Background: The 307 Westlake S&C will house laboratories facilities for two biomedical research institutions in Seattle. It will contain some limited office and retail space as well. Our project is pursuing LEED Certification and planning to participate in the upcoming S&C Pilot Program. The design incorporates several energy-savings measures, and so our target credits include Energy Optimization Credit EA1. Our initial model runs used the LEED NC Rating System, using various assumptions for TI systems, and results indicated a minimum 20% savings. At that point, we decided to put the energy modeling effort on hold until we learned more about how modeling would be handled for Shell & Core projects. The project is now under construction, and we would like to complete our energy modeling effort. Since last summer, we have completed lease arrangements and have the interior layout and mechanical and electrical designs of the TI spaces. We have also had the opportunity to review the draft S&C Rating System. Based on our review of the latest S&C draft, we understand that the approach for EA1 will be to model S&C systems only. The question then becomes how to establish the boundary between S&C and the TI portion. For some S&C projects, it might be straightforward to establish the boundary between S&C and the TI portion. In our case, it is not, so we would like to propose an alternate approach for our project. In addition, we have several questions that relate to adapting the LEED guidelines to our laboratory facility and its innovative HVAC system design. Proposed Modeling Approach: We to perform and document an energy model of the entire building, not just shell and core. We believe this is a sound approach and a conservative one. We know what the interior is going to be
The LEED Core & Shell pilot program is not yet ready, but this inquiry can be addressed in the context of LEED for New Construction (LEED-NC). As the energy modeling protocol now stands in LEED-NC, energy models should be prepared with all applicable loads and equipment included in the modeling results, as you have proposed. The modeling results are then subject to post-processing as explained in the LEED V2.1 Reference Guide on pages 145 to 148. The post-processing simply factors out the non-regulated components from the modeling results. In this manner the HVAC loads associated with the non-regulated equipment are taken into account. Regarding the additional questions as they apply to LEED-NC: 1. Laboratory systems meeting 188.8.131.52 are exempt from the exhaust air energy recovery requirements in 90.1. As such heat recovery in this area would be considered a valid energy saving strategy applied to a regulated component. Follow the ECB Exceptional Calculation Methods in section 11.5. See numerous previous CIRs (EAc1.1 dated 7/22/03, 1/20/02, 7/10/01, 11/9/01, 6/27/01 (several), and 6/7/01) for guidance on applying this method. 2. The design building should be modeled with the actual HVAC equipment, which has been designed for the project. If following the ASHRAE 90.1 HVAC Systems Map (Figure 11.4.3) results in the selection of a chilled water system and the size of the system dictates two equal sized chillers (see Table 11.4.3A, Note 5), then this becomes the requirement for the budget building. Comparisons are made between the design and budget buildings. This is a valid potential energy optimization strategy. 3. Regarding plug load capacities the energy models should include a level appropriate to the building type. Specific guidance on selecting the appropriate level is contained in the LEED V2.1 Reference Guide on page 143 under the "Process energy" section. 4. Garage ventilation is indeed non-regulated as stated on page 145 of the LEED V2.1 Reference Guide. Energy saving measures applied to non-regulated components can obtain credit for savings as an innovation credit. To achieve a point for this strategy, the applicant must demonstrate that energy savings represent a significant fraction of building energy use (at least 5%); comparable to the level of achievement required by EAc1. Follow the procedures outlined in numerous, previous CIRs (EAc1.1 dated 8/15/03, IDc1.1 dated 4/17/03, 8/16/02, 6/21/02).
Related Addenda (Corrections & Interpretations)