As a result of our meeting with Tim and Danielle, we became familiar with a database that contains information about the topological characteristics of nearly 2000 soft-story-buildings, such as dimensions of constructed walls, open spaces, number of stories, etc. Our goal is to perform a statistical characterization of these buildings, in order to detect patterns that are repeated for several buildings, so that we can come up with a few of their typical characteristics. The motivation to do this is to be able to select these typical characteristics as an input to the FEMA methodology mentioned below, so as to determine the expected forces that the such a typical building can resist. With this information, we expect to be able to: (1) communicate risk better among residents and owners; and (2) to guide the prioritization process by focusing on those buildings that might be below the average conditions.
FEMA: As part of the integral retrofitting project in San Francisco, FEMA launched the FEMA 807 project. FEMA 807 created a report where they established different levels of evaluation to wooden soft-1st-story buildings. The degree of sophistication and refinement in the evaluation is directly related to the amount of details that are needed for the evaluation. Given the kind of data that we have for the typical buildings, we are going to use the most simplified analysis that FEMA 807 proposes to assess the degree of vulnerability that building have. However, we still will have to take some considerations according to the experience of the Building Inspector of Oakland and Stanford Professors that have experience in the structural engineering practice.
As far as what methodology will be used, FEMA 807 Chapter 3, will be used. We will get the demand forces on the buildings and compare those with the building strength. The ratio between these parameters could give a good idea of the level vulnerability of buildings.
With most of the community meetings being conducted last week, our team now has access to a broad range of data from community stakeholders. From community meetings, Sue Piper, point person on community engagement, gathered together a matrix of major issues (financial, technical, tenant/landlord specific) including tenant and landlord positions on concerns that applied to both. Additionally, she put together a spreadsheet of all the community’s comments organized by meeting, which will allow us to get a better feel for the needs of each distinct neighborhood represented. Finally, the survey Victoria sent out at the beginning of the year received around 300 responses. She sent us the raw data as well as some initial analysis she has performed; mostly bar graphs or pie charts that allow us to see the how people stand on an issue. This data is quantitative and does not give us insight into an individual’s reasoning for responding how they did but should help supplement the more qualitative analysis we will be able to do with feedback from community meetings.
Based on the survey data, we hope to recommend a number of options that the city can pursue. We have thus far only done a cursory analysis of the survey’s data, but have outlined a few central data points on which we will focus. These are as follows:
1) To what standards would the residents prefer their building upgraded/retrofitted? More substantial upgrades would likely be more expensive.
2) What percentage of take-home pay do residents currently spend on rent? This will determine the impact a mandatory retrofit program would have.
3) How much, in terms of a monthly rent increase, are these seismic retrofits worth to each tenant?4) Would a retrofit equal such a raise in rent that it would not be worth the increased safety?
From these initial central points, we have created three overarching questions to arrange our website presentation around. The first is what it the Acceptable Risk for each community. Acceptable risk is the level of risk that is deemed to be tolerable for these communities, as determined by a number of different social, demographic, and economic factors. Similarly, the next question to be asked is what should be the payment split between the owner and tenant when completing a retrofit? At the moment, the 70/30 tenant/owner split could be overly burdensome for many of the tenants in soft story homes. Our third question, again in line with the first two, concerns financial feasibility. If and when the soft story program becomes mandatory, which tenants or homeowners are financial incapable of affording a retrofit, and therefore would need support from the city, or a third party organization.
Dana Brechwald, a Resilience Planner with ABAG, sent us the GIS files they used to create their “Communities at Risk in Fragile Housing and Exposed to Hazards” map. Now that we have this data in addition to the City of Oakland’s data about the location of soft story apartment stock we can begin creating our own map, an overlay of the existing ABAG map with pins that designate the location of each soft-story building. This way city planners will be able to get an intuitive picture of the communities that are most at risk in the case of a natural disaster given the density of housing stock and socioeconomic fragility. Hopefully this will help policy makers better decide how to distribute the funds they have available in the most equitable way possible, and maybe even be able to see problems in specific communities that need direct addressing.