Safe Enough to Stay - ABAG Earthquake and Hazards Program

Safe Enough to StaySection III:What needs to be done toenable residents to shelter inplace for days and monthsafter a large earthquake?After an earthquake, we want San Franciscans to shelter in place intheir homes. Yet, while a building may be structurally safe enoughto occupy following a seismic event, it may be considered unsafe orsubstandard under the applicable codes, 36 because it won’t meetthe existing minimum standards for health and safety for residentialhousing in non-emergency times. How do we set a post-earthquakestandard that is “safe enough” yet not so stringent that people are toldunnecessarily to vacate their homes to find temporary shelter?SPUR believes it is critical to define alternative shelter-in-placehousing standards that allow people to stay in their homes safely butdon’t deem otherwise safe buildings unsuitable for occupancy. Thesealternative standards would supersede regular code requirementsduring a housing-emergency period declared by the city after a majorearthquake. Such an emergency period might extend for days, weeksor longer.Shelter-in-place alternative standards could significantly reduceemergency-shelter and interim-housing needs while maintaining thelocal population base necessary to support recovery. The alternativestandards should become more stringent as San Francisco recoversafter the earthquake and should remain in force until the city’shousing stock is completely restored.Shelter-in-place standards should be “phased,” with the expectationthat repairs need to be made over time to restore habitability. Forexample, certain standards that will be considered acceptableimmediately following the earthquake (such as using portable outdoortoilets) will not be acceptable three months after the earthquake. Theshelter-in-place standards should define which needs will be metby the building itself and which will be met outside the building foreach time phase. Those resources that must be accessible outsidethe building will have to be provided in a neighborhood service centerlocated in close proximity to shelter-in-place housing.Figure 5 illustrates the idea of alternative habitability standardsthat would apply in emergencies and gradually revert to normalcode requirements. The blue line represents the code standards forhabitability that normally apply. When an earthquake occurs, somedamage might result, but if the damage is light, it will not affect thecity’s overall resilience, so no relaxation of the normal standardswould be justified. A declared housing emergency, however, indicatesthat damage — and possibly housing loss — is significant enoughto justify special measures to speed response and recovery. Thestepped red line represents the minimum standards to be metwithin a residence. The pink shaded area represents resources thata neighborhood service center provides outside the home. The redshaded area represents the actual loss of habitable housing. Asrepairs are made, buildings (and housing standards) return to normal.One of the challenges in developing and implementing shelter inplacestandards is that these alternative standards do not correspondwith any currently adopted standards in San Francisco’s BuildingCode, Housing Code or other codes. Once San Francisco has adoptedshelter in place as a performance goal for new and/or existingbuildings, local building codes will need to be amended.Minimum habitability requirements for occupancyafter the earthquakeWhen should a building be considered acceptable for shelter in place?Conditions that are adequate right after the earthquake may not beacceptable one to three months down the road. SPUR has identifiedfive different post-earthquake time periods and defined the majorhabitability requirements for each:1. The immediate post-earthquake period2. One week after the earthquake3. One month after the earthquake4. Three months after the earthquake5. After the declared housing emergency is overIncreasingly robust habitability standards will need to be met in eachphase, as described in Figure 6 (page 28).Even if all of the alternative standards are met, however, people maychoose not to shelter in place. There is no obligation under thesealternative regulations for any person to remain in any residence; anyperson might choose to relocate to emergency or temporary shelter,move to an undamaged facility or make other arrangements.36 The minimum standards for health and safety for residential occupancy atnon-emergency times are detailed in the California Health and Safety Code andin the San Francisco Housing Code.26 SPUR Report > January 2012