Disaster Highlights 2007 0709 v2

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Why inventory soft-story buildings? What does an invento count? Some local governments in the Bay Area have conducted inventories of soft- story structures in their communities. However, these inventories were created using different methodologies to supply different types of information for emergency response and the design of mitigation programs. Thus, the number of units can't be added together for a regional inventory. ~ The Emergency Preparedness Council of Santa Clara County and its cities hired the Collaborative for Disaster Mitigation at San Jose State to count the number of these buildings and map them so that fire departments would know where to conduct search and rescue operations after an earthquake. Their inventory defines a multifamily building as one containing 4 or more units. They identified 2,630 building containing 33,119 units. ~ The City of Berkeley inventory includes buildings both with units on the first floor and with only parking. Their inventory was conducted due to the City's concern about potentially high shelter populations after quakes and the preservation of its housing stock. The inventory defines a multifamily building as one containing 5 or more units. The City identified approximately 400 buildings containing about 5,000 units. Other users require more consistent and reliable information: ~ State and federal government agencies are concerned about counting the number of such buildings and the residential units in them to estimate potential dollar losses in future earthquakes. ~ ABAG uses estimates of the number of these units to estimate the number of uninhabitable housing units, which, in turn, are used to generate the number of people who will require emergency shelter so that the American Red Cross and others can plan for such services. An inventory is also part of a disclosure program. ABAG held a policy forum, or "charrette," to brainstorm ideas on how to increase the pace of soft-story retrofitting. The consensus was that mandatory disclosure of the hazard to current and future tenants, together with non-technical explanations, or warnings, of the hazard, could be helpful. For such uses, the inventory needs to be more consistent than one intended to estimate losses. Before additional local governments in the Bay Area conduct inventories, a consensus format of the inventories is needed based on the following: ~ Clearly define what is meant by "soft-story" throughout the Bay Area using, as a start, the definition in the International Existing Building Code Appendix Chapter A4 (IEBC-A4) as "wood-frame buildings with soft, weak or open-front walls." Thus, soft-story buildings can include those with wood-frame walls and parking on all or part of the first floor. Soft- story buildings due to large open commercial space on the first floor are more difficult to identify in an inventory. ~ Define multifamily residential buildings for purposes of this inventory based on IEBC-A4 as apartments or condos with 3 or more units per building. (IEBC-A4 also currently includes hotels with 6 or more units, lodging houses, and congregate residences.) ~ Be conservative in conducting the initial drive-by inventory. ~ Allow owners to contest the designation of their building as having a soft-story using the technical definitions in the IEBC-A4. ~ Identify procedures for change in status based on compliance with the IEBC-A4 retrofittin standards. November 14, 2005 Multi-Jurisdictional Local Hazard Mitigation Plan (LHMP) Policy Number HSNG-c-4 Both the Santa Clara County inventory and the City of Berkeley inventory cover buildings with "tuck under" parking so there are housing units on the first floor, as well as buildings with only parking on the first floor. R,_,\.f 3nl St,m" ~IlJ hi Tuck-Under Parking Roof_ Building with Parking on Entire First Floor LHMP Policy Number HSNG-c-5 HSNG-c-6