Item A: City Hall Complex Priority Issue

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Eugene City Hall Master Planning Utility and Maintenance Costs June 29, 2006 Page 3 Background Research and Documentation Energy Costs. Current annual energy costs have been collected and analyzed for the existing City Hall complex, Eugene Public Library, and the Public Works office at 858 Pearl. These are summarized below (Table 3) in the form of energy cost index in $/SF. These costs, in combination with an extensive database and experience base of energy costs associated with similar new pro- jects throughout the Pacific Northwest, are used to develop expected energy cost targets. Projec- tions of energy costs associated with the six primary options have been developed based on three “construction cases”, as summarized in Tables 4 and 5. Table 3. Summary of Existing Building Energy Costs. Energy Cost Facility Index, $/SF Source Eugene City Hall $2.32 Last 2 years of utility bills (steam and electricity) 858 Pearl (PW) $0.89 Last year of utility bills (steam and electricity) Eugene Public Library $0.94 Last 3 years of utility bills (gas and electricity) Review of the primary options resulted in the establishment of three construction cases where energy costs could logically be considered to differ. All cases are assumed to strive for maximum energy and water efficiency. Differences between the cases are summarized briefly in the list below. ? New construction with maximum design flexibility: New construction located on larger sites (such as the full block site) was considered to have the highest degree of flexibility in design, orientation, massing, and other considerations that are key to achieving the lowest practical energy use within a new high performance building. ? New construction with some limitations on design flexibility: In general, new construction is anticipated to create the possibility of maximum practical energy efficiency in design. Some new construction options are located on smaller sites (1/2 block) where building orientation, massing, height, footprint dimensions, and other basic parameters will have to respond to the site in ways that may restrict design options to a degree. For these cases, it is logical to assume that the maximum energy and water efficiency performance may be compromised somewhat, relative to new construction on larger, more flexible sites. ? Major renovation: Major renovation of existing buildings is expected to present the greatest set of limitations to flexibility in design of high performance buildings. Design considerations such as building orientation, footprint, floor-to-floor height, as well as other parameters will be more or less fixed by the existing conditions. While it is expected that such renovation will result in a significant reduction to the existing City Hall energy cost index, this case is anticipated to rep- resent the highest energy cost index case. Table 4 summarizes the energy cost indices that are assigned to each of the construction cases. Table 4. Energy Cost Targets for Three Construction Cases. Construction Case Energy Cost Notes Index, $/SF New construction, maximum flexibility in $0.67 Assume at 60% energy of public works/library inflated design and siting by 5%. New construction, with some limits to design $0.71 Assume midway between new unlimited and major and flexibility renovation (closer to unlimited than major renovation) Major renovation of existing City Hall $1.11 Assume similar to public works/library inflated by 5%