must use ASHRAE 90.1-2004 Building Performance Rating Method. This requires that all loads, including tenant loads, be modeled. It does not indicate whether tenant energy is included in the percentage calculations. ITEM 1.2: Tenant spaces are defined by energy using components paid for, metered and apportioned, or billed to, the tenant. ITEM 1.3: "Thus, the scope of a LEED CS project is limited to those aspects of the project over which the developer has direct control." ITEM 5: The energy cost of the Budget and Design buildings determine the percentage savings. We contend that Items 1.2 and 1.3 should decide whether the annual costs are of the ENTIRE building or of CORE & SHELL. B. LEED-CS REFERENCE GUIDE, APPENDIX "CORE & SHELL ENERGY MODELING GUIDELINES" CLEARLY DIFFERENTIATES BETWEEN CORE & SHELL VS. TENANT ENERGY USE. IMPLICATION: UTILIZE CORE & SHELL ENERGY USE FOR THE EAc1 PERCENTAGE CALCULATION. The percent energy cost savings is calculated as follows: a. MODEL THE ENTIRE BUILDING, including Core & Shell areas AND Tenant Fitout areas NOTE: This procedure is not disputed. b. TRACK SEPARATELY the energy use of Core & Shell vs. Tenant Fitout. NOTE: See 2.2.1.1 and 3.2.1.1. "Model SEPARATE electric meters for the lighting in the core." See 2.2.2.1 and 3.2.2.1 "Model SEPARATE meters for tenant plug loads and process loads." This signals the intent to use ONLY Core & Shell costs for the percentage calculation. c. SIMULATE, THEN CALCULATE the percentage energy cost savings, using Steps 4 and 5. NOTE: Step 5.1 references the "budget building" and the "design building." It does not say whether these models are just for CORE & SHELL or the ENTIRE building. However, under "2. Proposed Building Model" (term used interchangeably with "Design Building") the proposed building is listed as "2.1 Core & Shell Building." Same for "2. Baseline Building Model." When Step 5.1 refers to the "annual costs of the budget building and design building," it is consistent to assume that, per Step 2, "building" means "Core & Shell building." Finally, Step 5.3 does not indicate whether the calculation is done using only Core & Shell energy cost, as we believe is the intent of the document, or using the energy cost of the entire building. We contend that this was an editorial oversight. C. ONLY THE PROPOSED APPROACH IS CONSISTENT WITH THE OTHER LEED CS CREDITS Tenant fit-out is not included in the calculation of percentages for: EAc6 Green Power WEc3 Water Use Reduction MRc2, Construction Waste Management MRc3, Materials Reuse MRc4 Recycled Content MRc5, Regional Materials MRc6, Certified Wood EQc4.1-4.4, Low-Emitting Materials EAC2 Renewable Energy references the energy use of the entire building. The percentage savings for CS is 1% vs. 2.5% for NC. For EAc1 the percentages of CS and NC are identical, indicating that the CS calculation refers to Core & Shell energy only.
The applicant is requesting clarification in calculating percentage improvement for EAc1. Based upon the justification provided in the appeal and the proposed approach in the original CIR, the calculation methodology as understood by the design team is not acceptable and does not meet the requirements of EAC1 or Appendix G of ASHRAE 90.1-2004 which requires that the proposed building performance and baseline building performance to include all end-use load components. No doubt, LEED-CS addresses energy optimization of the core and shell systems but at the same time also provides an opportunity for the developer/owner to incorporate energy efficiency features to be included in the sales/lease agreement for fit out of tenant spaces to optimize total operational building energy use. This opportunity may or may not be available to all the owners or may not be feasible at all in some developments. Therefore, it is essential to establish a minimum benchmark for energy optimization, keeping in mind that projects in different markets with different project teams are approaching the energy modeling requirements in a similar manner. Hence, the energy cost of the tenant spaces in those projects on which the developer/owner has no control is essentially kept energy neutral. Therefore, the lighting and plug loads including any HVAC system not part of the core and shell scope should be kept similar in both the proposed and baseline building as prescribed by the relevant section of ASHRAE Standard 90.1-2004 and thus the resultant energy use of the tenant spaces must not be subtracted from the calculations when calculating percentage improvement for EAc1. To further clarify, in EAc1 calculations, the proposed building performance and the baseline performance refer to the total annual energy cost of the whole project which includes the core and shell and tenant scope of work. For projects that can demonstrate energy optimization of the tenant spaces through tenant sales/ lease agreement requirements as part of the tenant scope of work can take credit for the energy cost of the tenant spaces. This approach is acceptable based on published erratum for LEED-CS v2.0 on the USGBC website (http://www.usgbc.org/ShowFile.aspx?DocumentID=3334). Applicable Internationally.