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4.3 Building Data The total building area of 162,385 square feet consists of 74,777 square feet on the upper (office) level and 87,608 square feet on the lower (parking and fire station level). Building replacement value of $27,774,330 was estimated from the 1995 engineering estimate made by Dames & Moore as part of an earlier seismic vulnerability study, adjusted to 2004 values using FEMA's Inflation Adjuster. Using the Inflation Adjuster, with recent federal data on inflation rates for the past several years, yields an adjustment factor between 1995 and 2004 of 1.227. The building demolition damage percentage was estimated to be 40% of building replacement value. The default FEMA value is 50%. However, the FEMA guidance in the User's Manual (FEMA, October 25, 1995) for the Full Data Module for Benefit-Cost Analysis of Seismic Hazard Mitigation Projects notes that: "For older, somewhat substandard buildings, the demolition threshold may be quite Iow (e.g., 20% to 30%). Earlier studies of the building (Dames and Moore, 1995) assumed a 25% demolition percentage. Therefore, using a 40% threshold is conservative and fully consistent with FEMA guidance. The building is 40-years old and has significant functional deficiencies ---- as well as substantial seismic deficiencies. Therefore, using a demolition ' percentage less than 50% appears fully justified. 4.4 Building Seismic Damage Functions The vulnerability of the existing building to seismic damage is expressed mathematically by fragility curves. Fragility curves incorporate the engineering analyses of the building and express the vulnerability as the probability that a building will be in each of several defined damage states at any level of ground shaking. Fragility curves include "A" values (acceleration as a fraction of g) which are the level of shaking at which there is 50% chance of the building being in the defined damage state or higher. Fragility curves also include "beta" values which are Iognormal dispersion (standard deviation) parameters reflecting the uncertainty and randomness. Fragility curves in Chapter 5 of the Technical Appendix (Table 5-3) were input into the FEMA Fragility Curve Calculator to calculate seismic damage functions (percent damage for various bins of PGA) in the format used in the FEMA Full Data Module for Benefit-Cost Analysis of Seismic Hazard Mitigation Projects. 8