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<br />VERSiON 1.0 1/12/95 <br /> <br />LEVEL TWO: Building DDF <br /> <br />User-Entered <br />Building DOF <br /> <br />Modified <br />Building DDF <br /> <br />BLUE Blocks (Override Default). If the Default DDF does not <br />accurately reflect the specific building under evaluation, users may <br />enter more appropriate estimates based on engineering judgement and <br />common sense. If the OTHER building type is selected, then no default <br />values are provided and the user MUST enter building-specific <br />estimates. Whenever a user enters a depth-damage estimate, the <br />program uses these values rather than the default values, although the <br />default values are displayed for comparison to the user-entered values. <br /> <br />If building damage data at one observed flood depth are available, this <br />value may be used to calibrate the user-entered building DDF. The <br />percent damage at this flood depth can be set to agree with the actual <br />damages, and damages at other flood depths can be smoothly adjusted <br />to be consistent with the observed damage data point. However, it is <br />important to note that the damages in a single flood mayor may not be <br />representative of future expected damages, depending on whether or <br />not unusual circumstances affected the observed damages. <br /> <br />Overriding the default depth-damage estimates is perfectly acceptable, <br />indeed it is required in order to get a valid benefit-cost analysis <br />whenever the default estimates do not accurately reflect the building <br />under evaluation. For example, if a building is unusually resistant or <br />unusually vulnerable to flood damage this information should be <br />reflected in the user-entered depth-damage function. <br /> <br />Also, the default depth-damage estimates consider predominantly water <br />depth. If high velocity flows, ice or debris-induced damage, erosion and <br />soiVfoundation failure, or unusually long-duration flooding are likely, <br />then default depth-damage estimates MUST be adjusted accordingly. <br /> <br /> <br />YELLOW Biocks (Results). The Modified DDF (%) takes into <br />account the demolition threshold damage percentage entered on the <br />LEVEL ONE Data page and adjusts the DDF accordingly. For <br />example, if the demolition percentage is 40% then all damages at or <br />above 40% are assumed to be 100%, because the building would be <br />expected to be demolished as a total loss at that level of damage. <br /> <br />YELLOW Blocks (Results); The depth-damage percentages of the <br />Modified DDF (%) are converted to dollars in the final column of the <br />depth-damage table. <br /> <br />8-6 <br />